My Car Is [Still] Broken. Please Help!

dba

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2003 Lincoln LS V8
181k miles
New MAF
Coils, Plugs, Gaskets
New Battery
New Fuel Pump Motor
New Fuel Filter
Brand new 91 octane fuel
Cleaned gas tank

The Issue: The car runs perfectly fine on startup, and it will run and idle perfectly, you can even drive it. But after 5 min or so, the car dies, no strange noises, no check engine light. It dies like someone turned the key. After it dies, you can always start it right back up and it will run for a while then die again.

I've been dealing with this for a while, and eventually tried to sell it because I need it gone, and need my money back out of it. (Not that it is worth that much lol)

"WTF" moment: I recently drove it and while i was driving it, the car started revving itself then stalling and revving and stalling before finally dying. This has happened before prior to doing the gasket job. Doing the gasket job fixed it. But it started happening again. After it died i restarted it and it did that whole revving thing right on startup. right after starting it it immediately revved itself to redline and then died within 5 or so seconds. I let the car sit for 20 min to get a video camera to film it. I started it up with a camera rolling, and....it runs fine! Its perfect. The only thing I didnt do is drive it till it died to see if it was miraculously fixed.

So you might think it is a computer issue, but other than the dying issue i stated earlier, there is nothing wrong with it. no noises, no lights, nothing to indicate it is a computer issue, and everything functions perfectly.

Ive gotten 3 suggestions that it is the crankshaft position sensor. What do you think? Im going to go out and unscrew the sensor and test it.

Please help, I have to get this car out of my driveway, running or not.

Also, the car is in near perfect cosmetic condition. It seems like it was well taken care of (aside from high mileage) oil changes on time, previous maintenance. (not with the car, I did my own history research on it) not sure

Help!!!! (please)

Lmk if you need more info like photos videos if that will help?? oh the joys of ls ownership...
 
...Ive gotten 3 suggestions that it is the crankshaft position sensor. ...

Your LS has two camshaft sensors (in addition to the crankshaft sensor). Your symptoms do not at all suggest that it is either camshaft sensor.

It should be clear by now that throwing parts at it is not going to solve it. You need to properly diagnose it, or get someone else to do so.

Going purely on your symptoms and the assumption that you have eliminated the possible mechanical issues that you indicated, it really sounds like a defective PCM. I don't know why you are so sure that it isn't. The PCM only controls the engine and the transmission. Everything else is controlled by other "computer" modules.

You can send your PCM to this place. Lincoln LS ECM / ECU Repair & Return - SIA Electronics They can test and correctly diagnose problems with it. (You do need to indicate the problems you are having to them.) Testing is $90 if no problem is found, or $170 to repair it if something is found.
 
You say that there is "nothing to indicate it is a computer issue".

Except for everything you described is something that could be a computer issue...


You think it may be a sensor? well anytime there is a problem that could be a bad sensor, the possibility is still there that the sensor may be fine and instead could have a wiring problem or a problem with the device controlling the sensor (computer).

If you think it runs perfectly fine at times, that leads me to believe that (while its not for certain) its not a mechanical problem.



also the fact that you have a run away engine that is heavily controlled by a computer, especially the throttle, really makes me believe that there is something wrong with your computer.
 
I had a Ford five hundred sedan a few years ago with a similar issue . It would suddenly cut off as if someone turned it off with key. My issue was a Drive-by-wire Throttle body problem. With that said I replaced the throttle body assembly car ran better and never had an issue.. I own a Gen 1 ls8 currently non Drive by wire. I believe your 2003 could probably be Drive-by-wire. Worth a look
 
Correct of the change in throttle actuation between '02 & '03. You might source one from a bone yard (inexpensive) before digging into the ECM.

KS
 
I believe your 2003 could probably be Drive-by-wire.

it 100% is (as long as it is an 03...)





the biggest thing making me think its not a TB problem is the run away. even if the TB was bad and opened the throttle blade all the way, the motor would not just run to redline, it would need fuel for that.
 
right after starting it it immediately revved itself to redline and then died within 5 or so seconds.

I feel the same in regards to the fuel and questionable TB issues. Could the fuel remaining in lines of fuel system was depleted within the 5 seconds @ redline; then causing engine to stall as the OP mentioned. Not sure if it relates to the TB ,fuel or ECM. Without any engine error codes makes this hard to determine. As mentioned a "tester" TB could be found at local Junk yard for fairly cheap when compared to changing ECM or diagnosing a fuel issue. Good luck to the OP
 
i...the biggest thing making me think its not a TB problem is the run away. even if the TB was bad and opened the throttle blade all the way, the motor would not just run to redline, it would need fuel for that.

