I should have added, if you try a camshaft sensor first, stay away from aftermarket sensors... They are known to cause problems in this application.

Thanks.

That other key is a dummy key... it *shouldn't* start the truck. If it does, it means your immobilizer is already defeated. This is very unusual however, it is probably just a door key.

WIth regard to the coils, I would have to get back to you this evening with test procedure, as I am actually off work right now (posting with my phone).
The easiest way if you suspect a coil issue though is to simply move the coil that works to another location. If it stops working and the other one put in the working location starts working, then the coils are not suspect.

Given that this all started after a pressure wash, I would be more concerned with the cam sensor, crank sensor, and coil conditions than I would be with the PCM at this point.

Thanks for your patience. Again I apologize for the delays today.

Can you elaborate on the crank blade coming loose? How and when did this occur, in relation to your problem?

For your coils, your secondary resistance (meter leads attached to the two spark plug terminals) should be 8.5k-11.5k ohms.

Your primary coil check is a bit more difficult though. Looking at the electrical connector with the locking tab on top, the pins are numbered 1-2-3 left to right. At rest there should be NO continuity between 1 and 2. With 1.5V applied across pins 2 and 3 (you MUST use 1.5V, and for no longer than 5-10 seconds.... anything more and you could destroy the transistor!), you SHOULD have continuity between 1 and 2.

I am curious to hear more about the issues with the crank reluctor blade and how that all came to be.Doug C41092.8954512384

You need to use the appropriate blade for this vehicle... they have changed a few times and being a 3.8 it is a significantly different ignition design than previous years. If there is any question I can get you the appropriate part number with your VIN to make sure you get the right one.

You can wait until we are done; I am just obligated to post as an answer to give you the opportunity if I am not requesting information. Whatever you are comfortable with, I only ask that if you feel the need to use one of the lower two negative ratings you let me address the concerns causing that prior to giving a rating.

You really need to have the correct parts... while there are some other vehicles that may plug in and may look similar, if they aren't identical, there is a reason. You can not trust it to plug in and be good, as in some cases this can actually cause damage even though it appears to be correct (nothing with your vehicle rings a bell in that respect, just giving you an idea of how different things can be).

From the website, it is difficult. You would look the part up by the catalog, then when you order they will ask for your VIN and they will verify the part prior to shipping.

Conversely I work for Mitsubishi and have access to their parts database...if there is something you need to order I can always look up part numbers for you, you can save up a bunch or whatever... it is not a big deal.

I got it, thanks!

Please keep me posted with your findings; I am curious to hear what you find, as the situation sort of escalated as we spoke, so I am interested in finding out if it was washing related damage or even something the other shop did etc.... It will be interesting to hear the result.

I will be here if you need anything else.

Hi,

With the non-programmable key the reaction from the security light will be different. If you attempt to start the car with a dummy key the light should blink about 10 seconds after attempting to start.
Note that if you try repeatedly to start the car with a dummy or unprogrammed key, the system will lock up entirely. If this happens, even a correct key will not start the vehicle until the ignition is left in the On position for about a half hour with a working key.

Well, in your situation it is a bit more difficult. Normally, you can tell by the car not starting :)

For you, what you would want to do is put a noid light or test light across one of the injectors. If the system is locked up, the injectors will not pulse. If the injectors pulse normally, the system is not locked.

Theoretically, if the system were locked, the over ride should not work. If the system locks, all functions are supposed the cease until the waiting period is over. I don't know off the top of my head if the light would continue to flash or not... normally it only flashes for a short period (30 seconds, etc), however it is not exactly common to lock the system up in my position, so I couldn't say definitively.

If you had access to an immobilizer capable scan tool you could just re-register the key to bypass the 30 minute wait.

Double check your spark first, if you still only have one coil firing, you need to monitor your crank sensor on a scan tool and see if it is reading.
It is possible to have locked the immobilizer, but considering you just started messing with the dummy key, we know it isn't your primary issue regardless.

If the crank sensor is bad (and in some conditions the cam sensor as well), you will get one coil sparking and no fuel pulse; you can get occasional pops from crank case vapors igniting as well as if the sensor reads good for a split second and fuels momentarily.

