Blinking CEL

[94_XLT]

I could not find anything on the 1st gen Explorer's so I wanted to make sure this is the same story....My CEL is now blinking. over the past two months its been driven a whole 6 or so miles. It ran fine last time. I went to start it up to let it use up some of the old gas and the CEL started blinking. Do I have a miss? It didn't seem to idle rough for the 10 seconds or so i had it running before i noticed the CEL. I did blip the throttle before I saw the CEL come on too. What should I do to try and fix it.

 

[MrShorty]

1st step would be to pull the codes from the computer and see what the computer has to report. You can get a cheap code reader if you want, or simply use a paper clip/jumper wire and count the flashes of the CEL (instructions for this sort of test are in the stickies in the EEC-IV forum).

 

[94_XLT]

Sorry for the delayed responce...I tried pulling codes with the KOEO way and i only get 111....any idea whats wrong...the CEL only tells me everything is ok

 

[MrShorty]

Do you get 111 from the KOEr test as well?

If you really are only getting pass codes from the computer, then we'll just have to start guessing. Any other symptoms when the CEL is flashing? You might check fuel pressure. You also might try running the engine a little longer to see if it just needs to see the fault longer before it stores the code.

 

[94_XLT]

Honestly It worry's me to run it because it runs smooth for about 10 seconds then it dies out for 1/2 a second to a second then runs again. CEL will blink 3 times then the engine will stall then come back...

I thought I also smelt gas when I killed it.

 

[MrShorty]

The smell of gas could indicate that it's running rich, or that it's misfiring.

Exactly what do you mean by

it dies out for 1/2 a second to a second then runs again.

This makes me think of an intermittent electrical fault that causes the engine to "stall" briefly, then start back up. I might look at the main PCM power and ground circuits to see if they look ok (PCM power and ground sometimes "pigtail" directly off of the battery cable, and after sitting may have corroded). I might also check the CKP circuit.

 

[94_XLT]

Well at the start of the thread I said I thought it was misfiring. Now since the CEL is giving me 111 would that mean the distributor is gone?

One other thing...the day before it started misfiring there was a rainstorm.

 

[MrShorty]

4.0 is a distributerless engine: you have coil packs -- no distributor.

A bad coil pack (or other ignition fault) could certainly cause a misfire, and I could easily see you PCM missing the misfire condition. In addition to the other suggestions, you might try running the built in cylinder balance test (see instructions in the EEC-IV forum) to see if the PCM can see a misfire.

 

[94_XLT]

I searchsed around and could not find it...and yeah the computer is catching the misfire...least i think thats what the blinking stands for...

 

[rayford2]

CEL Blinky

Define "blinking CEL" for us. Does the CEL stay on for any length of time and then go off? Or is it constantly flashing on and off, in which case I would suspect an intermittent wire or connection in the dash, especially since there is no trouble code stored.
Also please be aware that if you remove that jumper wire between the test connectors at any time during an on-going test, you have just reset your computer fault codes to 111. Now you have to drive around some more to reestablish the fault(s) into memory before you can read them again.
Please keep us posted on this matter......Ray S. in PA

 

[94_XLT]

Never pulled the jumper while running it. I run the car for about 10 seconds then kill it usually....blinking stays constant. My guess is a wire shorting out or the ignision coils

 

[MrShorty]

I searchsed around and could not find it...and yeah the computer is catching the misfire...least i think thats what the blinking stands for...

If you run the cylinder balance test, it should report which cylinder(s) it detected the misfire on. I included the basic test protocol for the cylinder balance test in my "notes on pulling EEC-IV codes" thread in the EEC-IV forum.

 

[94_XLT]

well honestly I do not want to run the truck for long...It will not come out of diagnostic's mode...the CEL blinks 3 times now and then the engine cuts for like 1/2 a second...I recorded a video to show what I mean Also my idle is almost 2000 RPM. Any clue about that

http://www.youtube.com/watch?v=wAmF2j0G1Xw

Sorry for the quality. Its off my blackberry

 

[94_XLT]

bump...any ideas?

edit: by the way I changed the wires and almost no difference.... if anything

 

[MrShorty]

I'm having trouble with the video, so my comments don't reflect what the video shows.

It will not come out of diagnostic's mode.

A blinking CEL would certainly be consistent with something stuck in diagnostic mode (as the CEL blinks to output the codes). I don't think I've ever heard of a case where it was stuck in diag mode -- the only thing I can think of that would get it stuck in diag mode would be a wiring fault in the STI circuit. Part of the KOER test is high speed test, which cold explain the high idle. If you've communicated this correctly, maybe the fact that it won't come out of diag mode is the whole problem.

Also my idle is almost 2000 RPM.

Beyond the previous, the usual 1st thing to check when you have a high idle is to make certain there are no vacuum leaks.

 

[94_XLT]

would taking the neg side of the battery off for 15ish minutes kick it out of diagnostic mode? and I think something is still wrong cause if you get the video to work...it runs...and then dies for 1/2 a second and comes right back on. and ill look for vacuum leaks today...where should I look for them though? XD

 

[94_XLT]

The smell of gas could indicate that it's running rich, or that it's misfiring.

Exactly what do you mean by This makes me think of an intermittent electrical fault that causes the engine to "stall" briefly, then start back up. I might look at the main PCM power and ground circuits to see if they look ok (PCM power and ground sometimes "pigtail" directly off of the battery cable, and after sitting may have corroded). I might also check the CKP circuit.

sorry for the double post but i compleatly missed this. Where is the CKP circuit?

 

[MrShorty]

would taking the neg side of the battery off for 15ish minutes kick it out of diagnostic mode?

I suppose if the problem was a software/firmware glitch maybe. (though I haven't heard of this being the case before). The PCM goes into dagnostic mode when STI (self-test input, the single wire associated with the self-test connector) is grounded, so I was envisioning some kind of short to ground in the STI circuit. Disconnecting the battery cable wouldn't fix this kind of short to ground.

and ill look for vacuum leaks today...where should I look for them though?

Anywhere you find vacuum lines. I'd probably start at the octopus towards the rear of the upper intake.

Where is the CKP circuit?

CKP (CranKshaft Position) sensor is bolted to the front of the engine near the harmonic balancer/belt pulley. The CKP is a basic Hall effect sensor that is wired in to the ICM (ignition control module) which then sends the signal on to the PCM.

 

[94_XLT]

ok so a bud of mine come over and stole my truck...came back 5 minutes later saying "what the **** is wrong with it?" I took it out and it ran perfect...i dont know what happened but changing the spark wires fixed it. thanks for helping