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Nasty idle surge

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To me it sounds like you have a big vacuum leak after the throttle body. Either that or the throttle plate/cable is sticking open a tad. Run a boost leak test and pay close attention to the intake manifold and throttle body gaskets.
 
To me it sounds like you have a big vacuum leak after the throttle body. Either that or the throttle plate/cable is sticking open a tad. Run a boost leak test and pay close attention to the intake manifold and throttle body gaskets.

I did a boost leak test a month ago when thus started. I wasnt able to hear anything, I still need to spray soapy water around everywhere around my tb and intake. My bliss screw was leaking and I just filled it with gasket maker. Is there any other seals in the tb ? Ill loosen my tottle cable this weekend on saturday because I snug it up little a few months ago.

Just a question but does your surge go away after the car warms up? I have this issue and I have done everything except replace the entire TB because I'm thinking it's the FIAV now.

I used this thread to help:
http://www.dsmtuners.com/forums/articles-engine-fuel/191137-how-fix-your-idle-surge-problem.html

No, it does it after it warms up.
 
okay guys, here is an update. i found a vacuum leak coming from the fuel injectors, the vacuum caps on the throttle body, and the gasket from the elbow to tb. fixed all of them. Im still having the same problem. here is a updated video.


[ame]http://m.youtube.com/watch?v=gzQxmtbnGjs[/ame]
 
I will be doing a boost leak test tomarrow. But I have seen this guy on YouTube with the same issue as me. All he did was disconnect the tps sensor. I have a new tps sensor install, so now I'm thinking my idle switch came off adjustment while a was tightening it down. I'll have an update tomarrow. I'm hoping my tb shaft seals are not leaking as well. That's something that can wait until the summer.
 
Have you checked the ecu to make sure that it doesn't have any blown caps? I have a 94 Galant GS that does exactly the same thing and i'm pretty confident that the problem is the ecu because it have a few blown things in there :(
 
I believe I still has to be a vacuum leak. I keep finding all of these small leaks. The hoses are hard as well. I'm going to replace all vacuum lines this weekend. I'll keep you informed. It has gotten a lot better then what it was. It's now to the point where it just idels at 1500rpm.:thumb:

I believe I still has to be a vacuum leak. I keep finding all of these small leaks. The hoses are hard as well. I'm going to replace all vacuum lines this weekend. I'll keep you informed. It has gotten a lot better then what it was. It's now to the point where it just idels at 1500rpm.:thumb:

When I did the boost leak test. These leaks where very hard to hear. So if this is happing to you. Put your ear next to every vacuum line.
 
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