rough idle when engine is in gear - Toyota Nation Forum : Toyota Car and Truck Forums

joker111481 · 01-30-2007, 09:54 AM

I have a '90 Corolla DX (4A-FE) and recently it started idling very rough, almost jumpy when it is in gear. When I put it in Neutral or Park, it doesn't idle rough, but in Drive, 2nd, and Reverse it is extremely rough, it shakes a lot harder than the car should. As soon as I accelerate and drive off, it's not rough anymore, so the problem is only happening when at a complete stop. Anyone had this problem before and have any ideas as to what the cause could be?

It is not due for an oil change for quite some time and I recently had the transmisson pan gasket replaced because the old one was shot. Also I recently I had a short in the electrical system that caused the brakes to control the headlights and the headlights to control the brake lights, but this has since been fixed and works correctly now. Those are the only two things that I have repaired recently.

Thanks everyone.

ghost_ryder35 · 01-30-2007, 12:16 PM

dirty air filter, fuel filter, fouled out spark plugs, dizzy cap and rotor could need replacing. run a bottle of fuel injector cleaner through it and see if that helps.

tashirosgt · 01-30-2007, 01:22 PM

When did you last set the timing and check the idle speed setting?

joker111481 · 01-30-2007, 03:29 PM

Thanks guys, I'll check all those things and see if it makes an improvement.

punter · 01-30-2007, 05:06 PM

I'd say you've got alot of miles on your car?

Sounds like worn engine mounts to me.

darcsyde · 01-30-2007, 05:32 PM

yeah was going to say that too, maybe the mounts are going

joker111481 · 01-30-2007, 07:34 PM

Quote:

Originally Posted by punter

I'd say you've got alot of miles on your car?

Sounds like worn engine mounts to me.

A little over 144K on the original engine and tranny, so it's possible the mounts are going, makes sense to me. Lately a lot of things have started to need replacing, which I expect on a 17 year old car. I checked the air filter today and it does not need replacing yet, and I'm going to check some more things and now that you suggested it I'll check the mounts too, thanks!

90 GP · 01-31-2007, 03:57 PM

Check to see if you have vaccuum leaks which could make it run rough too.

fistofmeat · 02-01-2007, 02:09 AM

144k isn't really too much, especially on these engines... i an mine to nearly 180k before the engine blew. my dad never mentioned to tell me that the oil pressure light didn't work, and this was before i was car saavy (was lazier then too), but it killed itself after not having any oil maintainence in a couple of years (mechanic tore it apart only to find that it was bone dry), so it was entirely the drivers fault, and the clutch didn't wear out until past the 200k mark... i'm just gonna throw this out there, could it be that the idle is set too low?

joker111481 · 02-01-2007, 09:59 AM

Quote:

Originally Posted by 90 GP

Check to see if you have vaccuum leaks which could make it run rough too.

Definately, that is another idea that crossed my mind. Thanks for reminding me.

joker111481 · 02-01-2007, 10:02 AM

Quote:

Originally Posted by fistofmeat

144k isn't really too much, especially on these engines... i an mine to nearly 180k before the engine blew. my dad never mentioned to tell me that the oil pressure light didn't work, and this was before i was car saavy (was lazier then too), but it killed itself after not having any oil maintainence in a couple of years (mechanic tore it apart only to find that it was bone dry), so it was entirely the drivers fault, and the clutch didn't wear out until past the 200k mark... i'm just gonna throw this out there, could it be that the idle is set too low?

Yeah, that is a distinct possibility. I haven't checked the idle yet, but it's on my list of things to check. I have some time this weekend, I'm going to check over everything.

Thanks guys, you all thought of a lot of things that I didn't.

ghost_ryder35 · 02-01-2007, 10:07 AM

if it turns out you have a torn motor mount, fill them with silicone

cheap $5 dollar fix

joker111481 · 02-01-2007, 10:14 AM

Quote:

Originally Posted by ghost_ryder35

if it turns out you have a torn motor mount, fill them with silicone

cheap $5 dollar fix

Awesome, thanks.

fistofmeat · 02-02-2007, 02:47 AM

Quote:

Originally Posted by ghost_ryder35

if it turns out you have a torn motor mount, fill them with silicone

cheap $5 dollar fix

so getto it's not even funny... but then again, i'd probably do it too lol, whatever works

joker111481 · 02-12-2007, 10:33 AM

Thanks for all the suggestions everyone, they helped me a lot in diagnosing the problem. I now have a new PCV valve, new fuel filter, new plugs, new distributor rotor and cap assembly and ignition cables. She's purring like a kitten once again, thanks all!