i've been searching the forum about this idle problem i've been having, idle bounces up and down from 9k to 13k and back down to 9k, and i was wondering how hard is it to replace the lim gasket for someone who hasn't had much experience workin on an fd?

 

I hope its not from 9k(9000 rpm) to 13k(13000 rpm) because then you will have a different problen on your hands. What is your vacuum like? Check to make sure the vacuum line on the map sensor didn't come off? Is the car vibrating? Were you driving it hard before this started to happen? What kind of mods do you have? Is there a lot of smoke coming out of the exhaust? These are just some of the questions I have for you.

R.K.

 

Spray some parts cleaner or equivelent around the gasket area. Rpm's should make a noticeable difference up or down( depends on if you use something that is combustable or not to spraY) Also one of the ones I replaced sounded like chitty chitty bang bang when it idled.( for those too young for chitty, it sounded like a bubble maker). The job itself is pretty involved. You could do it with the right amount of time and patience.( If you are mechanically inclined, if not search for someone in the area that is and will help)

 

i have 20in of vacume. it starts most of the time when i start the car from cold, the car does vibrate, and your right its not 9k-13k its 900-1300 my mods are apexi intake, and the trust pe2 catback, and where is the map sensor located?

 

Firewall, just to the right of the UIM, but to the left of teh master cylinder... Should say Denso Map or something, has a vaccum line running to it....

 

just check the map sensor and yes it is connected and DC thanks for the locationo

 

It's not technically hard, but it's enough work that you want to be pretty sure that's the problem before you tackle it. How much experience do you have? Have you ever taken off your UIM? That's just the beginning. You need to take the upper intake, airpump, y-pipe, downpipe, turbos, and lower intake off.

I attached a long, small hose from an injector cleaner can to a coathanger wire so that I could direct it to the hard to reach LIM gasket area to test for leaks. Work bottom up. Don't test around the upper gasket first because the cleaner can flow down and mislead you into thinking it's the upper gasket. When the cleaner fills the leak, the idle surging will tend to smooth out for a bit.

Pull the electrical connection on the airpump (if you have one). If that affects the idle surging it's another sign that you have a leak.

Replacing the LIM gasket will take a lot of time if you've never done it before. On the plus side, afterwards you'll feel you know a lot more about your car and you'll be less dependent on dealer mechanics in the future.

Good luck!