Well that could definitely do it! Keep us posted!

 

No luck...until yesterday. I switched my AC selector **** from AC to heat. Instantly I heard the unmistakable hissing of a vacuum leak coming from the selector itself. The sound seemed to go away when I turned it back to AC or to "off". I took my dash apart today to find that it was leaking from the actual switch, not the lines behind it. I also found that it was always leaking but I could not hear it installed in the dash. Apparently I've had a vacuum leak in my dashboard this entire time. I'm going to replace it tomorrow with any luck and see if it helps. BTW, my truck idled MUCH better when the **** was switched to off. The setting that leaked the least...I might be onto something. I'll keep you posted.

 

Got a new switch that doesn't leak. Instantly it ran and idled much smoother. It still has a misfire at idle though, although not nearly as bad. The rich exhaust smell has diminished substantially as well. I reset my codes and drove around for a while without tripping any, but it was just one trip. I'll keep you posted.

 

Mmmk...it's still much better, but it still runs rough right after start-up after it has been sitting for about an hour. After it warms up a little (and always at speed) it runs fine. When I come to a stop it idles prefect...for about 30 seconds. Then it begins to misfire and slowly does more and more until it's a stammering mess all over again. Question...how much play should the distributor have?

 

This sounds exactly like what my own truck was doing when my distributer pickup coil went bad on my 2000. I had a similar issue as well on my 01 when a small washer from the distributer cap attached itself to the coil.

You can OHM it out to test it. I believe that a steady reading between 500 and 1500 ohms is the acceptable range for the 4.3 but you may wish to check your Chilton manual to be certain of the values.

Other possibilities that I can think of are a bad MAP sensor or coolant and or air temp sensors that are giving incorrect readings.
I would say a possible bad Mass Airflow sensor as well but I'm pretty sure that a 95 doesn't have one.

You can test the MAP sensor as follows.


Inspect the rubber nipple (fitting) from the MAP sensor to the throttle body. Repair as necessary. CAUTION: When testing the MAP sensor, be sure that the harness wires are not damaged by the test meter probes.

Test the MAP sensor output voltage at the MAP sensor connector terminal B. With the ignition switch ON, and the engine OFF. Output voltage should be 4 to 5 volts.

Test the MAP sensor output voltage at the MAP sensor connector terminal B at a hot, neutral idle speed condition. The voltage should drop to 1.5 to 2.1 volts.

Test MAP sensor supply voltage at sensor connector terminal C with the ignition ON. The voltage should be approximately 5 volts.

Good luck and let us know how it goes.

 

Wow, thanks for all the info...Now to find someone with the tools and know-how to test all this stuff. (electricity and I do not agree with one-another) You are correct about no MAF sensor on the 95 BTW.

I have this feeling I'm going to be searching for how-to's on swapping the Distributor.

 

It's getting worse...sputtering under light throttle almost always. Still ok at speed...Distributor? I've only got the cash to take one more swing at this one lol.

 

you dont have to spend money to check your distributor. first take the cap and rotor off and then grab the reluctor (rotor base) and turn it left and right. you shouldnt have more than 1/32" to 1/16" of play. then pull the whole distrbutor out and physically lookl at the lower gear and look to seeing if the bushing in the dist housing have and play. also chech to see if the reluctor ( black colored rotor base plate) has slipped on the center shaft. if it has it will retard your timing like it did on mine....however you would have to have a good dist to check to see how much it slipped. if it did then you would have to press it off and repress it back on in the right postion if yor capable of doing this or use a machine shop. or you can replace the entire distributor. but like Kyle said i would do a leak dowwn test of the fuel pressure first...

 

bigdaddykane93 is correct, you don't have to spend money to test any of these parts. For the electrical portions that I mentioned in my last post you only need a cheap volt and OHM meter available at any radio shack type place for about 10 bucks.

They can also be replaced separately if something tests bad so you don't need to purchase a whole distributer. The individual parts are rather inexpensive as well as long as you don't try to buy the performance parts that they show on the autozone website.

There are not many parts on these trucks that you can't test first to see it it is in fact the problem before you throw any more money at it with new parts that may not be bad.

 

Cool, thanks fellas.