My car has been idling like shit and i have really low vacuum, and checked everything else and it seems that it can only be my ecu or my timing being off. I hooked my OBD11 tester in and evrything was good except for ignition advance. My fuel trims were fine, good % at WOT, but my ignition advance was going between -12 and -5 while idling. I want to know why is it jumping around and i though we the advance is not supposed to be in the negatives. I may be wrong, just trying to diagnose a problem. I think my timing is off, but dont know what the timing should be at at idle. Any help, thanks

have you messed with your timing belt recently.....timing marks off can cause this.

Terry

96 Eagle talon ESI
Star Stage II - Boost/oil/EGT gauges

97 Eclipse
Greddy header - Apexi N1 3" exhaust - SFMU/return line - Stage 2 6 puck Sprung hub MIBA clutch - Shortened shifter - Koni Yellows w/eibach prokit - Stillen Fr/Rr swaybars - ceramic intake - DEI Keyless entry alarm - Niche 17" Shoks

Waiting to be installed: Apexi AFC, HKS EVC IV, 450 Turbo injectors, GSX Front brakes (need rotors)

Mitchell on Demand copies available

No, i havent touched any of that. I just had my timing belt replaced when the shop fixed my bent valves. The belt still looks brand new, but i think the timing was off a mark or something. I have no clue, it may have been off when installed. I wish i knew, but i am only gonna check the ecu and timing. After that, i am so lost as to what could cause this low vac and rough idle.

low vac and idle are text book products of the timing off on the cams...did the car ever run right after the belt was replaced? I would pull the cover and double check.

Terry

96 Eagle talon ESI
Star Stage II - Boost/oil/EGT gauges

97 Eclipse
Greddy header - Apexi N1 3" exhaust - SFMU/return line - Stage 2 6 puck Sprung hub MIBA clutch - Shortened shifter - Koni Yellows w/eibach prokit - Stillen Fr/Rr swaybars - ceramic intake - DEI Keyless entry alarm - Niche 17" Shoks

Waiting to be installed: Apexi AFC, HKS EVC IV, 450 Turbo injectors, GSX Front brakes (need rotors)

Mitchell on Demand copies available

How do i know if the cams are off timing? I should check the timing on the gears, right. I just want to understand your reply so i know what to check. My camshaft position sensor wouldnt have anything to do with that since it is on the side of the head on the exhaust cam. Just wondering. I appreciate the help, thanks. I will check tomorrow for those things.

well you need to pull off the timing cover and align the marks on the crank/oil pump. then check the marks on the cam gears. its a pain to do but the best way. I highly doubt your ECU or cam sensor is the culprit. If the intake cam is off by a tooth or two you will develope the low vac and lopey idle. It would be like having a very large overlap on the intake-exhaust cam lobes.

Terry

96 Eagle talon ESI
Star Stage II - Boost/oil/EGT gauges

97 Eclipse
Greddy header - Apexi N1 3" exhaust - SFMU/return line - Stage 2 6 puck Sprung hub MIBA clutch - Shortened shifter - Koni Yellows w/eibach prokit - Stillen Fr/Rr swaybars - ceramic intake - DEI Keyless entry alarm - Niche 17" Shoks

Waiting to be installed: Apexi AFC, HKS EVC IV, 450 Turbo injectors, GSX Front brakes (need rotors)

Mitchell on Demand copies available

Cam timing is off. I know exactly what symtoms you are describing. Whoever did your timing belt, didn't put the belt on right with the timing marks..

Thanks, i will have it fixed monday. I was leaning towards that but i feel much better knowing i got second opinions from you guys who know more about our cars. Points for both of you.