Check those sensors like we discussed at the beginning.

Most likely just a faulty coil, though a bad pcm could do this as well.

The coil has 12V any time the key is on as well as ground. The coil is commanded to fire by receiving a low voltage trigger from the pcm. In theory a trickle of voltage from the pcm could cause the coil to overheat... most likely it is just a coil failure though; this goes double if it is an aftermarket coil, we have huge problems with aftermarket coils swelling and even exploding on these vehicles.

Well if the moved coil swells and fails too, you know you have an issue there from the pcm or the wiring. If the problem does not reoccur, it is likely the coil just failed. Hard to say with so many variables that have turned up since the initial post.

See what shows on the scan tool. I am interested in if there is a valid crank signal/rpm signal or not indicating a working crank sensor.

It's no problem. If anything sounds strange let me know and I'll review it. I will be in shorter hours tomorrow but will get with you as soon as I am available.

Hi,

All things being equal, if you have spark on all three coils (5/2, 1/4, 3/6), the engine should run.
If there is no fuel pulse on the injectors, I would be most suspicious of having locked up the immobilizer. The fuel pulse and spark pulse are both from the same input, the crank sensor... so if you have spark normal, the fuel pulse should be normal too provided the immobilizer hasn't been tripped like we discussed last night.

Correct, it would have unlocked.

Ok if you have only two coils it will not likely run at all... you may get some hiccups but that would be it. Before you said 4 and 2 and 3/6, I took that to mean the 1/4 and 5/2 coils.

The fuel gauge will show when the key is turned to on... it does not need to be running.

I would be suspicious of the connection at the tank, however if it has just been added be aware that small increases can take quite some time to register. The reason for this is that the gauge does not respond immediately to level changes in order to prevent the needle from going up and down while going over hills, parking at angles, etc. In order for it to spring up into position after being low, it needs to be a good half tank increase or so, otherwise it can take 15-30 minutes to rise in some circumstances, depending on the starting point.

Before getting all side tracked there is an easy solution here, they need to just pull the fuel supply hose off at the injector rail and see if you get fuel. If you do (ideally we would want a pressure reading, but again we don't need to get overly sidetracked), then we know not to worry about the amount of gas in there anymore. Honestly I a bit surprised that they would not have checked this first prior to making that assumption, because even if they did and there was no fuel, further inspections would have been necessary to verify pump operation, etc, which wasn't mentioned.

Hi,

Which parts are you trying to order? I will check availability to see what the problem is.

Thanks.

Both of those part numbers are correct for a 2003 3.8 Montero. Checking US stock, both are fully available.
MD357274 there are about 20 left in our warehouses in addition to dealer stocks, and MD360196 there are about 60 left in our warehouses in addition to dealer stocks.

Mentor does not have either of these in stock at this time, however that should not cause any problems with you ordering them (the majority of parts they will have to order prior to shipping).
Did someone contact you and tell you they couldn't provide the parts, or what exactly happened?

Wow, I'm sorry to hear that. I have had much success with them shipping internationally in the past. I can only assume that your particular destination is somewhere they will not ship to, which is a first for me. I have one customer in Singapore that has ordered from them several times.

I do not have any other shops that are as reliable or that will ship overseas unfortunately. Your best bet would be to look into some UK based dealers that would be a little nearer to you and you might have some luck with. Failing that, and with no dealers near you, you may be forced to go with aftermarket parts.... I'd strongly recommend exhausting all of your efforts finding genuine parts first, however.

If you have a friend in the US, have them place another order for it.
As I mentioned before, there is plenty of stock of both parts in our warehouse. Mentor rarely has items "in stock" at their dealer except extremely common failure parts, no different than any other dealership. When you place an order with them they then place an order to the warehouse, and 2 days later they have a part to ship.
Looking at the part availability, the only reason I can see why they said that was reinforcement to avoid shipping to your location.

Have your stateside friend place an order and see what happens, I'm sure that should go through fine. If not, we can try www.mitsubishipartscenter.com, another online dealer. I do NOT have personally experience with this dealer though, only Mentor.

