01 Trooper stalls

OK, car has been running great but last week it started to idle odd and then started dying. Hooked up a code reader and get the following codes: P1120, P1290, P1275, P1280, P1285. Usually in that order.

The APS was replaced this summer - dealer said it was shot, but I never saw the codes.

Now here's the trick - I replaced the part myself, but since I don't have a Tech2, I couldn't set it to 10-15% per directions. However, upon replacement the car worked fine with no codes.

The codes above are pointing more towards APS than TPS.

Anyone have any suggestions?

It could be the intake manifold gasket.

Could be, but I sprayed WD40 all around the gasket with no effect.

Should have changed idle somewhere.

Looks like I am going to turn over to the Dealer as you can only do so much without a Tech2 computer.

Thanks

Andrew

depending on where the break is on the gasket the carb cleaner spraying trick doesn't always work.

lay a new engine harness in it

Well, turned out to be rather difficult - even for isuzu.

It was the EGR - it had in internal short which was not passing the full 5v through to the TPS.

They'd never seen an EGR fail like this before. They had to call Isuzu.

So...if you ever see this again, now you know.

Andy

Can you describe how it would die? I have an odd cold weather dying problem that happens 1-2x/mo sometimes, so far this winter it's only happened once. Basically coming to a stop it just dies, no stuttering, I don't notice until I don't have power steering or until I hit the gas.

Upon decelleration, you could see the tach trying to drop to 0.

it would feel like a rough idle. you could try to rev it up and it would drop like a rock. When it didn't stall, it would run roughly, but barely.

during acceleration and cruising it was barely noticable.

cold weather SEEMED to make it worse, but I can't say for sure.

Andrew