On my 95 I just had the fuel injector, fuel pump and gas tank(new gas in it) replaced by a reputable guy. He said everything checks ok. My truck- when running surges (idle) high/low.Even when I'm stopped at a light, then it'll stall. Now it's stalling out whenever I'm stopped. It even stalls if I'm cutting the wheel to make a turn. In a straight line it runs great, lots of power. It sets no trouble codes at all. The check engine light does work. I just tuned it up. All what was wrong were the plugs were a little fouled because it would idle for long periods of time. This truck has sat for about 2 1/2 years. It would get started every once in awhile during that period, but not very often. Funny thing is, I live in NJ and we do emissions here and passed with no problems. I've never changed the O2 sensors ,tps, iac, or any other sensor since I've owned it(about 7-8yrs). Wouldn't it throw a code if a sesor went bad? Before it was parked this thing ran like a champ with no problems at all! It has 193,000 miles on it, but the original owner replaced the motor with a brand new Jasper engine. I bought it around 144,000.
This truck almost got me killed tonight trying to cross an intersection! Would anyone have any clue on what might be wrong or what should I check/replace? I really love this truck but I'm getting so frustrated with it!
Thanks for any and all replies.

 

1995 has two different types of injection systems. Which engine do you have?

If the engine look like this you have CMFI:





If it looks like this you have CSFI:

 

I have the CMFI(top pic).

 

Could be a leaky fuel pressure regulator or "nut kit", (lines inside plenum) very common problem. Check fuel pressure and leakdown. Most auto parts stores rent and/or sell fuel pressure testers. Quick and easy test to determine if there is a leak somewhere. Ignition in RUN position, engine OFF, fuel pump running, pressure must be 55psi to 61psi and must remain above 50psi for 10 minutes after the pump shuts off. Check it a couple of times with both a cold and warm engine, and post your results.

 

Wouldn't it make sense for the mechanic to check the fuel pressure since he worked on the fuel system? Since he had it apart it would've made alot of sense. Could you tell that the regulator is leaking just by looking at it? He told me my old fuel pump was bad because it was low on pressure, so that's what tells me he tested it.

 

Absolutely you check the fuel pressure any time you work on fuel delivery! The regulator and/or lines can and do leak. In the early stages it can be difficult to visually detect, that's why you always check fuel pressure AND leakdown. If there's a leak, it will show up on a leakdown test. Provided he is aware of the test, the amount of allowable leakdown, knows how to do the test, and actually does it.... only HE knows the answer to that.

 

If it isn't the regulator, would it be possible to be a bad sensor? But....if it is, wouldn't it give a trouble code? Think maybe it might be a bad O2 sensor? I've owned this truck and I've never had to change a sensor, so that's a little suspect also.

 

If any of the sensors are bad, or circuit for a sensor, it will set a DTC. It is possible for an oxygen sensor to be "lazy" and not set a DTC though. Check fuel pressure and leakdown first. Very common to have problems in the plenum and it's quick, cheap, and easy to test.

 

Spoke to the mechanic and I told him the issues I'm having. He said everything has been changed that would affect those problems. He said something might have to be adjusted so it won't stall out, he said something about the tps--which I didn't know could be adjusted. I'll let you know how it turns out.

 

Simple to check it yourself for leakdown.
Check your receipt, see if it lists the injector, regulator and nut kit, (lines).