Hi,

One tooth off is not going to interrupt your spark function on this model, however the engine will not run perfect. Two teeth or more on the driver side head can prevent spark function however, as the driver side head timing is monitored.
If both cams are off, you certainly want to correct the timing before going any further.

No problem.

Unfortunately new is the only "sure thing" and it does come at a very high price tag. The other is worth trying, again just make sure they have a good guarantee etc.

Very true; it is unfortunate but the burden of truth to show its there fault is on you.

Yes there are several different sensors and reluctors. You having the 3.8 Montero, yours are different from all the others.

The only thing worth noting here is that you say you are seeing spark advance... does this mean you are seeing engine RPM as well (your voltage reading looks to be the case)? If you are seeing engine RPM, the reluctor and sensor are working and your problem is elsewhere, likely just coincidental that the change occurred during the reluctor replacement.

Hi,

The Sport and 3.8 reluctors are very similar. Can you take a picture of yours so I can see what we are working with?

As I said, they are very similar however they are different. If I remember right the stepping is different off the gear, however I have never had both of them off a vehicle at the same time to purposefully compare as I'm sure you can understand.

Originally there were issues with the blade breaking, then an incorrect gear and blade being used etc... with so many variables I would really need to see what we are working with to get an idea of what is right and what isn't. There's too many chefs in the kitchen, if you know what I mean, and it is making it more than a bit difficult to get an idea of what all has transpired with regard to this reluctor in particular and what is and isn't an issue with it.

No worries.

Lets see what we are actually dealing with so we can see what is and what is not a problem.
When you do that if you would like to bring me up to speed on the current situation with the vehicle as well that would be great (what is currently working, what isn't etc).

No real readings at this time unless there is something noteworthy (for example no RPM signal from crank sensor or pending faults etc)... just refresh me on the exact state of the truck. For example:

Cranks but doesn't start or starts but runs poorly
No spark, spark on some coils, normal spark but won't run

And so forth. It has been a while since we spoke so I would like to be sure I have an accurate understanding of the current condition of the truck.
No rush on that, just let me know when you get the pictures of the different reluctors etc so I can evaluate it all.

Thanks.

I don't see anything unusual about that reluctor, how exactly is it different?

With regard to your codes:
P1601 - Is the throttle body unplugged?
P2108 - Same question
P0758 - Transmission... not a concern right now
P0443 - Evaporative... not a concern right now
P0183 - Malfunction in fuel module... has the fuel pump been removed or disconnected?

I apologize, the first picture did not load previously, I see the two pictures now. Sorry that was a bit confusing.

The one that is on the vehicle now (and the one on the right) is the correct reluctor. The one on the left is the Sport reluctor which will give you incorrect ignition timing. If you have a 3.8, you want the one that is on the car now in the last picture.

I am quite concerned about the throttle body malfunctions. If you take the intake hose off and depress the gas pedal with the key on or cranking, does the throttle open up?

This is probably not a good thing.

As the codes indicate, there is a communication issue with the throttle body... now on some of these, depending on revision, they will not open if the pedal is depressed with only the key on (which is why I suggested cranking as well). With the age of this model, it should open even just key on, but cranking it would if not.

When you monitor the RPM signal on the scan tool, it clearly goes from 0 to cranking speed (100-250 RPM)?

Any other points of interest regarding how this all came to be?

Unplug the throttle body and check between pins 5 and 6. These will be the two to the far right with the locking tab is on top. Let me know what resistance is there.

Thanks, XXXXX XXXXX good.

Pull the throttle control relay and verify if you have 12V on pins 3 and 4 with the key on.
The throttle relay is located below:

If you DO have 12V on two pins, swap the relay with the MFI relay and then check to see if you still have power on those two throttle relay pins.

Good.... that doesn't help me any, but good :)

If you clear the faults, does the P1601 return?

In case it doesn't go without saying, make sure the relays are returned to their proper places and the throttle body is plugged back in first :)

That's very not good.

Is there anything else noteworthy going on, specifically any accident damage, rodent damage, or someone poking/cutting at wiring?

