Well, all the grounds are good. So I am questioning the PCM. But why would it have just gone bad? Or was it going bad slowly and this work finally took its toll? Also it is regulating voltage at approx 15 volts...

 

The gauge isn't the most accurate..... 14.7 or so is good.

Check the connectors at the PCM, and follow the wiring harness to the IAC. Make sure everything is in good shape, and nothing got pinched, or routed to near the plug wires....

You replaced the IAC? What brand did you get?

 

That's both gauge and voltmeter readings HY. Connectors look all fine, didn't pinch any wires, all of the things it is complaining about the wires are in factory location. PLug wires all routed away from other wires, but IDK if that would make a difference since I use racing wires with the best RFI shielding you can get that I know of. I havent replaced the IAC yet, just the TPS since it popped the code and the sensor didnt seem to work. Now the IAC is doing the same thing... Isnt working, but IDK if the sensor is truly bad or not. Im suspicous that the PCM needs to be re-flashed. Wut do u think?

 

Try this quick trick.....

Take off the intake box... so you can actually SEE the IAC pintle. Disconnect battery for five minutes.... Reconnect battery, have someone else turn the key to On, while you watch the pintle, it should run itself all the way closed, and then back off a bit. (do not try and start the engine while you are in there please...) If it doesn't do that, it's probably bad.

 

If I were a betting man....I would bet on grounds. Firewall to right head, battery to frame, batt to engine, batt to fender, etc. Check, clean, and tighten.

 

Hey man, I don't think reflashing it will cut it..sounds like you need to get another..I really hope that's not the case but it sound like it.. any other symptoms, smoke, stall, smell gas?

 

Yeah I will try that HeyYou. It is moving, cause I disconnected it and the idle stayed at 1200, then when I reconnected the IAC wire it brought the idle down to 550 or so. So I unplugged the IAC so it stays at that idle instead of going lower.

Gdstock, I am going to double check the grounds, but I am afraid u will lose your bet there. Thanks anyway!


Patt, My parts supplier told me of a NAPA store south of where I live by about 20 miles that can check the PCM. No gas smell except when the engine is cold. Prolly check the PCM, so I will post updates as it goes on.

As a final note, the engine runs really good even though the PCM keeps spitting codes like a llama. Strange... Runs good but PCM complains...

 

Ok, update today. Tried starting the truck, sputter cough spit codes again, misfire u name it, cant govern engine by itself, not regulating voltage, etc... What the world is going on here IDK. Prolly bad PCM Im thinking... Smells like gas too... Eeewww... PCM isnt controlling fuel/air or spark properly anymore.... Voltage goes up and down with engine speed now...

SO I am planning on new PCM.. SO wanted a few suggestions. Should I get a performance PCM or stock PCM? ANy brands recommended in particular? It's a 1996.

 

Some love the sct tuner, me I like my Mopar P pcm. As far as I know 96 is part obd1 and part obd2 or first year of obd2, sct did not support this year until about two years ago and I am still not convinced they have it all worked out. If I had any other year than a 96 I would indeed join the band wagon for the sct.

Mopar Performance pcm part #P5249935 Engine Controller (1996 5.9L ATX Ram) it is also one of the most expensive ones they offer.

 

What does the ATX stand for merc225hp? It is a 1996 and has OBD2, albeit only one upstream o2.