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Continuing along my path of troubleshooting....working on a funky idle.
JRSC BBK - Car idles with an odd miss. Got it on a dyno and it idles at 19 AFR. Looking at the vac readings - wobbles between 12-14 with idle miss (up this high 15 is the norm)....holds boost just fine. Gearing down a hill, it will hit 17/18 whereas 20 in norm.
So the guess is a vacuum leak. Went around the car hosing it down with spray listening for a change in idle...nada. All connections are über tight too boot. Final test was done on the by-pass actuator....
First test - disconnect vac hose, pull open by-pass, place finger over nipple on actuator and let go. By-pass closed with no problems :/ So, I then hooked up the MightyVac to the actuator and tried to vacuum the by-pass open. No dice....so it must be leaking, but I hook it up and it's working ok. SO....
Final test - Disconnect actuator, zip tie the by-pass open and plug the vac line (thereby eliminating the leaky part). Car still idles like poop and I get the same vac readings. Same odd miss. So I found a leaky part, but not my problem part.
Could the IAC be the culprit? Would it leak vacuum? Obviously it could cause an odd idle, but could it cause the car to go lean like that?
I plan on disconnecting the IAC and seeing the result. Also thinking about maybe disconnecting the TPS after that and seeing how it idles.
Any other ideas are welcome. Thanks
JRSC BBK - Car idles with an odd miss. Got it on a dyno and it idles at 19 AFR. Looking at the vac readings - wobbles between 12-14 with idle miss (up this high 15 is the norm)....holds boost just fine. Gearing down a hill, it will hit 17/18 whereas 20 in norm.
So the guess is a vacuum leak. Went around the car hosing it down with spray listening for a change in idle...nada. All connections are über tight too boot. Final test was done on the by-pass actuator....
First test - disconnect vac hose, pull open by-pass, place finger over nipple on actuator and let go. By-pass closed with no problems :/ So, I then hooked up the MightyVac to the actuator and tried to vacuum the by-pass open. No dice....so it must be leaking, but I hook it up and it's working ok. SO....
Final test - Disconnect actuator, zip tie the by-pass open and plug the vac line (thereby eliminating the leaky part). Car still idles like poop and I get the same vac readings. Same odd miss. So I found a leaky part, but not my problem part.
Could the IAC be the culprit? Would it leak vacuum? Obviously it could cause an odd idle, but could it cause the car to go lean like that?
I plan on disconnecting the IAC and seeing the result. Also thinking about maybe disconnecting the TPS after that and seeing how it idles.
Any other ideas are welcome. Thanks