I have a -93mod FD. When engine get hot and radiator fan start, the engine begin to idle up and down, up and down, up and down betwen 1000-3000rpm!! have Someone any ideas what could be the problem??

 

underneath the intake tube is a screw,you need a long flat head screwdriver,adjust that,see what happens. youll see it if you look hard. but thatll usually fix it.

 

do you have a PowerFC? MIne is doing this also after I put in my PFC...This usually means it needs to be tuned...If you don't have a PFC then check for vac leaks...Also check to see if the TPS is within specs!

 

There's an SSP(Special Service Program, like a recall) on fluctuating idle on early 93's.

 

Did you do the idle learning feature? if you try to drive the car without doing it, the idle will hunt from 1-2k

 

yes i did the learning process...AC on idles fine--just everyother time it hunts...I'm going to try and tweek it tonight...

 

I can`t find it!! Is the adjust-screw on/under the Throttle body?

 

I don`t have a PFC! It`s a stock FD in original shape so far ... I have check for vac leaks but can`t find some. I will Try check the TPS

 

Have this to do with the ECU??

 

Well I just found my problem...One of the lines running to the solinoid(Double throttle control) had come off and the solinoid nipple was broken also!...Now it looks like it is time for silicone lines!

 

My 94 FD has done the same thing ever since i had the recall done for the fuel lines/fan modification. It will idle for 1 minute or so fine, then for a period of about 1-2 minutes, the rpm's go from 1-2.5k or so about 10 seperate times, each up and downswing lasting about 5 seconds. Not sure what to do really... car runs fine once it gets goin.

 

I blew out my lower intake manifold gasket and it hunted like that, do you smell gas when you give the car alotta throttle?

 

I don`t smell any gas, I have check for leaks, and used "starting gas" and I can`t find any leaks. But the problem only happens when the radiator fan start!

 

Now I have tried that!!! And it didn`t help!!

 

And Here is the answer: It was the ECU!!!!!!! Now the car works fine