88dth

I purchased an '88 Iroc back in September and it's in great shape after having a few major repairs done to it. The only thing left which I feel should be fixed is that it has a rough idle from time to time. I don't know much about cars unfortunately but I'm trying to teach myself as I go.

It starts up fine and runs great on the move, no loss of power whatsoever. But I notice it starts to sputter and has actually stalled on me a couples after coasting down my driveway in neutral. This has happened after driving it for a good 20 mins. It also happens at stop lights sometimes. This isn't a constant problem either, it only seems to happen once in a while.

I've been looking around this site and seen a few other people mention the same problem or slightly different. What I'm leaning towards it being is probably the IAC needs to be cleaned or replaced. Possibly the MAF as well but not too sure.

Any thoughts on this? Thanks.


edit-

Sorry forgot to mention it's a 305 TPI 5 speed if it matters.

five7kid

iTrader: (14)

Welcome aboard thirdgen.org.

Yes, that matters a lot.

The IAC is a good place to start. After you know your ignition is up to snuff (spark plugs, spark plug wires, distributor cap rotor, etc.).

88dth

Thanks for the welcome.

I'm pretty sure the ignition is good since it has new wires and plugs as well as a few other things. I'll check the cap though.

I took it for a run yesterday and it was having more of the same troubles. Another thing I noticed (that could just be a coincidence) but after it's been parked on an incline seems to effect it as well. Don't really see how that would make a difference, but like I said it could just be a coincidence. Always seems fine when I start it up in the garage (since it's flat). It idles smooth.

89Camaro89MI

iTrader: (2)

Yeah, Welcome.

I've read a lot of rough/stalling posts - it's pretty common. When I had trouble with mine at stop lights, deleting the EGR system did the trick. You might also look into replacing/deleting the catalytic converter - if it gets excessively hot after a short time, it could be collapsed - or other exhaust bits that could impede airflow.

The first thing I would do is get new spark plugs. Maybe air filter. If that doesn't do the trick, work your way up into fixing more expensive problems like sensors that affect the air/fuel delivery. MAF is probably the most expensive sensor - my philosophy has always been rule the cheap stuff out first.

Good luck. Let us know how it goes.

88dth

One of the major things I had replaced was the cat converter. So it can't be that. I can't delete it since I wouldn't pass Air Care (dunno if the Air Care program is required in the US, but it is in Canada).

I have a Haynes manual and have been poking around in it. I've bookmarked a few possibilities so I'll have a look next chance I get this week. I'll check the air systems, plugs, wires, and distributor first, then if I can't get it solved then start opening up the throttle body and have a look inside. All I'd do is be cleaning inside it, doubt I'd have to replace anything since it's fairly new also. The previous owner kept the car in pristine condition and cleanliness, inside, outside and under the hood.

89Camaro89MI

iTrader: (2)

It differs state by state down here. Here in Michigan, there's none (so I always delete them).

The Haynes Manuals are pretty good but some of the more in-depth stuff you'll need to come here for.