Patt, no he probably doesn't have EGR. It would be the canister purge solenoid.

 

I'll be performing another compression test this afternoon. I'll be sure to post the updated results.

 

I wasn't 100%..rock had the parts for his engine so based it off that..

 

From what I've been reading, some years use EGR and some do not. I bet adding an EGR is feasible considering the extra vacuum ports on the keg. It is not something I have any plan on doing.

Here are my exact steps for yesterday's compression test:
- Remove air filter tube / housing
- Remove plug wires (including coil - all were labeled)
- Blow debris out of (and around) heat shields
- Remove plugs
- Remove fuel pump fuse
- Remove injector connectors
- WOT, three cranks / cylinder

Each cylinder was tested dry / wet with the engine near operating temperature, roughly 155 / 160 PSI in each cylinder. I didn't even bother recording the numbers because they were all spot on.

As some of you may recall, cylinder three has been a constant problem. The plug looked a little wet in comparison to the other five. I hooked everything back together and put three's plug into one's cylinder, same codes from the PCM (neg terminal was removed). I also switched one and three's wire, no change. To make sure it was sparking, I pulled the plug at idle and held it near the frame and could clearly see and hear the spark. I checked all other wires / plugs as well.

Pulling three's injector power seems to have zero effect on the idle speed, in contrast to pulling any others. I don't remember cylinder four making much of a difference either. I'm wondering if this may be because three and four are both middle cylinders? All injectors are receiving power. The injectors themselves are also new, albeit re-manufactured.

Before I left Autozone, I pulled the plug on the MAP sensor. I stalled not three minutes after. Based on that, I'm assuming the MAP sensor is doing its job.

Pulling on the harness also has zero effect.

I'm wondering if three's injector is receiving power, just not enough? I'm going to try to get a reading on it later today. It had no problem illuminating the 12v lamp I was using, nor did any of the other connectors. If I can't get a reading (due to the pulsation), I'm going to replace three's entire length of wire hoping for a difference.

If all else fails, I'll try rotating the distributor to advance the fuel sync.

 

That's correct msheridan. 1996 didn't unless they were California/Federal HD emmisions compliant. 1/2 tons didnt for 1996. Don't replace the whole wire... What size injectors do you have on it?

 

GB Remanufacturing #812-11126

I'm not exactly sure on the size.

 

msheridan you got the wrong injectors just like me. Those are for a 1992-1993 Chrysler Imperial 3.8L V6, and they won't work on your truck no matter what. Give me a few minutes and I will get you a link to the RIGHT injectors. Wrong injectors will do just what you are experiencing. They are either giving too much fuel or to little, which will cause misfire. Most likely it is too little. Those injectors were designed for a smaller lower compression engine, so chances are that PCM has fuel sync messed up to compensate (which put the right injectors in and it will correct itself) and the PCM also most likely has the injector signal band open/closed as far as it can to help compensate as well. So it misfires, and the misfire symptoms you are experiencing are exactly what I had... I also had the wrong injectors and nearly had to have the truck towed.

 

Also RockAuto and my other parts catalogs show that as being the correct injector but it isn't... So I am checking that out... It is the wrong rating.

 

Those injectors that you have are 21.8 lb/hr injectors...

 

http://www.summitracing.com/parts/smp-fj716/overview/ Those are the right ones far as I can tell.. Any other DF guys on this?