You're having a nice run...wish I could answer your questions. Hang in there.

Glad to hear that you making progress, but I hate to hear about AC. ON the oil pressure guage, you might want to cleanup blown oil that seeped from the leaking valve covers. If yours is like the the 95s that I've owned, you will find major seepage on the oil pressure sensor and leads to the starter. The tranny leads will have similar buildups.

Your idle sounds a bit low. I'd think you'd run750 or better. Also, did you replace plug wires? I've forgotten.

ON the bucking at 90MPH!!!! I cannot imagine...my 95s have been 5spd <img src="/forums/images/graemlins/scared.gif" alt="" />.

Im kind of guessing at idle from the tach on dash, its not too accurate. I could put a real tach on it, but it is what it is anyway, the ECU controls it.

No, I havent replaced plug wires...yet. That wouldnt make the idiot lights come on, so there is still something else going on, even if its not responsible for the rpm fluctuations under acceleration. I did regap the plugs when this started at the same time I changed the fuel filter.


Might be a good time to bring this up. Spark has seemed weak for a long time. Occasionally over the last few yrs (once a yr or so) it would develop a rough idle and rough running under acceleration. In those cases there was usually a cylinder that noticeably wasnt contributing its fair share. Simply returning plug gaps to spec would clear it up. I know when it was much newer that didnt happen. But it never dropped rpms and then picked them back up the way it does now.

Once, I even developed a bad spark plug. I could swap it between cylinders and the miss would move with it. Never had that before in my life, but it happened. Changed out one plug and it ran great again.

Maybe the oil in the plug tubes had something to do with that stuff.

Have you tried running it at night (in the dark), looking for arcing in the ignition system?

Yes, no sign of any arcs. I drove it tonight just a few miles to the store. No problems. Oil gauge stays in normal zone at idle UNTIL the engine warms up, then its starts dropping out below 1000 rpm.

At least the oil guage is losing voltage or ground or something when it warms up. Is it related? or just another dang problem? <img src="/forums/images/graemlins/confused.gif" alt="" /> I suppose Ill get to the bottom eventually. Probably after I replace alternator, ignition module, ecm, tcm, etc.


Id probably take it to a dealer and let them solve it, but the nearest Isuzu dealer is now about 80 miles from me. Three dealerships within 10 miles here when I bought it all quit selling Isuzu, I think GM ruined them when they started rebadging GM vehicles as isuzus.

I dont think Honda sold the trooper, only the passport. I think Acura sold it some years, but not very many and not many vehicles. Theyd probably not be much help.

Yeah the Acura SLX was a rebadged Trooper...and of course Acura is a Honda brand. I wouldn't expect a Honda dealer to know much about them though.

drove it some more tonight, disconnect vsv's for the cannister purge and egr to see if somehow those things might be causing trouble. It took `20 min of driving, but eventually it would start to act up under hard acceleration even with those disconnected. Surprising that I dont get an EGR code with the EGR vsv unplugged.

After 3o min of driving the airbag light came on under heavy acceleration for a couple seconds, then went out.

I am still thinking it is an electrical issue. The battery problem could be incidental or it may have been contributing to the problem. I just am leaning towards a flakey alternator with poor wiring (somewhere) a close second possibility.

I know this this is frustrating, but don't go throwing parts at it. Clear the codes (disconnect the battery for 30mins?) and then drive it until it gets flakey again. Get it scanned. Start there. Also, get the alternator tested. While bench testing it may be "better", I would have them do it on the vehicle for starters because they are a PITA to get off of these vehicles, IIRC.

Worst case, pull it and find an auto electrical shop to have them look at it. I would trust them a bit better than the monkeys at your local part store/mini-motorcycle showroom.

Go from there. Unless you are getting codes for bad parts (ECU, TCU ect) don't just throw parts at it. You've determined it is still acting up, so move on to the next diagnostic step (test the alt).

I don't remember clearly enough, but is your's one of the 3.2s who like clog up EGR valves? If so, it might be something worth looking at. A sticky valve could explain the running issues.

Good Luck,
Michael

It has no codes, nothing.

The fluctuation is so rhythmic, Its like when the tcm tells the ecm to drop rpms for a shift, but no shift happens. Up down up down up down up down by several hundred rpm about once per second. But I already ran it in manual with tcm disconnected and it still happened. It happens with everything disconneted, except the coolant temp sensor, thats the only one I havent tried unplugging yet.

My egr wasnt dirty, but the port in the common chamber was totally crudded over, so I cleaned all that up. I think that gave me an egr and lean O2 code before all this started, but its fixed now.

The intermittent airbag light is about the only clue now that something unusual electrical is going on.

Can they test an alt on a vehicle? That beats pulling it.

Well, tonight went to drive it somewhere. Ive driven it >100 miles since changing the battery and clamps,and it never died or tried to, but MOST of that was high speed driving evaluating if the acceleration problem was there.

Sitting at a stoplights for a while, after it had been operating for ~20 min, the check transmission and airbag lights came on, battery voltage pegged out >16, and light squeal sound started. I shifted to Neutral and revved the accel, the squeal gets louder, When I tried to drive forward in Drive, the vehicle didnt move very fast,like it was in wrong gear, So I manually shift to 2 to start off, and start to drive, and it starts dieing. It dies. I shift to P and restart, and it dies again. I start it again, and everything is fine, works normally, squeal is gone, and we drive away. Later when I push accel hard, it starts the problem there again.

Seems like maybe the alternator almost seizes sometimes or something? Since the AC seized up, I took the belt off there and the only things left to squeal are the alt and ps.