92 PA stuttering while driving

[josh8966]

Hey guys,

I have an unusual problem with my 92 pa and you guys on this forum have helped me more then any other resource in the past so here's my latest problem. For the record its milage is 78,XXX and its had the following replaced recently:

Ignition module
Ignition coil pack
spark wires+plugs
Oil pressure sensor

Basically, while driving the car will start to stutter and fight to stay running. Giving it more gas doesn't seem to help. It started 3 weeks ago one day when the car suddenly shut off. Started right back up fine and ran about 2 weeks with no problem. The other day it started doing it while driving and I gave it some gas and it went away (service engine light came on but I turned off. I scanned it with a computer and nothing.) That time the car ran normal after the incident.

Today, on the highway, it started stuttering a little more violent and lost most of its acceleration. I pulled over and put it in park, gave it some gas, still stuttering. Turned the car off then back on (after about 10 seconds) and it started fine and ran fine.

So far the thoughts are it might be a bad fuel filter backing up. My next fear is its the fuel pump going bad or the PCM. It seems like a fuel problem and not an electrical one since I've already replaced the coils, module, and plugs and wires.

Would a bad sensor leave a computer code?

Anyone have any thoughts on what it could be?

Thanks,
Josh A

[maxwedge]

You turned off the cel,or you had no codes then cleared it? I would check the fuel pressure when this occurs, if ok, this could be caused by an intermittent crank sensor.

[big white bufflo]

what i know of that year is on crank sensor unless the light is on no code is stored once you turn of the key it clears the code some symtoms of crank sensor are the car will like hicup or buck then run smooth or will not start have you checked fuel pressure that will tell you if pump is on the way out

[josh8966]

Haven't checked the fuel pressure but thats the next step.

Replaced the fuel filter and the problem persists. Today I was driving for about 15 mins, pulled over and idled for about 2 mins, then it started to "hickup." Service engine soon light came on for literally a split second and giving it gas helped somewhat though it continued to run rough as it lurched forward.

So, would a bad fuel pressure regulator or a bad injector act like this?

Not looking forward to replacing the fuel pump, hopefully the pressure is good.

[maxwedge]

As part of normal diagnosis you need to check the FP. Then you move on to ign issues, ie: maf or ckps.

[Mickey#1]

92 ignition modules ground through the mounting bracket. Make sure the top of the mounting bracket & both sides of the mounting plate are corrosion free. I like to smear a little dielectric grease on those surfaces to help prevent future corrosion.

I'd also check the battery cables for corrosion. You need to remove the rubber boots to clean them properly. Use some dielectric grease on these also. This is a common cause of problems on these cars.

You can try running with the MAF unplugged & see if it runs better.

Check the vacuum line that goes to the fuel pressure regulator for any signs of fuel. If found then replace.

[josh8966]

After digging around through past posts I'm starting to lean toward a bad crankshaft sensor.

Would a bad sensor make my tachometer bounce around randomly? Mine has been doing this very regularly since my stuttering problem began.

Going to have a mechanic friend replace it this weekend.

[Morxano]

I had the EXACT same problem with my '94 PAU.

The problem? The EGR tube had broken off inside the engine. Replaced this bad boy and cured it right up. Of course finding the replacement was a nightmare... if you don't have the ultra model should be about ten bucks at a pick and pull.

[josh8966]

Originally Posted by Morxano

I had the EXACT same problem with my '94 PAU.

The problem? The EGR tube had broken off inside the engine. Replaced this bad boy and cured it right up. Of course finding the replacement was a nightmare... if you don't have the ultra model should be about ten bucks at a pick and pull.

Whats an EGR tube and what problem did you have? The stuttering or the jumping tacho?

[Morxano]

Started with the stuttering, progressed to shaking, rough running etc. Eventually, its just going to start shutting everything off on you.

Its the little tube that comes out of the front right side of your engine (as you're looking at it with the hood popped) Of course, it might just have a crack in it too. Spray some wd40 on it with the engine running, if it sucks it up, thats where your problem is.

[josh8966]

So I got a service engine soon light the other day when the problem occurred while driving.

I plugged in a reader and got a code 42 which is one of three things:
1)Electronic spark timing circuit open or shorted ground during engine run
2)Direct ignition system fault - bypass circuit open or shorted ground during engine run
3)Fuel cutoff relay circuit- open or shorted ground during engine run

Can anyone explain what this means and which problem is most likely going on?

thanks,
Josh A

[Donb1955]

I have a 95 PA Ultra with the same problem. I have replaced the
crankshaft sensor. While doing so I found that the camshaft sensor
leads had melted through the outer coating causing a short.
Replaced the leads, connector and the sensor. Got it all back together
and it didn't change a thing. I checked the fuel pressure and found
it to be 2 psi below the minimum. I don't want to pull the tank either
so I am checking everything else possible that could contribute. The
looks good, I put a noid lihgt on it to check the signal to the
injectors. Checked the spark plug wires, the coils and replaced the
ignition module. I'm running out of things to check and getting very
frustrated. I actually let it set for several months now before
getting back into it today. I plan to sell it one way or another but
it has gotten me hooked. Please let us know if you find the problem!
Don

[Donb1955]

I have a 95 PA Ultra with the same problem. I have replaced the
crankshaft sensor. While doing so I found that the camshaft sensor
leads had melted through the outer coating causing a short.
Replaced the leads, connector and the sensor. Got it all back together
and it didn't change a thing. I checked the fuel pressure and found
it to be 2 psi below the minimum. I don't want to pull the tank either
so I am checking everything else possible that could contribute. The
EGR valve checks good, I put a noid lihgt on the injector leads to check the signal to the injectors. Checked the spark plug wires, the coils and replaced the ignition module. I'm running out of things to check and getting very frustrated. I actually let it set for several months now before
getting back into it today. I plan to sell it one way or another but
it has gotten me hooked. Please let us know if you find the problem with your's!
Thanks, Don