What are the chances my MIL is burnt out?

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rubydist

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I disagree with one part of your statement above - I do not think that you have ruled out the fuel pump check valve.

As I understand your results, if you cycle the key on/off several times, the fuel pump builds pressure and it stays up (at least for a while). But overnight, there is a good possibility that the fuel pressure has dropped significantly. If I understand that correctly, then in my experience it IS the fuel pump check valve that is at least part of the culprit for your loss of pressure.
 

Greg Corcoran

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And of course the tach was dead and check engine light was on.
I managed to lose my OBDI code printout, so I was just on wikisho to get it again, and I noticed there is no hard code for CID malfunction or missing signal - So why was my MIL on the entire time my CID was unplugged? I'll pull codes tonight when I get home, but with the CID unplug yesterday I'm not sure codes will be particularly instructive now? Previously, like 2 weeks ago, I had 111 and 111 for KOEO.
Since this bucking only happens the first few minutes/miles the car is on from a cold start should I be looking at other open loop gremlins? Dirty MAF, sticking IAC, something else? I found a stash of my '92 SHO leftover parts this weekend (anybody need a complete '95 brake upgrade?) including a large bore MAF, and a set of used injectors. I was thinking of swapping the MAF and resetting the computer, but I'm beginning to feel like I'm just flailing without purpose.
I think I forgot to mention I changed the fuel filter and HEGOs this weekend when I had the car up on the lift for an oil change. Both items were Ford factory originals. Rear HEGO was loose, almost finger tight. I was hoping that might have been it, like intermittent ground until everything got hot and sealed better, but apparently not.
 

Greg Corcoran

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But overnight, there is a good possibility that the fuel pressure has dropped significantly. If I understand that correctly, then in my experience it IS the fuel pump check valve that is at least part of the culprit for your loss of pressure.
Rubydist, Yes I have one data point (overnight last night) where the pressure dropped from 38 to 36 in about an hour then from 36 to 7 in about 3 hours. Kinda follows the cooling of the engine bay? But the pressure also rises on each key on, stepwise, prior to starting engine which I thought earlier in this thread you or Zoomlater said exonerated the check valve? I will get another pressure decay data point tonight.
If it is a check valve responsible for the hard starts, that would not be the cause for my surging at 3000 rpm with cold engine? If it is valve I'm back to two distinct culprits. Leaky/sticky injectors or bad fuel pressure regulator would be a single failure point responsible for both issues? Is there a "rule of thumb" for how long the check valve is expected to hold pressure? I thought valve was to prevent vapor lock, so a couple hours would be sufficient, it wouldn't need to hold pressure for day or more?
 

luigisho

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then what is code 214? The check engine light should come on whenever a major component or sensor failure happens. Some small exceptions but major failure should trigger a code in some system
 

Greg Corcoran

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then what is code 214? The check engine light should come on whenever a major component or sensor failure happens.
Hi Luigi,
I'm going by the OBD I code guide on wikisho. 214 will be a stored code, but it does not turn on the check engine light while you are driving like a Lean O2 sensor or out of range coolant temp if I'm reading the chart properly. There are only 9 codes shown that turn on the check engine light while the car is running.
Assuming wikisho is accurate... If it's NOT accurate could one of you please post the link to a more comprehensive/correct list of 3 digit OBD I codes? Thanks.
 

Greg Corcoran

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I I'll pull codes tonight when I get home, but with the CID unplug yesterday I'm not sure codes will be particularly instructive now? Previously, like 2 weeks ago, I had 111 and 111 for KOEO.
Tonight's codes: KOEO 111; Stored 173, 214, 542; KoER 536.
So 173 is possibly from being flooded during the attempts to start the car w/ CID unplugged, or maybe pointing to location of my faulty injector(s)?
214 is expected.
542 is likely from me stalling on the way to work last week (a few steep hills on the way to work have red lights, and things happen...). I used to have this all the time on my '92 if I had stalled out recently
I presume 536/BOO is operator error during KOER?
I attempted cylinder balance test twice, and got 538 twice. Operator error? What do I need to do besides goose it after KOER sequence is complete?
Codes cleared now.
Fuel pressure 36 at rest after work. 17 psig 2.5 hours later when the code pulling commenced. I'll see what it is in the morning
I also decided to clean the MAF hot wires after thinking about open loop operation and seeing a TSB about contaminated MAF. I got a little tiny wisp of white, like maybe a fraction of a feather or dandelion seed while spraying with a can of contact cleaner. It floated away and slowly dropped to the floor but I couldn't find it again to see what it actually was.
 

Greg Corcoran

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I count ~26 R codes on my list. Not sure if they all trip the MIL
Thanks for the link. What I liked about the wikisho codes is there is a 4th category in addition to O, R, M, which is what I've referred to as "hard codes", things that trip the MIL while you are driving. There are 9 listed, and CID is not one of them.
 

luigisho

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chopped from the old sho phoenix site
KOER (Key On Engine Running)

Now, start the engine. The CEL will blink 3 times. Watch the RPM guage carefully, and when you see the RPMs rising (the computer is advancing the timing) then follow these steps: (this is so the computer know these things are working)

1. Turn the steering wheel 1/2 turn to the right and then to the left.
2. Step on the brake
3. If your car is an ATX, switch the overdrive off, then back on.


In a moment the RPMs will go back down and the check engine light will flash once. Now step on the gas for just a second (at least 1/4 way down). Now the codes will be displayed.

Clearing the Engine Codes

Generally, the best way to clear your codes is to disconnect your battery for at least 10 minutes.

Cylinder Balance Test

This is to make sure that all of your cylinders are working right. After you have run the above test, press the gas pedal down again at least 1/2 way, just for a second. The RPM guage will move and the engine will start running a little rough. This is because your computer shut one of the cylinders off. It will do this 5 more times, once for each cylinder. Then it will display the codes.


