high idle and surging at low rpm need help
#1
high idle and surging at low rpm need help
ok so i was having my car tuned, and the tuner call me and told me i have a vaccum leak or something, and he couldnt get it to idle right. so rather than have him fix it i decided to try and to it myself, so i have replaced the intake gaskets, tps, and iac, its a fast 90/90 so i took it apart and checked for cracks and could not see any cracks. (and yes i have the button head bolts on the valley cover). but anyway i could no see any cracks what so ever. i looked at my brake booster hose and didnt see any problems there. i dont have a pvc system so im good there. no air or egr so im good there. checked the vaccum line at the rear passenger side of the intake. couldnt find any problems there. anyone got any idea what to check next!! i dont think its the tune, the tuner i took it to has a very good rep! but i gotta fix this issue so i can finish having him tune it. im puzzled. any help would be awsome
#2
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get it all back together, let it idle and spray some carb cleaner or brake clean around the base of the intake and all the lines. also check to make sure the lines are connected in the right spot. you never know, an evap line to the fuel tank maybe off. at least this might help you get closer to your problem
#3
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Has the car been tuned before; or was this the initial tune? Before throwing more parts at it you need to datalog the car to see what's actually going on. Is it throwing any codes?
#4
sorry the high idle is when the car is in nuetral and rolling and it hangs at 2k while the car is rolling to a stop once the car comes to a stop the idle slowly goes down. and yeah i tuned it with hp tuners a year and a half ago or so. just to kinda get it close. and no codes
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sorry the high idle is when the car is in nuetral and rolling and it hangs at 2k while the car is rolling to a stop once the car comes to a stop the idle slowly goes down. and yeah i tuned it with hp tuners a year and a half ago or so. just to kinda get it close. and no codes
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#12
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Look at the picture above I posted. This will keep constant pressure on the MAP sensor so there is always a positive seal between the sensor and intake. Even though the MAP sensor has a small orange ribbed gasket that goes over the orifice for a good seal, you still need some pressure to hold it into place. The stock GM manifolds do a great job, unlike the FAST (at least the 90mm) which has no clip to hold it into place. Fix that before continuing the tune.
#13
Look at the picture above I posted. This will keep constant pressure on the MAP sensor so there is always a positive seal between the sensor and intake. Even though the MAP sensor has a small orange ribbed gasket that goes over the orifice for a good seal, you still need some pressure to hold it into place. The stock GM manifolds do a great job, unlike the FAST (at least the 90mm) which has no clip to hold it into place. Fix that before continuing the tune.
#15
I did kinda lean toward that, i just think the guy is a real respectable tuner, im not gonna say who it is, but i have never heard one thing bad about him, the shop only deals with mostly lsx's so i figured they knew what they where talking about. i just dont know another tuner in my area honestly