# Rough Idle...Any help needed!



## royson345 (Jan 14, 2005)

My 89 max has a very rough Idle, but only when in drive. Sometimes it's so bad that when I'm sitting at stop lights I have to throw it into neutral just to keep my teeth from chattering. Any ideas?


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## Matt93SE (Sep 17, 2003)

it the RPM too low?

It should be 600-750 range.

How are your engine mounts?
all vacuum hoses connected and in good condition?
EGR valve stuck open?


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## royson345 (Jan 14, 2005)

It idles right around 700-800 rpm.

I'm not too sure about the hoses, but I'll check into it.

Is there any way I check to see if the EGR valve is sticking open?


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## royson345 (Jan 14, 2005)

ANybody have any ideas?


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## royson345 (Jan 14, 2005)

Don't mean to triple post but I also wanted to add a little more info. When the car is in park and I listen to the exhaust, I can hear it making a sputtering sound. It putts for a couple secs, stops, then starts again. maybe that will help diagnose the problem.


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## nismosleeper (Jan 16, 2005)

The 3rd gens are prone to exhaust leaks, so check for those, but ussually the idle is effected by the vacuum hoses. Also check your plugs and make sure they are working good.


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## royson345 (Jan 14, 2005)

By checking the vacuum hoses do you mean check them for holes or see if they're connected? I also heard something about squeezing them after the car has been running or something like that.

SO is the sputtering I'm hearing coming from the exhaust normal or is there something to it? It gets worse when it's in drive. When I switch from park to drive the RPM's drop dramatically then bump up to about 600 and that's when the idle gets rough.

Yeah I'm not that great with cars so you'll have to excuse my lack of knowledge.


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## nismosleeper (Jan 16, 2005)

Just make sure you don't hear any air leaks around the vacuum hoses. They should still be rubber-like (ie not stiff and scaly/cracked) Make sure they fit snuggly. The squeezing them bit will check to see if they are properly working, if so, the rpms will drop until you let go. (btw, When your brake is apllied, vacuum is involved.)


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## Evil_Twin (Dec 7, 2004)

Hey, I got a rough idle. Misfiring like crazy. I got Goodyear to diagnose the problem. They said my rear bank injectors all went out at the same time? Eh, I think I need to replace them cuz I don't know when they were replaced last. My hoses were starting to crack, so yeah.

Check your plugs, wires, distributor cap, and distributor rotor. Check for worn, oxidized or cracked anything when you look. If you run an ohm meter along each spark plug wire, you should get .5v at the most of resistance for a foot or something like that. There's a number, but I can't think of it off the top of my head right now.


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