I agree. I'm 99.9% sure that if you forced the throttle open (or some defect there caused it to open) that the PCM would put the engine in ETC failsafe and cut fuel by not opening the fuel injectors. It really sounds like the PCM is going crazy.

...Could the fuel remaining in lines of fuel system was depleted within the 5 seconds @ redline; then causing engine to stall as the OP mentioned. ...

The PCM does not cut fuel by turning the fuel pump off, it cuts fuel by not opening the fuel injectors. There's no question on that. Fuel in the lines is not a factor.

Possibly it stalled because when the PCM went crazy, it stopped sending the correct signals to the REM, causing the REM to turn the fuel pump off because it thought that the engine was not running.
 
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Thanks for all the help! The car is drive-by-wire

The revving/stalling issue only happened the one time, almost like a fluke which seems like a computer issue. The only other time it did revving and stalling was prior to doing the gasket job. But after I did the gasket job it was still doing that, and disconnecting the battery to reset the car with new plugs/coils is what actually stopped it.

I like the throttle body idea, and in this car's maintenance history it shows that in '08 the throttle body was replaced once before. What does that mean? (other than that the throttle body has been replaced once before)
How hard is it to remove the throttle body? Ill definitely check out pick 'n pull for another one.

Where is the pcm/ecu located on my car? ('03 Ls v8)

i cant spend much money, but should i replace both. itll be cheaper to test a different throttle body, so im going to try that first

thanks again for all the help.
 
Update: pick and pull only has '00 and '02 ls. and they arent drive-by-wire. ebay has whole assemblies, but im not spending $100. does anyone know the name of the throttle control its self? and would just the sensor fix it do you think?
 
The throttle body is easy to change.
The name is the throttle body. It's a housing with a throttle valve, a servo motor, and a TPS. you can replace the TPS if you want, but that won't be the problem.

You can replace the throttle body if you want, but that isn't going to be the problem either. It almost certainly wasn't the problem is 2008 either. The problem very likely was EMI/RFI from marginal coils. Those same coils probably fried the PCM.

The PCM is behind the glove box, attached to the firewall: 2006 Lincoln LS Workshop Manual

s6x~us~en~file=a0064919.gif~gen~ref.gif

Item Part Number Description
1 14A464 Powertrain control module (PCM) electrical connectors (3 required)
2 N621927 PCM nuts (2 required)


s6x~us~en~file=n0004807.gif~gen~ref.gif

Item Part Number Description
3 606625 PCM bracket bolts (2 required)
4 031400 PCM and bracket
Removal and Installation

  1. Disconnect the battery ground cable. For additional information, refer to Section 414-01 .
  1. Remove the cabin air filter plenum. For additional information, refer to Section 412-01 .
  1. Remove the glove compartment.
  1. Disconnect the 3 powertrain control module (PCM) electrical connectors.
    • To install, tighten to 5 Nm (44 lb-in).
  1. Remove the 2 PCM nuts.
    • To install, tighten to 8 Nm (71 lb-in).
  1. Remove the 2 PCM bracket bolts.
    • To install, tighten to 7 Nm (62 lb-in).
  1. Remove the PCM and bracket as an assembly through the glove compartment opening.
  1. To install, reverse the removal procedure.
Don't get a used PCM, have yours tested and repaired. Otherwise, your car won't start due to the PATS if you change to another PCM. You need the right tools to reset the security.
 
Well I went out to move my car today aaaaaannnnnnd guess who's car is broken....



Still seem like a computer issue? Definetly seems like one....but again no check lights or anything
 
Well I went out to move my car today aaaaaannnnnnd guess who's car is broken....



Still seem like a computer issue? Definetly seems like one....but again no check lights or anything

Something isn't sending the right signals to the engine...the idle is all over the place...this COULD be multiple issues or it may be simply the PCM isn't communicating correctly ...I would suggest hooking the car up to a monitor/ computer and see if your engine is running (RICH) or (LEAN) you could see if there is a air leak somewhere
 
Update! Its an update! I know you guys have been on pins and needles anxiously waiting for this! It is still broken! (obviously)

for the past few times i have started the car, it has been taking longer to crank over, whereas before it would start right up without hesitation

Okay, so I started it (took a little longer than normal) and it ran normally (which means it ran terribly), but it didn't really do its revving thing. I watched the throttle position and that is not the problem here. At first the system ran lean/normalish, but it became more and more rich until it died. It seems like there is a correlation between how throaty the system sounds and lean/rich it is. When it is lean it sounds more like a dying cat. When it is rich is sounds like a deep, throaty um...jaguar/lincoln abomination thing.



