How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Geordie Your Own Question
Geordie, Mobile Mechanic & Motor Trader
Category: Car
Satisfied Customers: 456
Experience:  22 years of mechanical experience, and I am the mechanic in my own automotive partnership
Type Your Car Question Here...
Geordie is online now
A new question is answered every 9 seconds

My 1999 Ford Expedition will crank, but not start.

This answer was rated:

My 1999 Ford Expedition will crank, but not start. Fuel pump works, and the mechanical stuff is fine. It seems to have something to do with an electrical sensor. The emergency turn over fuel flow mechanism is set right. I acts something like a gear shift position sensor, or security system flaw. It had this problem a week ago and went away after opening the door with the key and not the wireless. It's back; cranks, no start. The "Theft" light goes off as I crank and the key is good (it started it last time). Any ideas?


Have you definitely got gas, spark and compression?

Geordie and 6 other Car Specialists are ready to help you
Customer: replied 10 years ago.
Reply to Geordie's Post: Yes, gas and ignition are good. Pump engages and last time it did this, once started, it runs great. Also, no codes reported in the system.
Oaky, the three scenarios which come to my mind are, no compression, no fuel being injected although a supply is available, or too much fuel being injected, and the last two are very highly likely to be caused by a bad fuel pressure regulator.

Is your vehicle multi point injection (more than one injector) and have you got access to an auto meter? (volts, resistance, dwell, frequency, pulse, etc...)

Customer: replied 10 years ago.
Reply to Geordie's Post: Geordie, Excellent thoughts. I know I've got compression (has failed, then restated and ran well). I do have a OBDII ( and no codes). I also have a volt meter if you have tests in mind.

I still feel something could be up with the security system...not sure. Last time it worked after same symptoms, all I did was unlock the door with the key and not the remote!

Could I try to spray ether in the throttle body and see if ignition occurs? Also, I have coils on all cylinders.

Keep up the great work! Rick
Hi Rick

If it was the security system I expect the starter would fail to turn because this one of the immobiliser targets, along with the fuel and ignition systems.

Okay, first of all, can you remove one or two of the spark plugs, clean them up, put them back in, turn the engine over a few times to try to start it, and then remove the same plugs and see if they're covered in fuel or not.

If they are covered in fuel, remove ALL of the plugs, clean them up, replace them, unplug all of the injector wires to disable the injectors, and then spray carb cleaner or the like into the intake as someone turns the engine over on the key. If the engine then tries to fire you have an overfuelling problem.

If the plugs are dry when you take them out, put them back in and carry out the same test as above with the inlet spray but do not disconnect the injectors. If the engine reacts to this then you have an underfuelling problem.


Customer: replied 10 years ago.
Reply to Geordie's Post: Good ideas Geordie...I'm on it. Wouldn't bad fuel feed issues start placing codes in the computer? Still no coeds, but you're right...have to check these ideas out.

I did try cleaning up the MAF with no effect.

Thanks for hanging in there for me. Give me a day or two...those plugs are a pain in the rear.

Stay tuned.


if the engine was running you may get a lean bank code or the like, but not always.

Codes are not always stored straight away, and they are usually stored after a full drive cycle (start up from cold, driven until at full operating temperature, and then switched off), and sometimes, the light will flick on then off again and you will not notice it, which means a code is stored and you know nothing of it coz you missed the light!!

Another thing to remember is that if you have no spark then you will also have no fuel because the computer will defend against damage to the convertor by neglecting to pulse the injectors.

I will be away for two weeks from Saturday because I am going to Turkey to get blown up.... I mean on holiday...!!!

Basically, if the spraying of flammable subtances into the intake as above produces no attempt to fire whatsoever then you have a NO SPARK scenario, and tis would entail checking the ignition control module, crank sensor, etc.

Hopefully you will get back to me before saturday night and I shall impart some more advice on what you tell me.


Regards XXXXX XXXXX wishes

Customer: replied 10 years ago.
Reply to Geordie's Post: Geordie,

Your good, and your advice is great. This is a unique issue that when all is said and done, could be a maze of different sensor, electronic, and modules. You've done more than enough so I'm going to release the $15 next opportunity. You've imparted much more than that amount of experience...all good stuff. Thank you.

