993 won't idle
I have a 1995 993, so no SAI. I was trying to go through and get this to pass CA smog. The low speed HC were a little high. So, I took off and cleaned the Idle control valve with carb and choke cleaner inside of it and electric contact spray on the contacts on both it and the plug where it connects to. Checked the ISV electronically off and on the car and it seemed to work fine. Next, I removed and cleaned the air sensor in the intake with sensor cleaner and the contacts with contact cleaner. Next I removed the MAF and cleaned it with MAF cleaner and cleaned the contacts with electric contact cleaner. Put it all together so I could raise the car to change out the Oxygen sensor. Low and behold, it wouldn't start. Finally I gave it a little extra gas and it started. It will idle down to about 1000 rpm but as soon as I let my foot off the gas, it dies. Any ideas?
Also, prior to all this work, I changed out the plugs, rotors and caps, spark plug wires, air and fuel filters, etc and I was driving it around fine. Just couldn't pass CA smog so I did the previously mentioned work. Thanks in advance |
ISV? You mean ICV or? If indeed we’re talking idle control valve, and you cleaned it, I’d double check everything to do with it as they’re a bit of a ***** to get reinstalled correctly. If you have access to a known good one, try it, or replace the one you have. I’m not on this or any 993 forum much anymore but rennlist is by far the best attended forum for the 993.
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Originally Posted by Beta Steve
(Post 4949606)
ISV? You mean ICV or? If indeed we’re talking idle control valve, and you cleaned it, I’d double check everything to do with it as they’re a bit of a ***** to get reinstalled correctly. If you have access to a known good one, try it, or replace the one you have. I’m not on this or any 993 forum much anymore but rennlist is by far the best attended forum for the 993.
Thanks for the advice to check out rennlist. I had been on it for BMW stuff but I may have to mosey on over to the Porsche side of things. Thanks for everything Beta Steve! |
Originally Posted by speedheur
(Post 4950653)
A faulty temperature sensor can cause starting and rough idling problems. If this sensor gives a bad reading, the ECU can send an incorrect signal to the fuel injection and ignition.
Thanks in advance speedheur |
Since it started right after you cleaned those sensors, I'd double-check all the connections to the MAF and air sensor. Make sure they're snug and clean.
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