Go through your wiring and look for anything out of place... not just cut wires but harness routed wrong, etc... anything that could indicate someone was in there and may have done something that would justify digging deeper.

As it sits right now, the P1601 is indicating that there is no communication between the throttle unit and the PCM. The PCM checks out OK on the motor drive as well as the position sensor, and the power supply for the throttle unit that goes to the PCM is energizing properly. Ideally we would want to check to see if the power from the throttle relay is reaching the PCM, but lets look for obvious issues first.

Based on the testing thus far, the service manual is going straight to PCM replacement... but keep in mind they do not account for outside influence, they are strictly going to diagnose components etc.
Copied from the service manual for P1601:

To prevent damage to scan tool MB991502 or MB991958, always turn the ignition switch to the "LOCK"(OFF) position before connecting or disconnecting scan tool MB991502 or MB991958.
(1) Connect scan tool MB991502 or MB991958 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) After the DTC has been deleted, read the DTC again.
(4) Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is DTC P01601 set?

YES: Replace the PCM.


Obviously not a good thing if we can't find any wiring issues. If all looks OK we will go on to a few PCM checks, but there is very little to go from at that point.
Also keep in mind that this is still potentially an "additional" problem. How it is affecting the rest of the vehicles ability to run isn't set in stone at this point, but obviously it is a problem that will need to be addressed prior to the everything being 'fixed'.

No problem.

I will be tomorrow about 4-5PM your time, but if you come up with anything of interest feel free to post it in the meantime and I will catch up as soon as I get to work.

Hi,

Thanks I did not get your previous message for some reason.
The throttle body will click about 6-10 times at key-on, which is normal, that sounds like that may be all that is. Try unplugging the throttle unit and then turning the key on to see if it ceases.

Yes if your RPM signal goes from 0 to 125 it is definitely seeing movement. It is a hall effect sensor so there isn't a lot of room for it to erroneously give a signal, they just don't work that way. It is possible to have it give a signal and be a no good signal.... but to be non-functional and still give an RPM signal is nearly impossible.

Sounds like perhaps the purge solenoid...did it have two hoses attached to it? Kind of odd for it to be making noise with the engine off though.

The RPM doesn't really have a cranking specification, though we usually see closer to 250 (the 125 I was just rounding off your figure from memory). Slow cranking speed can affect the rpm obviously. The only way to test for certain would be to use an oscilloscope and verify the squarewave is occurring.

With the two throttle body codes we are in a bit of a pickle... P1601, if there is no wiring damage it is indicating a faulty PCM. There is no further testing for this provided in the service manual... simply replace the PCM (Easy for them to say, I know).
For P2108, this normally indicates a PCM failure as well, with all other things being equal (previous inspections we made and no wiring problems). The only extended testing that would be done would be throttle position inspections.... however these are automatically out of the question due to the throttle unit not moving at all.
If your scan tool supports it, you can check your TPS Main voltage is within range (0.35-4.8v), and if it is out, double check your fuses again to make sure nothing was overlooked (if not, indicating no power from PCM). You can also check your APS (gas pedal) sensor for normal output... but again this won't affect anything if the throttle unit is not powering up.
I think this 2108 is more likely to be a side effect of the 1601 were I to guess. Normally the only time we see throttle unit failures is with paired with a P2100... when that one comes up, the unit is dead typically.

This is a bit of a tough situation as you have one and possibly two quite expensive parts that are being indicated faulty.

Is there any back story I missed/forgot about how this all came to be? It sure seems like there is a whole mess of problems to have cropped up all at once.

Hm... not exactly sure what that is, I would probably need a picture.... we are getting a bit sidetracked at that though; it is likely the emissions valve and maybe even related to that 443, but certainly should prohibit starting.

The throttle body being dead (or at least unresponsive) will prevent starting though.

When you say "another PCM" is that just in general, or did you replace the PCM once before on this?

Oh okay, I was getting a bit worried there that maybe you had had it swapped and that is where the throttle malfunction came from.

I really really hate saying a PCM is bad because it is so rare, but that sure seems to be the case here.
I just wonder if that was the issue all along and the additional problems may have stemmed from the repair shop poking around?

