Chrysler Repair Questions? Ask a Mechanic for Answers ASAP
Hi Michael, my name is XXXXX XXXXX for writing!
It sounds like a throttle position sensor (TPS) problem by your description. Thankfully, the engine controller may have made the decision for us by now with the code it has stored.
I'm pretty sure the 04 Pacifica supports the factory code-read feature, which is pretty handy in cases where you might not have a handy-dandy code reader. If it works... it works like this.
Hop in the vehicle and shut all the doors.Roll the key from off to on three times, leaving the key ON.Watch the odometer or information center in the instrument cluster for code display, followed by "P-done" or simply "done" when completed. Codes will be shown in their P-format, which will read similar to P0123...which is one of the TPS failure codes possible.
Erratic TPS output confuses the engine controller (PCM), making it think you have your foot on the accelerator, pushing it to increase engine speed. An idle up or ignition advance program is installed at that point and an idle speed increase is seen. Other conditions to create this condition may certainly apply, which is where the diagnostic trouble code comes in. You won't see a CHECK ENGINE lamp illumination while driving unless something is stored in PCM memory, so that would be our next step.
I see you're offline at the moment, so I'll move on. I'll be notified by email when you post a reply.
Talk in a bit, Ed
Hi! Any luck with the code read?
i am going outside to check now.
Very good. Give me a minute to check...
It's looking a lot like a manifold absolute pressure (MAP) sensor problem. P0068 describes a conflict between the MAP and TPS sensors (which should be almost linear) and P108 shows the MAP sensor circuit voltage to be high.
now we are getting some where.
By high, it means a voltage has been seen that's higher than what could possibly be generated on Planet Earth without a supercharger. Chances are good that the MAP sensor is responsible for the signal conflict and for producing an irrational signal. Once the PCM disregards XXXXX XXXXX MAP output signal, some hesitations on acceleration and even an artificially-low rev limit can be imposed by the engine controller.
The last code (P0522) is described as OIL PRESSURE SENSOR CIRCUIT LOW, which more often than not just means you have a bad oil pressure sensor. It faces a pass-fail test similar to what the MAP sensor did, but its problem was with too little voltage output, so I can't see a connection.
Is the map sensor hard to get to and replace?
No, it's actually pretty easy. I'm a bit fuzzy on the exact location, but it's on the top side of the engine and will be screwed to the intake upper intake plenum. I'll take a quick look and get right back to you...
It's located in the upper intake manifold (also called the plenum), which is the large bulbous plastic thing that lives over the top of your engine. Look at the driver's side-rear of the plenum for a 3-wire sensor that basically points at the brake master cylinder reservoir.
Three-wire sensors are rare in this area, so it should be the only one. Inspect it and the wiring harness-connector for signs of damage or detachment from the sensor. A P0108 can be set by disconnection.
Got it, what about the oil pressure sensor is that vital right away?
Ooooooooooo... tough call. I'm thinking you're OK with the crankcase being filled, but oil pressure indications always carry a certain amount of risk. That said, if you have no clatter in the engine that's just begun, you're probably OK on the oil pressure issue. It might be a 3-wire sensor also... I'm not clear on the circuit. If you have a minute, I'll look it up.
Ok i am going out to look at that map sensor.
The oil pressure switch is described as being in the same general area as the oil filter adapter... which is to say if you find the oil filter, you'll locate the switch/ sensor nearby. I'm still not clear whether this is a 3-wire sensor, so I'm going back in... be right back.
It shows to be simply a switch in this model, so it involves but a single wire. Voltage from the source (PCM/ engine controller) is sent by this single wire to the oil pressure switch. It then grounds the circuit when too little pressure is seen... or if the sense wire is shorted to ground by any source, including the wiring harness or a bad switch.
found the sensor got is removed from the pendlum having a hard time to remove it from the harness. I am afraid i will break something right now. Can it be cleaned or just replaced?
