Surging question from ported TB
Surging question from ported TB GUys,
Before I tore the car down to install teh F13, I have put on a Jantzer ported TB the previous week. After the install, the car started surging and idling very high.
I went back and checked for vacuume leaks and found none. I then took the TPS and IAT sensors off my stocker and swapped them thinking it may be the TPS. NO luck. still surged.
Im not sure what else can be wrong. I mean If i swapped the sensors It must be a vacuume leak that Im not picking up with the traditional gum-cuter test.
let me know what you may have seen in past experiances. Here is exactly what the car does.
start the car cold and it idles fine untill it goes into open loop. then it wants to idle at 1500.
driving along is fine then when I come to a light and depress the clutch the engine revs to 2k and hold for 4 sec, drops to 1500 and holds for 4 sec then dropps to 1k and stays.
THis sounds like a typical vacuume leak and the computer is trying to compensate but like I said, I cant find a leak.
The only code that auto tap pulled was idle higher than expected.
ANy help would be greatly apreciated. As I said the car is apart for the F13 install now so I wil probably have to deal with this again once its back together. I would hate to have to put the non ported one back on after the cam install. But the ideling issue is untolerable.
ANy thought appreciated.
Oh and yes I backed the set screw (throttle adj) all the way off and still idles high.
Thanks.
Before I tore the car down to install teh F13, I have put on a Jantzer ported TB the previous week. After the install, the car started surging and idling very high.
I went back and checked for vacuume leaks and found none. I then took the TPS and IAT sensors off my stocker and swapped them thinking it may be the TPS. NO luck. still surged.
Im not sure what else can be wrong. I mean If i swapped the sensors It must be a vacuume leak that Im not picking up with the traditional gum-cuter test.
let me know what you may have seen in past experiances. Here is exactly what the car does.
start the car cold and it idles fine untill it goes into open loop. then it wants to idle at 1500.
driving along is fine then when I come to a light and depress the clutch the engine revs to 2k and hold for 4 sec, drops to 1500 and holds for 4 sec then dropps to 1k and stays.
THis sounds like a typical vacuume leak and the computer is trying to compensate but like I said, I cant find a leak.
The only code that auto tap pulled was idle higher than expected.
ANy help would be greatly apreciated. As I said the car is apart for the F13 install now so I wil probably have to deal with this again once its back together. I would hate to have to put the non ported one back on after the cam install. But the ideling issue is untolerable.
ANy thought appreciated.
Oh and yes I backed the set screw (throttle adj) all the way off and still idles high.
Thanks.
ANyone. or am I being retarded and just need to get out there and look harder for a vacuum leak. I just wnat to make sure no one has run into this before and Im not overloking something.
Thanks again.
Thanks again.
I would inspect the IAC bore and plunger seat for residual
crud from the epoxy fill and powdercoating process. The
IAC that came with the TB may not be good either, can you
swap one from your stocker?
crud from the epoxy fill and powdercoating process. The
IAC that came with the TB may not be good either, can you
swap one from your stocker?
Also, make sure that the plate is sealing tightly against the bore. I had an issue with too much air causing surging. Try temporarily plugging the TB hole with a small screw and nut.
-T
-T
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Verdad Gallardo check check and check. forgeot to mention initally that I left the batery off over night, no custom tune yet, stock hole in throttle plate and I hope its not the MAP sensor as that wasnt changed. I havent however tried to plug the hole to check if the throttle plate may not be sealing enough when off throtle.
Ill try this friday, Thanks for the tips. Ill let you know what happenes after its back together. I cant wait
Ill try this friday, Thanks for the tips. Ill let you know what happenes after its back together. I cant wait