First vid i took. Took a bit longer than normal to start (a teeny bit longer than last time). Notice that when the car falters/stalls the Load_PCT% decreases
I scrolled to the last menu so you can see the Throttle Position (TP) and the Oxygen Sensors indicating whether system is lean/rich.
(sorry it is sideways)



Second vid. When u put key in "on" position the car went nuts. the security light was blinking like crazy, and the car kept bonging putting out the same error message.... "literally everything that could possibly be go wrong with me is going wrong with me so just please don't try to start me and just take the key out the ignition and just go away." Took waaaaay way way longer to start. hesitated a lot, and thought it wouldn't even turn over. but it did, but after it did it very near immediately died (watch revvs).

DEFINITELY seems like a computer issue now..
 

rofl...yes. BUT I recently just got a whole bunch of help from other people, and they suggested all sorts of things.
1. key isnt recognized. i can fix this for free, so am going to do that tomorrow
2. too far advanced/retarded timing

what are your thoughts?
they also said an ultra advanced (dealer-level) scan tool would help. but that would require going to the dealer....and I am fairly certain it is the pcm. then again I was fairly certain that everything else I have done to this car would fix it...
 
The revving by itself says it's the PCM (applies to 2nd gen LS).
 
rofl...yes. BUT I recently just got a whole bunch of help from other people, and they suggested all sorts of things.
1. key isnt recognized. i can fix this for free, so am going to do that tomorrow
2. too far advanced/retarded timing

what are your thoughts?
they also said an ultra advanced (dealer-level) scan tool would help. but that would require going to the dealer....and I am fairly certain it is the pcm. then again I was fairly certain that everything else I have done to this car would fix it...
"Usually a bad or failing idle control valve will produce a few symptoms that can alert the driver of a potential issue.
  • Irregular idle speed. One of the most common symptoms commonly associated with a problematic idle air control valve is irregular idle speed. ...
  • Check Engine Light comes on. ...
  • Engine stalling." Maybe your IAC Valve is messed up...I would try putting a 5 AMP fuse in your engine compartment power distribution box slot # 10 and see if this helps the problem or you could check the valve and see if its malfunctioning...
 
"Usually a bad or failing idle control valve will produce a few symptoms that can alert the driver of a potential issue.
  • Irregular idle speed. One of the most common symptoms commonly associated with a problematic idle air control valve is irregular idle speed. ...
  • Check Engine Light comes on. ...
  • Engine stalling." Maybe your IAC Valve is messed up...I would try putting a 5 AMP fuse in your engine compartment power distribution box slot # 10 and see if this helps the problem or you could check the valve and see if its malfunctioning...

This is bad advice to lead him back in the wrong direction! His 2nd gen LS does not have an idle control valve. It has electronic throttle control, which produces different symptoms for certain problems, than an engine without ETC would. This is one of those cases.
 
This is bad advice to lead him back in the wrong direction! His 2nd gen LS does not have an idle control valve. It has electronic throttle control, which produces different symptoms for certain problems, than an engine without ETC would. This is one of those cases.
Correction I was at work when posting .....A messed up PCM is very POSSIBLE if you read my first post I said it could be a PCM issue but by the sound of the engine and the car running lean at beginning towards beginning of idle seems to be wanting air and it seems like the richness at end the car is wanting fuel...hence fuel to air ratio is way off when
 
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At this point I would certainly start replacement of the PCM and retest. Gotta start somewhere.. let us know the results
 
Yes okay, so I just went out and now the car doesn't even start. The first attempt got me 5 cranks before it quit. Then I tried again and barely got 3 turns before the car alarm went off. (1st heart attack) after the alarm quit, I opened door and the triggered the alarm again (2nd heart attack) now anytime you open a door/trunk/hood, the alarm goes off. The only way to stop this is to start the car....(in case you weren't paying attention, the car doesn't start)
 
While the alarm was going off, the parking brake light (the one next to the button, not the one in the dash) was blinking in sync with it. nothing else was doing this, just the parking brake light.
 
While the alarm was going off, the parking brake light (the one next to the button, not the one in the dash) was blinking in sync with it. nothing else was doing this, just the parking brake light.
Press and hold the RESET and SETUP Button then turn the key to the on position so the lights on dash are illuminated...don't turn key far enough to crank just to on position...press and hold the reset and setup buttons on Message Center ....where the fuel specifications show up there should be some PCM info can you tell me what it says?
 

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