If you don't see any physical damage to the connector or terminals of the MAP sensor, just replace it. They can't be cleaned or serviced in any way. I'd like to see what output of the sensor is like before you replace it if you have a digital voltmeter handy... just to be sure.
nope it is in town in storage with my larger tool box. I slid out a red tab but from there i am not sure if I press down on a center tab and pull to remove from the harness.
Yep, that's it. The red locker needs to be clicked away from the sensor, then push the thumb release.
Look for any sort of water, corrosion or anything that doesn't look right in the terminal area.
I am thinking i can get it tomorrow when the sun comes up. I may also be able to borrow a neigbors voltometer.
I'd like that. It's unfortunate to replace something that's not needed and while it's quite probable... knowing what the circuit shows might save us some trouble and expense.
so once I click Accept does that end our chat? What do I want to do with the meter?
Don't end the chat yet. I'll post some info shortly on what to test... on which wire... and what to expect. What part of the country are you in? I ask because altitude has a great deal to do with MAP output at key-on...
I am in nm at about 8,000-9000 ft
Oh wow. That beats me! I'm at 6000 feet in the Denver area.
You must have some gorgeous nights out there!
Yes we do, the school in the community I live in only has 160 about kids k-12 so it is very rural.
Wo.... I miss the clear starry nights since we sold our property up in South Park. It was at about 9500 feet and just knocked my socks off.
Well, have a great night and I'll have something waiting for you tomorrow when you locate the meter.
Talk later, Ed
Let's set the meter to 20 volts DC, ground the black test lead and test the signal wire for voltage with just the key on (engine not running). This wire is violet/ brown and needs to be tested with the sensor connector installed on the MAP sensor, so piercing the wire or backprobing the wire through the rubber weatherpack at the wire end of the sensor will be needed.
Backprobing is preferred to avoid wire damage, but the pierce can be repaired later with some nail polish or Liquid Electrical Tape, a brush-on sealant sold at most hardware stores.
To backprobe, you'll probably need an extension because most voltmeter test leads don't have enough reach to get all the way to the conductive terminal deeper in the connector. A paper clip works well for this.
I'd expect to see something around 3.0 volts or so at your altitude. Sea level renders about 4.5v... we see 3.7v here in Denver, so if you see something in this range, the MAP sensor is doing a decent job. The code that was set suggests that you could see something over 4.8 volts, which brings us to the next test if found...
Next up would be the sensor ground circuit. While it's only a ground... just like what you can find anywhere on the vehicle... it's a circuit that runs through the PCM to be electrically cleansed a bit to remove external "noise". It should show almost zero volts when backprobed using the same method as for the signal circuit.
Voltages of 0.05v or so are OK, but anything at or greater than 0.10v mean the sensor ground circuit isn't in good shape, which can drive your MAP sensor voltage up.
Traditional testing of the sensor ground circuit with the ohmmeter function should show 20 ohms or less of resistance to battery negative (ground). I prefer the functional voltage test because it shows in no uncertain terms if the circuit is in good shape. If voltage is left, it's not being drained off properly, which is the sensor ground's job.
I'm sorry.. the circuit is dark blue/ dark green. You'll need to know that.
Last is the 5v feed to the MAP sensor, which is colored pink/ yellow. It should read a constant voltage of around 5.0v or so whether the engine is running or not.
Now, if these voltages check OK, you'll need to start the engine and recheck the previous two circuits to see what happens. The signal circuit should change to reflect engine vacuum, which is a change in manifold pressure. Expect an idle voltage of near .5v or so in a working (and happy) sensor.
Since we don't know for sure if the codes you found are actually active, there is always a chance that things will test OK right now. Intermittent problems that cause these codes can still be caused by wiring issues, so trace the wiring as best you can back to the PCM, which is hidden in the area just forward of the left front wheel. Wiggle test the wiring while monitoring sensor output voltage (key on, engine off) to watch for any sort of change in system voltage. It should remain steady if the harness is not to blame.
