v85.0 engine randomly dies

[mtoliverjr]

the bleeding down was due to a hole in the FPR. that's been replaced. i found a nice tune-up walkthrough but it looks to involve some sensor cleanings that i'm not sure I'd pull off correctly the first time by myself. still hunting some related possibilities that'd be justified by those codes. not sure if any of them are really applicable besides the 85 and the 33

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[mtoliverjr]

just installed 2 new o2 sensors and reset the ecm with 30 minute disconnect/headlights on.

bout to drive and remap the ecm (hopefully).

both o2s look crappy to me, but the one on the right side is reddish in color (heavy oxidation?) while the driver side just looks worn. due to scatter shield and some bracket thing, i could only hand tighten the passenger side one and then just some vice pliers gently to turn it as much as i could without putting too much pressure on the sensor cylinder

i'll see how this works out. my friend has a vacuum pump that i'm going to borrow to test EGR valve and EVR, to see what the code 33 is all about.

i'm pretty set on the 85 being the adaptive lean limit reached. maybe the o2s will fix that. i'll trouble shoot the egr in a day or two, after i give the o2s a chance to make a difference.

the code 94 and 44 are still a mystery to me. common sense says it's pollutant control that was deleted long ago (cats, smog, something like that).

[mtoliverjr]

Finally got a check engine light to flash. Paper clip code pulling revealed a code 56, MAF circuit working above peak voltage. It was pretty beat up looking, and I'd cleaned it a couple times with Carb Cleaner instead of Electrical Component juice, so it's been replaced.

I reset the ECM with the unhook battery/turn on headlights method for 30 minutes. The car instantly ran better.

Day 2, after about 40 miles of ECM remapping, the sluggishness reared its head again.

My only code is a 33, but to my understanding the EGR only matters at highway speeds. Needless to say, i'll be vacuum testing it.

I plan to take off the t body and clean it thoroughly, the egr as well if possible (with a knowledge-able person watching on). Probably wind up replacing the EGR valve.

The small negative battery cable that grounds to fender apron is the oldest of my battery cables and probably should have been replaced since the 2 large cables have gone bad since I bought it 14 months ago. The small wire was carrying the entire load for the negative, so it got super hot and melted a couple of sheaths on nearby wires. It might be warming up and sending inconsistent signals.

But the overall problem remains sluggishness once warmed up. It wasn't present on a fresh ECM map, but once the 40-50 miles had been driven it returned.

I'm looking into the IAT(or ACT) as well as the ECT. I'm very car ignorant and am having a hard time locating them. I believe I see the ECT sticking straight upwards from the engine on the passenger side, above and behind thermostat housing. It has white threading visible.

The IAT originally ports into the air intake, to my understanding. The Trickflow intake that's on there has some port on the driver side as I look at it horizontally, but there's no sensor. It's just plugged up with a spacer of some kind it appears.

The IAT isn't located anywhere between the k/n filter and t body. Where are other popular relocation spots for this item?

It's a 302 bored over. The guy that sold it to me built it, but he hasn't replied to my question on the IAT location (Frankly I don't expect him to recall after all this time).

Otherwise I'm left with the ECM itself being garbage, but that seems like a last resort since IAT/ECT are < 30 bucks total.

The body ground wire will be switched, the egr evaluated/repaired, the tps adjusted along with timing.

Any other suggestions? Much appreciated, you guys have a good one!