Pin 2 I believe will be the position sensor voltage in. Then pin 4 is voltage out... which is how the PCM determines where the throttle is set. There are two throttle position sensors in the throttle unit that use pins 1-4 to operate.

The motor receives power and ground on pins 5 and 6.

The throttles have a heavy spring on them.... they will not open easily by hand, however once they start opening it does not get any harder or rough etc. It is strong enough that if it was open under it's own power (gas pedal propped down for cleaning, for example) and your fingers were in there and it snapped closed, you would mess your fingers up pretty good.

If you wanted to check outputs at the PCM, you would look for the following:

105 no test available
106 (throttle pin 2) TPS input 4.5-5.5V
113 (throttle pin 3) TPS output voltage through throttle (can not be tested disconnected) 2.2.-2.8V closed, 3.8-4.9V open (by hand)
115 (throttle pin 1) TPS output voltage through throttle (can not be tested disconnected) 0.2-0.8V closed, 3.8-4.9V open (by hand)
133 (throttle pin 6) motor + > Battery voltage at 'fully open' then decreasing slightly as the motor closes (2V roughly)
141 (throttle pin 5) Motor - > Battery voltage at 'fully closed' then decreasing slightly as the motor opens (2V roughly)

That is your EGR valve.

It shouldn't click though. It is PCM controlled so it is anyones guess if it is malfunctioning or the PCM was powering it up in error.

It does not rotate, just opens to allow exhaust gases into the intake under deceleration, etc.

No problem.

Unfortunately I do not see any other place to go.

Until that throttle body is functioning correctly, the engine is not going to run. While either the PCM or throttle unit can be at fault, the tests at the throttle unit all come up OK, and with no obvious wiring issues the PCM is going to be the required next step.

Be aware that if you have immobilizer on this vehicle (which you should), the keys will need to be programmed to the new PCM. We will at least be able to verify throttle unit operation though before hand... the keys will just prevent the injectors from working, nothing else.

Hi,

Unfortunately you really can't easily.

You have one thing in your favor, and that is Mitsubishi changes the connector configuration regularly on the PCMs to avoid being able to plug them in to the wrong vehicle. Not 100% of the time, and certainly not to the extent that one year-off PCMs would definitely be different, however it is a good shot if the connector configuration is the same you are on the right track. Remember not just to look at pin shape (needle or blade, narrow or wide etc) and connector count/pin count.... but also the alignment slots that match the grooves in the connectors. If these are different, obviously the connectors won't plug in. These are all changes they make to try to avoid putting the wrong PCM in.

IF it does fit, you aren't out of the woods yet. After that the only thing that you can do is plug it in, connect a full feature scan tool and read the PCM part number that is coded into it. Code readers and generic scan tools can not do this. You need a high end scan tool with full two way communication to do this... apart from the Mitsubishi tool, Launch X431, SnapOn Modis, etc those types of tools.

If you can... I'd keep looking just in case you find something else, however if you can verify 100% that the pin type, count, orientation and alignment slots match then you have a 'good' chance it is right. Given the many number of years this truck was built and the very few number of years that got the 3.8, I would say the odds are against you though.

Again, I would play it safe and keep looking first.

There is some confusion regarding the anti theft system on Mitsubishis when dealing with people that don't work on them exclusively.

The key memory is stored in the PCM, requiring reprogramming of the keys after replacement. However, on older models, specifically 2001 and back, there was a separate immobilizer ECU that had to be replaced at the same time as the PCM. The reason for this was that the immobilizer ECU hard-coded to the PCM at first use, so if you replaced the PCM, that immobilizer ECU would never work with another PCM ever again.

Mid 2001 this stopped however.and late 2001 and 2002 on do not need the immobilizer ECU replaced with PCM replacement. For reference, here is the bulletin Mitsubishi replaced when this problem was eliminated:

You should get spark regardless of key programming.

The good news is that your codes are resolved, I take it you have regained throttle body operation at this point?

Both the ignition and the fuel pump are controlled by the crank position sensor. If the crank sensor is not detected (and no RPM reading), then you will have neither spark nor fuel pressure (or injector pulse for that matter).

