idle not increasing when a/c is turned on.. new iac and nothing

[cubanfisher]

idle not increasing when a/c is turned on.. new iac and nothing. i've thought of everything.

can the intake manifold be carboned up? please someone help. ive been dealing with this forever!

94 ranger 2.3l auto

 

[cubanfisher]

anyone?

 

[cubanfisher]

bump... please anyone....

 

[Hardwareman]

Sorry I can't help you out with this problem. I'm having the same problem and also swapped out the IAC. I'll let you know what mine is if/when I figure it out.

Let me know what it is if you figure it out first buddy! Later.




Allen

 

[cubanfisher]

bump... please anyone have any ideas?

 

[Hardwareman]

At least you're not giving up. Still having the same issue as well. Have you checked voltage coming from the PCM?




Allen

 

[fireguy12117]

sorry i cannot pinpoint this one either, but is the clutch cycling like normal? your AC does work? to my knowledge, there is only the AC clutch relay and the IAC coming from the PCM to regulate the action of the idle in this case. the PCM is going to decide (however it does...) when to kick up the idle and turn the clutch on. id check the ports of the intake where the ICA bypasses the throttle plate, and check all your wiring, make sure everythings plugged in tight, and wiring itself is intact with a simple continuity test between the PCM and each device. i had a broken wire inside of the harness for my 4.0 IAC that no one at a shop could figure out, it was a simple continuity test in an apartment complex parking lot with a $5 meter.

 

[cubanfisher]

ill try to check the wiring but about the cleaning, how welll should i clean it? like remove the intake, and behind the butterfly with a wire brush? can i use a decarbonizer?

anyone know wat my voltage reading should be at the iac?

 

[shadetree]

When your a/c turns on, does it kill the engine, cause a drop in rpm that doesn't recover, or is it slow to recover????shady

 

[Bob Ayers]

Could be a wiring problem to the IAC. With the AC off, and engine idling, unplug the IAC and see if your idle drops. If it doesn't, then you possibly
have a wiring problem between the PCM and IAC valve.

 

[Hardwareman]

When your a/c turns on, does it kill the engine, cause a drop in rpm that doesn't recover, or is it slow to recover????shady

That's exactly what mine's doing Shady!

If I turn on my A/C, the engine rpm's drop sooooo bad it causes my throwout bearing to rattle. I just replaced my throwout and pilot bearings about 3 days ago too but that does'nt help. The motor just bogs down too much you know?

It does'nt recover at all. I've both cleaned and replaced the IAC but it's still doing it. I'm starting to consider a wiring problem between the PCM and IAC like Bob said.



Allen

 

[cubanfisher]

well mine idles great when a/c is off and then when turned on rpms drop and everything shakes. does not pick up at all. im assuming that it should increase with the power steering switch aswell and it does not

according the this vaccuum diagram theres a vacuum valve that says activated by max air. any chance this could do anything with our problem if so where is it

 

[cubanfisher]

according to the manual the iac's ohm reading should be between 7 and 13 ohms. but im just wondering whats the voltage from the pcm supposed to be

 

[Hardwareman]

according to the manual the iac's ohm reading should be between 7 and 13 ohms. but im just wondering whats the voltage from the pcm supposed to be

At least 10.5 volts according to my manual.




Allen

 

[cubanfisher]

hey btw on ur ranger, are you getting that voltage to your iac? im just trying to compare our similar problems, any chance you have a problem with shifting on ur truck. i kinda hope you hope and kinda don't lol, if you do im wondering if theres a vacuum leak some where.