Error codes 185, 186, 187...?

[NeverSummer]

I've searched all over the place and found a couple of people that have had the same codes pop up but none of them post what the fix was. As of right now the P.O.S. won't start, it sounds like it really really wants to. The car is a 92 explorer 2wd 4.0L auto. A few months ago I replaced the fuel pump, has run ok since, sometimes it takes a few more cranks to start but it starts. Until yesterday it started to run really sluggish, wanting to die. Then this morning I went to start it to see what the problem is but it wouldn't start. The only codes I am getting are 185, 186, and 187.

I pulled the MAF and cleaned it according to the procedures on this forum, no change. I unplugged the MAF and tried to start it, no change. I reset the codes and tried both, no change.

Any ideas...? how do I check to see that the FPR is working? If I disconnect the fuel line from the FPR and try to start it should fuel come out or not? Is there a way to test the MAF without the vehicle running? What else should I check?

 

[MrShorty]

how do I check to see that the FPR is working?

Fuel pressure gauge.
See the "fuel pressure test" mini diary in Under the hood.

If I disconnect the fuel line from the FPR and try to start it should fuel come out or not?

It should, but it will only be a meaningful test if you know what the pressure is in the fuel rail.

Is there a way to test the MAF without the vehicle running?

Probably not thoroughly, but you will want to get a "baseline" signal from the MAF with the engine off. Recognize, too, that, though the code descriptions for these mention the MAF, these codes really mean that the PCM is seeing something wrong with the computed air/fuel mixture, so any number of other things could be contributing to the codes: O2 sensor, vacuum leak, fuel delivery, exhaust leak, and so on.

What else should I check?

I assume those codes were all CM. Can I assume it passed (111) KOEO? Have you tried the KOER test? If you clear CM, test drive, and pull codes again, do you get the same set of codes? (See my "notes on pulling EEC-IV codes if you are unfamiliar with KOEO, KEOR, and CM codes).
These sensors usually don't cause no starts. Sometimes the MAF seems involved in no starts. For the no start, I might be inclined to believe it is a fuel delivery problem.

 

[NeverSummer]

Yes these codes are KOEO. I can not get it to start so I can not get any KOER. I reset the codes and it passed (111). Tomorrow morning I will check for vacuum leaks and fuel pressure. Will post in the morning...

 

[NeverSummer]

no vacuum leaks. it is a fuel problem, I sprayed some either in the air cleaner and it started, up ran until I didn't spray any either anymore. I disconnected the fuel line and ran the fuel pump fuel came out (not very fast though) I don't have the right fitting to connect my fuel pressure gauge to it so I don't know what the fuel pressure is. I am going to the auto parts store to get the fitting to connect it to the schrader valve on the fuel rail.

 

[NeverSummer]

I saw somewhere on here that you can test to see if your fuel pressure regulator is working by disconnecting the vacuum line. I did this and I finally got it to start, I kept my finger over the vacuum line to make sure it was running with correct vacuum. Does this mean me FPR needs to be replaced?

 

[NeverSummer]

scratch that didn't fix it....can I get a little help here?

 

[NeverSummer]

so I'm pretty sure I have narrowed it down to something with the injectors. I'm getting more than enough fuel to the rail, just not getting any fuel through the injectors.

 

[MrShorty]

I saw somewhere on here that you can test to see if your fuel pressure regulator is working by disconnecting the vacuum line.

This is a good, quick way to see if the diaphragm in the FPR has ruptured. If you disconnect the vacuum line and find gasoline there, then the FPR needs to be replaced. If there's no gasoline, the FPR diaphragm is probably still ok and you would need a pressure gauge to further test the FPR.

so I'm pretty sure I have narrowed it down to something with the injectors. I'm getting more than enough fuel to the rail, just not getting any fuel through the injectors.

Assuming sufficient pressure at the rail, are the injectors opening? This can usually be checked easily enough by simply listening to the injectors (a stethoscope type object can be useful for this) as they make an audible click when they fire. Or you can use a Noid light or similar to see if there is an electrical signal being sent for the injector to open.

 

[NeverSummer]

so the pressure is good at the rail, I checked the injectors with a mechanics stethoscope and could hear them opening. for what ever reason (I didn't change anything) it is running fine now. Did a KOER test and came up with no codes. The only issue I notice now is that it is sluggish at WOT. One of the times I tested WOT the RPMs would not go higher than 3k until I feathered the throttle a little.

 

[NeverSummer]

so it idles fine but has absolutely no power off idle

 

[MrShorty]

Is the fuel pressure staying up where it should under load?

Even though ignition timing isn't adjustable, it might be worth the effort to verify that base timing is 10 BTDC and timing advance is 30 BTDC.

The injectors might need a good cleaning.

Sometimes, a lot can be learned from the condition of the spark plugs. Do they look fouled?

 

[NeverSummer]

It again died and would not start. After trying to start it a few times, I disconnected the vacuum line to the FPR and it started right up. So, I changed the FPR. It is running a lot smoother but it still wants to die/bogs down at WOT. For now I think I can limp it home, when I get there I will check the fuel pressure under load, check timing, and check the spark plugs again. I noticed today while working on it (looking through the throttle body) that there was a small pool of what looked like oil in the back of the plenum and a good amount collected on the sides, how could it get in there? checked the PCV, was working fine, cleaned it anyway.

 

[NeverSummer]

if anyone is wondering, it was the fuel pump that I just changed 2 months ago.

 

[MrShorty]

Glad you figured out, sorry to hear that it was something that shouldn't have failed.

Since diagnosis is most of the battle, would you care to share how you determined that the new fuel pump was at fault?

 

[NeverSummer]

I tested every sensor in the engine, there was some rhyme and reason to the order. The first time I tested the fuel pressure it was fine but the car was also running fine (no codes). I then listened to the injectors with a mechanics stethoscope, they were all opening fine. I changed the FPR because the few times it would stop running I disconnected the vacuum line to the FPR, plugging the other end, and the car would start up almost instantly. After changing the FPR it started and ran good, not perfect but good. After your post I decided to check the timing just to be sure that it didn't need timing chain repair. I was very happy (and frustrated) to find out that the timing was dead on. I figured just for s#!ts and giggles I would put the fuel pressure tester on and leave it on while I drove it around for a couple of days until it started to run like crap again. Luckily I didn't have to leave it on for too long, the next day it started to run like crap again. I immediately checked the fuel pressure gauge which read about 6psi. Next step was to put the gauge on the output end of the fuel filter, still 6psi. Next up the line was the fuel pump outlet, 6psi. Which meant it's time to take the tank out, again. After I changed it it started right up and ran like a champ.

I have been thinking about this whole thing and have one question left maybe someone here can answer it for me. I know that it is completely possible that I bought a "Friday" or a "Monday" pump, but if the FPR was in fact broke could it cause the fuel pump to have to pump more fuel to keep pressure up and thereby causing the pump to wear out prematurely?

 

[MrShorty]

Thanks for sharing that.

The main way I could see the FPR contributing to a fuel pump failure is if the FPR is stuck closed. This would cause the pump to be operating at a much higher pressure than intended.