I'll get back on the fuel/ignition situation, but may not make it before your travels(I spent several weeks in Ankara with Roketsan as a rocket scientist on loan for NATO out of ARC and Aerojet). I loved the country, and yet saw too little of it...great people. Have fun, be safe.

So, Godspeed to ya' and I'll post you after checking your recommended elements. My fear is that a Ford dealer (unless its a known flaw, they've quietly experinced before) would begin replacing "possible" faulty equipment until I go broke. It'd be nice to narrow it down further, but we could spend a lot of what iffing on this one. Let's hope it's a fuel/ignition matter, and not an obscur MAF or ECM issue.

All the best...I'll keep the thread going, but wish you well my friend. You'll get high ratings from me.

Regards, Rick

PS. No it's not the gas cap either...been there.
Hi Rick

Well, now I know where to come if I have a fault with my rocket!!!

It is definitely not the gas cap because the car would start and run, then lose power and give up.

It is not, in my opinion, the MAF sensor, because it is ignored until the engine fires and so the engine would start and then die. You can, however, prove me wrong buy disconnecting the wiring connector and trying the car.

Whilst Spraying into the manifold with clean dry spark plugs fitted:-

If the engine fires with the injectors disconnected but not with them connected then you have an overfuelling issue, and you would need to check the fuel pressure regulator and the coolant temp sensor, but my money out of the two would be on the fuel pressure regulator. It won't be the O2 sensor because this ignored until the engine warms up.

If the engine fires with the injectors connected or disconnected regardless then you could have an underfuelling problem, and once again my money would be on the fuel pressure regulator, with a secondary check of the coolant sensor.

If the engine does not fire at all in any way shape or form then you have an ignition issue.

Your best bet is to purchase yourself a cheap fuel pressure gauge and check the fuel pressure. If the fuel pressure is okay then we can move on. ost the pressure readings here.

I can read the thread using my mobile phone, and I can PM on my mobile phone so I will keep an eye out for you and PM you if my roaming contract kicks in, otherwise I shall nip into an internet cafe for half an hour.

Regards, XXXXX XXXXX and many thanks

Customer: replied 10 years ago.
Reply to Geordie's Post: Geordie,

I agree with your assessment and will act on it as soon as the torents of rain let up...not your basic 3:30PM thundercloud flyover!

I've been researching way off into the weeds and while I'm waiting for the rains to let up, my gut keeps taking me to something like the PCM or keyless entry security stuff. I know I've got to rule out the fuel and ignition scenarios, so I'll be back on those items. I also read somewhere that (might be a tech service bulletin on this) folks with my vehicle have had issues with a quirky vapor lock that involves a half full tank that at the right level, introduces vapor lock bubbles in the fuel feed line. Adding a few gallons of gas in the tank is the suggested fix...gonna try this too 'cause it's way easy.

The damn thing ran perfect last time it did...then the crank, no start, and then mucking with the wireless entry fob (lock/unlock, etc.) followed by opening the door with the key...put it back to running! ...for about three days.

I've been looking over the Ford TSBs and service manuals and there are whole sections ( and a bulletin or two) dealing with security entry communication SNAFUS that allow crank, no codes showing up, though. Items include: erasing key codes by two quick ON/ACC/OFF ignition switch cycles...keyless remote entry faults...PATS (passive anti-theft system) module...PCM (powertrain control module) module...Fuel pump relay...bad key codes from ignition key, etc. etc.

Of note is that the key pad entry on the driver side door has never worked...but everything else does. Even the "theft" LED stops blinking after a 3 sec power cycle?.!

So, I've got some simple checks to try along with the fuel and ignition checks...marked out the MAF as a cause (thanks).

I'll keep you posted as soon as I can get under the hood. I'll check relays and fuses again, they come up in the TSBs relative to this kinda mess as well. Can you imagine...over 267 TSBs!

Well, best regards XXXXX XXXXX travels for now. If you have any away in the meantime.

Checked off flywheel and starter solenoid cranks the engine and has compression (eventually kills the battery. Don't worry, I'm easy on the cranking...won't overheat the starter, etc.

Keep the cards and letters coming!

FloridaDomer...GO IRISH!