Three Digit EEC Codes (92-95 SHO)


Two Digit EEC Codes (89-91 SHO)

Cyinder Balance Codes

10 Problem with cylinder 1
20 Problem with cylinder 2
30 Problem with cylinder 3
40 Problem with cylinder 4
50 Problem with cylinder 5
60 Problem with cylinder 6
9 No Problems
 

rubydist

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Greg, the fuel pump check valve is expected to hold pressure for several days. This is because at engine cranking, the fuel pump only runs for a couple of seconds and then does not run again until the key goes to "run" (to prevent serious flooding or fire in the case of fuel line failure). Your symptoms are very typical of a bad check valve.

Of course, you could get a similar symptom from a leaking fuel injector, but I don't recall you having a hot restart problem, and a leaking fuel injector will almost always manifest itself as a flooding at hot restart situation.

The 173 (rich on right, rear bank) could be a clue on a fuel injector issue. This controller will only set fuel trims for the entire left and entire right bank, so if one of the three injectors is operating significantly different from the others, you can have issues with driveability and performance.

I would still be looking at cleaning or replacing injectors next.
 

Greg Corcoran

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Of course, you could get a similar symptom from a leaking fuel injector, but I don't recall you having a hot restart problem
Thanks Rubydist. I do have the occasional hard starts hot or cold. Just not consistently one way or the other, that's what's so odd. It's really the bucking/surging between 3000 and 4000 rpm when cold that is really annoying. That's consistent for the first few miles every cold start. The surging was greatly reduced today, present, but not whiplash inducing, so maybe the MAF cleaning did something, or the BG44K I put in last week is finally doing something? I forgot to reset the computer last night, like the MAF cleaning TSB recommended (it was late). I reset it tonight after getting home. Let's see what happens tomorrow.

I have an appointment for an injector cleaning at my local Ford store tomorrow morning. And I do have a fuel pump assembly on order through NAPA, should be here Thursday or Friday.
 

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[QUOTE
I have an appointment for an injector cleaning at my local Ford store tomorrow morning. And I do have a fuel pump assembly on order through NAPA, should be here Thursday or Friday.[/QUOTE]
So no significant improvement with an injector flush. Surge at 3000-4000 rpm, maybe a bit milder, leaving the Ford store, plus a really long crank in the lot of the dealer.
NAPA Called and the fuel pump is in. I'll pick that up tomorrow but I'm not sure when I'll get a chance to drop the tank, wife has plans for us this weekend. I'm leaning towards the pressure regulator now, if for no other reason than I can picture it being the hard start loss of pressure and bucking common source rather than the check valve having anything to do with the bucking/surging. However, I'm wondering now if I shouldn't be thinking maybe an ignition system hardware issue, Coil pack or DIS? The tach does not waiver during the bucking. Which is why I was thinking fuel...
 

Greg Corcoran

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Well what a revolting development this is.... Now hot starts are almost impossible since the injector cleaning. Cold starts are hit or miss. The oddest hot start, once it finally started after an unbelievably long crank, the car "chugged" (for want of a better term) at ~500 rpm ignored gas pedal input for about 15 - 20 seconds and kept at 500 rpm. Finally responded to pedal, then raced to 2000 rpm and slowly came back to normal idle. WTF? Cleaning the injectors ruined an injector(s)?
 
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rubydist

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has it changed any in the past couple days?
 

Greg Corcoran

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has it changed any in the past couple days?
I've only driven it a few times since Thursday. Cold starts have all been fine. Only one hot start, and it was flawless. So now I'm completely baffled. My mileage seems to be off, this tank of gas has gone really quick. I'll pull codes tomorrow and see if anything new showed up.
 

Greg Corcoran

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has it changed any in the past couple days?
FWIW - I did not get motivated to install the new fuel pump assy this weekend, it was bone numbing cold in Colorado, even in my garage. So I filled up on the way to work this morning and my mileage is up a little (22.9 mpg now vs 22.1 to 22.3 the few tanks before injector cleaning)

I pulled codes tonight 111 and 111 for KOEO. Hot starts after a few minutes are fine, cold starts are no different, or maybe a bit better. Warm starts are a bit more difficult, like if the car sits for 20 - 45 minutes it cranks noticeably longer than a hot or cold start, and then sneaks up on a smooth idle. Nothing yet as bad or weird as my post from 2/17, but definitely more difficult to start.

I tried a little experiment after seeing other posts on this and other sites about the canister purge system on EEC IV messing up cold engine performance. I disconnected and plugged the line from the purge valve to the intake and loosened the gas cap. Strange result - the initial surging on the first pull is gone, instead it feels like timing not advancing or driving into a very stiff headwind, but no surging. Then once closed loop takes over in a few miles no problems, just like always. I can probably live with that. But twice, the surging came back, just as bad, if I got a chance to get to 3000+ rpm on a second or third pull in the first mile or two... But once I've driven 2 or 3 miles and closed loop came on - no problems.
 
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rubydist

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but you cannot keep the purge line plugged - it will saturate the charcoal canister and the whole car will smell like gas.
 

Greg Corcoran

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but you cannot keep the purge line plugged - it will saturate the charcoal canister and the whole car will smell like gas.
Yeah, I know. Since it wasn't a true fix I hooked it back up already, before I got the gas smell. I was hoping the fact it changed my symptoms was a clue that would help someone better pinpoint my issue. I'm completely stumped. I'm thinking I'll follow the troubleshooting chart for canister purge in section 03-13-6 of the shop manual when I change the fuel pump. Not so much that it will fix my original problem, but something might be going on.
 
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