If everything checks OK, I'd suggest clearing the codes by doing a battery disconnect of about 60 seconds. Reconnect, start the engine and even go for a ride if nothing turns up odd at first. Let me know what you find and we'll press on from there.
test 1 with key on
violent / brown 3.47 dk bl/green .01 pink/yellow 4.97 using paper clip method
test 2 with engine running
violent/brown 1.24 dk blue/green .04 pink /yellow 5.0 using paper clip method
As I was moving the paper clip the car started to stutter, I jiggled the wires and the car stalled. I then used a needle to penetrate the wires and tested with the key on every thing read .01,0 and 0 in the same order as above. I went to start the car now it will start and die right away.
did a code check again after disconectin the battery. only one p108
Sorry to keep you waiting. We had site problems with each and every chat... couldn't get 'em to load.
thats fine, glad your back.
Boy... I'm not sure if you have a MAP sensor problem or a MAP connector problem.
Something seems wrong there... you agree?
yes i agree
it looks like to me that the connector can be take apart also as there is a clip on the back where the wires go in.
I don't like the key-on voltage on the signal circuit for starters. And your idle voltage doesn't drop as expected... although that could be a reflection of actual engine idle weakness. See what you can do to determine if a wire is broken near the connector or if a connector female terminal is spread a bit, making poor contact. Pulling lightly on a wire as it enters the connector will sometimes tell you something when it just yanks right out. A good crimp connection should hold a pound or two of force, but weak connections just snap.
Remove the blocker chip from the open (terminal) side of the connector, then reach in with a super-tiny pick or screwdriver to lift the plastic tabs that hold the terminal in place. They pull out the back (rubber) side of the connector.
Some terminals offer enough access to the inner contact area that you can press the terminal spring inward with a pick tool. I'm not sure if that's the case here, but you can at least push the terminal back onto a MAP terminal to feel how much friction it generates... how tight the connection is.
i will go out side now.
OK. I'll need to go check in with more customers that have been locked out all morning, but I'll know when you come back by email notification. Good luck!
Ok wires are secure, none pulled out.
I removed the sensor from the connector. I took did a voltmeter test on the expose points inside the connector.
key on violet 4.87 dk bl .ol pink 4.97
engine on violet 4.87 dk bl .02 pink 4.98
with the sensor replaced on the penlum disconnected from the connector and the engine running the motor shuttered at inital acceleration then again at around 4000 rpm
Those look abut right.
A big stumble would be consistent with a disconnected MAP sensor. It's a really important input to the fuel system.
I think you're cleared for MAP sensor replacement, Michael!
And I'd probably do the same thing with your oil pressure switch. You might not be able to reach it without putting the vehicle on a lift, tho... It might be best left for the next oil change.
very good well i guess i will get the sensor thank you help. If you think that we are done i will click accept.
Almost. I'm going to check to see if there were any technical service bulletins for either problem you're having. It'll just take a couple minutes.
Nope. Nothing about erroneous codes like what you saw here. Sorry to keep you waiting... I'm a chronic worrier, always thinking I've missed something. I think you'll be good to go with the new MAP. What I'm going to do is to convert the chat to conventional question-n-answer, which will have a different look to it. But it means that you will be able to write back after accepting with no additional charge.
Well I just put on the new sensor. Note (the stock sensor would cost $75.00 - 125.00, the newer sensors for the models after 04 only cost $19.00 - 25.00) I got mine through napa under 20.00.
So any way installed, no engine light, no stutter at intial acceleration. While in Park or Neutral stutters at 4000 RPM. In Gear on the highway no stutter at any RPM I went through all gears except reverse.
So runs fine on the road, still stutters at 4000 rpm while parked and no P codes given.
No problems with the connectors I jiggled it while the engine was running, it did not shut off or stutter.
All and all I am happy to be moving again. if you have any suggestions that would be appreciated.