Hi Everyone,

I just bought a 94 3rd gen with 64000miles on it, the car never been modify but the idle is at 1500rpm after warm up. When I start the engine, its around 2000rpm. Does anyone know what is the problem and how can I fix it. Also, the engine base is very hot. THANK. PLEASE HELP

 

Well, the FD has an automatic warm-up thingy (notice my technical skills) where it will jump in RPMs after a cold start to help the engine warm up a bit. After a few seconds, it should drop down. The idle can be adjusted via a bolt and nut by the throttle body. If you pop the hood, you should see where the throttle cable connects to the throttle. there is a bolt nearby that adjusts the sitting position (idle position) of this throttle arm. Just advust the nut, and it should be fine. Hope that helped

 

I think my FD should have some problem coz the idle should be auto adjust. I think not only adjust the idle from that throttle body. It should have other problems affect the idle keep in 1500rpm and the engine base is very hot. Does all the 7's expert have any comment and advise. THANKS !!

 

Couldn't follow that paragraph for a lick

but, I have a 94 with 63,400 miles and have the same idle problem. The nut on the throttle cable doesn't do anything, I'm in the process of moving on to the dapshot. I noticed if I push against the throttle lever that rests against it, the idle drops a bit.

A lot of people seem to have this issue and some leave it, some don't. Might want to check your cruise control cable as well. Had to disconnect mine because it was too short, or something, and was causing the TB to stay open a tad making it idle at about 3K. Thinking of just removing my cruise altogether

 

Start the car in 1st and see what happens. Thats what I was told to do when I bought my car and it keeps the RPMS low.

 

I moved 2 bolts on my TB when I polished it and they both affect the idle. The second adjuster is actually an allen head stud with a jamb nut. It hold the primary butterflies open in the TB. Half a turn is all it took to make my car run fine again..... hope this helps you...

I think they all run hot there guy.......

 

you may do a search for TPS or Throttle Position Sensor. It can cause some funky idling, too.

 

Loosen the throttle cable.

 

Get a shop manual if you don't have one already. There are dozens of things that can cause this. I have a related problem as well. It's takes most people several months to narrow down the cause. Good luck!

 

adjust your tps sensor out of range

 

No No, dont touch your TPS.
The car reving up to 3k at start up is the AWS system (accelerated warm up start), You can actually eleminate it if you really want to. The easy way to avoid it is to start the car in 1st gear, or just blip the throttle and it will fall back down.
Ok now there are two idle adjustment screws, One on the front ate the top of the throttle body and one underneath the intake elbow. You should be able to drop your idle from there. Other than that you need an ECU to make any other adjustmenst to idle/fuel controll.

downlaod a workshop manual from www.iluvmyrx7.com if you dont already have one.

But trust me that you would rather not play with your TPS.

 

Let me get this right, Is your car on 1500 rpm on idle or only after you start the car? If it stays at 1500 rpm on idle that means your lower manifold gasket is blown!!! That is normal for cars that are from 92 to 94 since they used paper gasket instead of metal. Gasket is cheap $10 or so but the labor is the expensive part. About $500 to $800 in labor. Hope this helps ....

 

Dave is right... The 2000+ RPM is the Accelerated warmup. Start the car in gear.

If it stays high... 1500 as you say AFTER WARM UP... Check the idle screws and your throttle cable.

I fixed 3 FD idle problems and stalling by checking and adjusting the throttle cable.


Oh, and YES it could be the Manifold gaskets!

 

yes, the idle keeps on 1500rpm all the time until I shut down the engine. (when I start to warm up the car is around 2000rpm). So, you think I need to check the lower intake manifold gasket first? hope it can help. Thanks

 

I don't agree! Yes, that could be on cause...but there are many more possible causes. That is the fun of FD idle problems.

Does the idle respond to electrical load? Does it settle to 1500 rpm quickly when coming to a stop or does it float for awhile. My best advice is start with a boost gauge. See what vaccum you are at at idle. If it is within specs, I'd look at the solenoids. If it is off I'd look for leaks. Doesn't have to be something expensive, could be something as simple a loose hose.