12v idle problem. IAC?
02-17-2008, 09:57 PM
#1
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12v idle problem. IAC?
once it warms up and goes into closed loop it will idle steady at 500-800 rpms for 15-20 seconds then it will drop down and almost stall out. its worse if i rev it up. as it drops back down it will almost stall then catch its self rev up to 1200 or so then fall again and stall out. I thought it might be the idle air control. but im not sure. any ideas?
02-18-2008, 01:01 AM
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I just used carb cleaner.
It made it a bit better, but ended up being a vacuum leak on mine (1992 2.8 12v). The line from the brake booster goes thru some check valves? and has a few connections between the driver's side valve cover and the intake manifold.
Once I fixed the leaks, it idles great!
Once I fixed the leaks, it idles great!
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02-18-2008, 08:21 AM
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as suggested...
... my two guesses would be ICV or vacuum hoses. Vac hoses are a simple fix on the 12v - couldn't hurt to do them anyway. As far as the ICV, Kris Hansen has a walkthrough for removing the ICV. I pulled mine out and cleaned it with carb cleaner. And FYI, as I recall it seemed to measure within the electrical specs Kris mentions - this does not mean the ICV is ok.
Anyway, pulling it the first time will require a lot of finagling. After cleaning, the problem improved, but returned a few months later. At that point I bought a replacement all-metal ICV from ECS and it went in quickly and solved the problem.
Anyway, pulling it the first time will require a lot of finagling. After cleaning, the problem improved, but returned a few months later. At that point I bought a replacement all-metal ICV from ECS and it went in quickly and solved the problem.
02-18-2008, 08:39 AM
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how much did the ICV run you?
i guess ill try replacing vacuum lines first. theyre cheaper. and if cleaning it doesnt work then ill probably have to buy a new one. thanks for the help.
02-18-2008, 10:48 AM
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it's been at least a couple years...
... I want to say maybe $200 or so like Mr Paul mentioned. I'd definitely do the vac lines either way - should only cost you a few bucks for a few feet of rubber hose. Cleaning the ICV won't cost you anything either, and at least that way you can get a good idea whether it's causing your problem in the process. If cleaning it improves the situation and then it gets worse again, I replaced the ICV - I guess if you really wanted to be cheap you could just keep cleaning it.