Does anyone know how to adjust the IAC valve???

Krimzen · 03-27-2007, 09:30 PM

I got an 88 Mr2 with a swapped GZE engine. I have put on some upgrades like cams and pulleys, FPR (35 PSI), high flow fuel pump and injectors (10% higher than stock). The car is idling way to high at 3000 RPM and increased to 3500 RPMS. I also have the AFM from a Mazda RX7 installed to increase the size of the throat.

I tried putting the original GZE AFM back on and it stilled idled and ran the same way. (No Engine light)

It is when I tried the N/A AFM that the car started idling at a wobbly 800 RPM, however, the exhaust was smoking a clear whitish color and smelling alot like gasoline. Also, it finally tripped the engine light which coded out to a bad AFM.

It ran at the correct ilde with the NA AFM installed, but it ran rich and idled rough. Both AFM's From the GZE and the RX7 did not make the engine light go on.

I think I have something else besides the RX7 AFM that is messing up the idle.

Does anyone know a way to adust the Idle conrol valve on the GZE? Maybe I just need to turn it down somehow.

Is 35 PSI for fuel pressure a little to high? Could the PSI be affecting my idle.

toyotaspeed90 · 04-04-2007, 08:49 PM

35psi is too low...... i doubt that's causing a bad idle..... however, if not, you should be running a rising rate adjustable fpr.... not a static one

you should probably give more info..... what electronics is it on? what engine is it? (ie, is it a stock 88/89 s/c engine and electronics.... or is it a JDM motor with some aftermarket system....)... i would assume it's stock since it still utilizes an afm....

3,000 is high.... just about too high for the idle air control valve to hold it that high.... check the idle screw to make sure it isn't fully open (which is on the TB). The control valve itself is not adjustable.

Krimzen · 04-09-2007, 11:05 PM

I can adjust it a little higher but I am interested in the rising rate. What brand would you recommend? The motor is a JDM 4agze (no egr), I am running the stock ECU. The only thing diff. is the AFM from the RX7, which does not trip the engine light. It sounds like its ready to run good so long as I get the idle correct. I was reading a code before for a bad A/C circuit. What do you think that could mean? I removed the A/C altogether.

I appreciate the help.

Jerry.

03-27-2007, 09:30 PM	#1 (permalink)
Krimzen No Skills Join Date: May 2005 Location: Marietta, GA Posts: 62 Thanks: 8 Thanked 3 Times in 3 Posts iTrader Rating: (0/0% )	Does anyone know how to adjust the IAC valve??? I got an 88 Mr2 with a swapped GZE engine. I have put on some upgrades like cams and pulleys, FPR (35 PSI), high flow fuel pump and injectors (10% higher than stock). The car is idling way to high at 3000 RPM and increased to 3500 RPMS. I also have the AFM from a Mazda RX7 installed to increase the size of the throat. I tried putting the original GZE AFM back on and it stilled idled and ran the same way. (No Engine light) It is when I tried the N/A AFM that the car started idling at a wobbly 800 RPM, however, the exhaust was smoking a clear whitish color and smelling alot like gasoline. Also, it finally tripped the engine light which coded out to a bad AFM. It ran at the correct ilde with the NA AFM installed, but it ran rich and idled rough. Both AFM's From the GZE and the RX7 did not make the engine light go on. I think I have something else besides the RX7 AFM that is messing up the idle. Does anyone know a way to adust the Idle conrol valve on the GZE? Maybe I just need to turn it down somehow. Is 35 PSI for fuel pressure a little to high? Could the PSI be affecting my idle.

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04-04-2007, 08:49 PM	#2 (permalink)
toyotaspeed90 No Skills Join Date: Jun 2006 Location: Bellingham, WA Posts: 646 Thanks: 0 Thanked 46 Times in 46 Posts My Google Map iTrader Rating: (0/0% )	35psi is too low...... i doubt that's causing a bad idle..... however, if not, you should be running a rising rate adjustable fpr.... not a static one you should probably give more info..... what electronics is it on? what engine is it? (ie, is it a stock 88/89 s/c engine and electronics.... or is it a JDM motor with some aftermarket system....)... i would assume it's stock since it still utilizes an afm.... 3,000 is high.... just about too high for the idle air control valve to hold it that high.... check the idle screw to make sure it isn't fully open (which is on the TB). The control valve itself is not adjustable.

04-09-2007, 11:05 PM	#3 (permalink)
Krimzen No Skills Join Date: May 2005 Location: Marietta, GA Posts: 62 Thanks: 8 Thanked 3 Times in 3 Posts iTrader Rating: (0/0% )	I can adjust it a little higher but I am interested in the rising rate. What brand would you recommend? The motor is a JDM 4agze (no egr), I am running the stock ECU. The only thing diff. is the AFM from the RX7, which does not trip the engine light. It sounds like its ready to run good so long as I get the idle correct. I was reading a code before for a bad A/C circuit. What do you think that could mean? I removed the A/C altogether. I appreciate the help. Jerry.