If you put the new PCM in you have no spark/fuel pump/RPM signal, and when you put the old one back in you have spark and RPM signal but no operation (closed throttle body), is that correct?

Sounds like there is a bad driver in the new PCM.

The only other thing that would affect the crank sensor signal would be if the PCM wasn't turning the MFI relay on, etc, however if that was the case you wouldn't have throttle body control or the ability to check codes. And of course if the crank sensor or the wiring to it was an issue, you wouldn't have crank sensor operation on the old PCM.

If the throttle body is not responsive, it will be unable to adjust idle accordingly. On a traditional system there would be a secondary air control valve that would adjust as needed to regulate air flow. On a electronic throttle the actual throttle plate adjusts to set idle. If it doesn't move, you can only 'get lucky' with it being able to idle or not depending on it's position, and of course no drivability will be possible.

As I mentioned before when we first got to that problem... it may not be "the problem" but it definitely is "A problem". Theoretically if there is nothing else wrong it is possible that the vehicle could run with the throttle inoperative, it's a crap shoot though. Regardless the throttle problem needs to be repaired (new PCM, as we already verified). Now, assuming there are no other problems, you just need a 'good' PCM.... that it runs on ether with the old PCM is a good sign but again until we have the one problem resolved without creating a new problem (no crank signal), we can only speculate.

no problem

Good luck!

Hi,
To be clear, when you say it gives no error codes, you mean you can scan the system and there are no codes, not just that the light does not come on right?

The numbers are of no real interest... the base part number is XXXXX Typically we use the engine/AT revision to see how recent the software is, but it doesn't look anything like that. As long as your base part number (MN132937) is correct you have the right unit.

Correct, this system should only affect fuel pulse on spark whe the anti-theft is triggered (unprogrammed keys). It sounds like they aren't going to do anything for you until you buy a new immobilizer ecu. I maintain there is no reason for this though.

Refer to the bulletin I posted previously on 8/23 indicating that it is no longer necessary after 2001 on all models.

Thanks, XXXXX XXXXX to make sure we were clear on the current operation and we are.

For an 03 your immobilizer ecu ("theftproof" they call it) should be MN141592 and lists for about $305.
This is only an OEM part.

The immobilizer ecus from 2001 onward are not hard coded... which is why you don't really need to replace it. It sounds like this place isn't going to honor any warranty unless you replace it though, which rather stinks.

No problem.

Good luck!

Hi,

It is possible, I have not had one of these apart nor do I know what revisions they may have made... if it is the same part number on this model there should be no difference, however that isn't to say that the PCM cover is the right one for the board either... all bets are off really.

I take it this place is just a used PCM store and they don't do any rebuilds?

Hi,

Getting a unit from Mentor is possible but not 100%. For part number MN132637 there are only two left in the country, both in the Los Angeles warehouse.

For a 2003 you should only have to program the keys. Right around this time they added VIN writing to the PCMs too, and yours could go either way.

There is little to no chance that the PCM won't work... given that we know for fact that the two PCMs you have used both have faults within them (the throttle wouldn't work with one but did with the other; crank sensor wouldn't work with one but did with the other), we know there were no external factors causing the problems. If there were, the same problem(s) would be evident on both PCMs.
The only risk of if not working would be if you got a used/returned unit, which leads us to your last question... no there is no return of electronics components at all (meaning the odds of getting a used/returned one are almost zero... only if a dealer snuck one in as an unopened return dishonestly).


To program the keys (and write VIN if yours is in the last batch) you will need the MUTIII scan tool.

Hi,

Unless it needs a VIN write (which again yours could go either way but I would not suspect it since that didn't really take hold until 05+), it only means you will need to have the keys programmed to it.

"Programmed" is a bit of a blanket statement people use with PCMs, but those are the only two concerns you would have. Unfortunately both require a MUTIII scan tool though.

It is possible you will be able to use the over ride code.

While the over ride code is matched to the immobilizer ecu which of course won't change so your over ride won't change, the over ride feature started being discontinued in 2003, so it is hit or miss if yours still has the feature