help me diagnose plz!
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ive got a slightly rough idle..the car bogs a little bit on acceleration, but once it hits 1k rpm its fine. i thought it might be a vacuum leak of some kind, but i've sprayed carb cleaner all around the intake and it didnt idle up
somebody help me diagnose this problem.
somebody help me diagnose this problem.
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haha no, nobody slipped a big cam...dont think its the plugs/wires/coil/opti...all has been replaced about 4 months ago
and..if it were those things, wouldnt the problem occur at any RPM?
and..if it were those things, wouldnt the problem occur at any RPM?
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tried to get oreilly's to scan it today but they dont do OBDI anymore...O2's are prob pretty old..i kept the ones out of my manifolds when i put my headers in...i'm sure they were the factory ones
i guess i need to find someone with an obd1 scanner
i guess i need to find someone with an obd1 scanner
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I'm bringing this back to the top for him, we noticed an issue with the voltage meter -whenever this idle problem happens the voltage meter dips to near 10-11 and doesn't really move past 13 even during acceleration. Looked into the alternator and thought the regulator would be going out, replaced that and it still has the same issue.
It only has the idle issue in gear, it's a stock A4. The MAF has been cleaned, the IAC tested fine at 60, plugs/wires/opti/coil all have spark and there isn't a miss at any other rpm, don't know if the fuel system has been checked yet but - like he said- it doesn't happen any other time but idle.
Unplugged the 02 sensors one at a time while running and it still does it, also unplugged the MAF and same problem so it seems like this doesn't have to do with electronics. It does it in both open and closed loop.
Any suggestions? This may be unrelated but in the other thread he found a little bit of water in the lifter valley after he pulled the intake manifold. That does point to a blown headgasket, but it could have just been some condensation. Looking for any other ideas b/c I am fresh out.
It only has the idle issue in gear, it's a stock A4. The MAF has been cleaned, the IAC tested fine at 60, plugs/wires/opti/coil all have spark and there isn't a miss at any other rpm, don't know if the fuel system has been checked yet but - like he said- it doesn't happen any other time but idle.
Unplugged the 02 sensors one at a time while running and it still does it, also unplugged the MAF and same problem so it seems like this doesn't have to do with electronics. It does it in both open and closed loop.
Any suggestions? This may be unrelated but in the other thread he found a little bit of water in the lifter valley after he pulled the intake manifold. That does point to a blown headgasket, but it could have just been some condensation. Looking for any other ideas b/c I am fresh out.
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I'm bringing this back to the top for him, we noticed an issue with the voltage meter -whenever this idle problem happens the voltage meter dips to near 10-11 and doesn't really move past 13 even during acceleration. Looked into the alternator and thought the regulator would be going out, replaced that and it still has the same issue.
It only has the idle issue in gear, it's a stock A4. The MAF has been cleaned, the IAC tested fine at 60, plugs/wires/opti/coil all have spark and there isn't a miss at any other rpm, don't know if the fuel system has been checked yet but - like he said- it doesn't happen any other time but idle.
Unplugged the 02 sensors one at a time while running and it still does it, also unplugged the MAF and same problem so it seems like this doesn't have to do with electronics. It does it in both open and closed loop.
Any suggestions? This may be unrelated but in the other thread he found a little bit of water in the lifter valley after he pulled the intake manifold. That does point to a blown headgasket, but it could have just been some condensation. Looking for any other ideas b/c I am fresh out.
It only has the idle issue in gear, it's a stock A4. The MAF has been cleaned, the IAC tested fine at 60, plugs/wires/opti/coil all have spark and there isn't a miss at any other rpm, don't know if the fuel system has been checked yet but - like he said- it doesn't happen any other time but idle.
Unplugged the 02 sensors one at a time while running and it still does it, also unplugged the MAF and same problem so it seems like this doesn't have to do with electronics. It does it in both open and closed loop.
Any suggestions? This may be unrelated but in the other thread he found a little bit of water in the lifter valley after he pulled the intake manifold. That does point to a blown headgasket, but it could have just been some condensation. Looking for any other ideas b/c I am fresh out.
For some reason my voltage has always dipped low. It will read almost 13 on start up and it will sit at around 11 once warm and stay there. It's done that for 5 years now and I've never had an issue. I always thought it was just an inaccurate gauge. I've gone through a different alt, battery, had the battery harness off a few times, several starters, and no change...no problems either.
If you suspect a blown head gasket, have you checked the oil for water or checked the water for oil? Any white smoke comming from the exhaust?
Also since you are running down the list of things to test, try to pick up a vacuum gauge and see what vacuum you are pulling at idle. Worth a shot I guess.
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the iac was 60ohms resistance off the car. shbox says it should be between 40 and 80. i cleaned it anyways just for the heck of it.
today we tried adjusting the throttle idle screw (yah i know this isnt the correct way to set your idle speed) and instead of the idle dipping to 490 or so..it only dipped to 525..still had the same problem though...if you just sit there in gear it will idle rougher and rougher the longer you let it sit there..oil pressure will drop as well as volts.
keep in mind this started happing when i replaced the intake gasket...if its not related to that then it is just one HUGE coincidence.
i'll try picking up a vacuum gage...can i hook it up at any vacuum on the intake? what should it read at idle?
please help guys..i'm running outta patience and this is my DD
today we tried adjusting the throttle idle screw (yah i know this isnt the correct way to set your idle speed) and instead of the idle dipping to 490 or so..it only dipped to 525..still had the same problem though...if you just sit there in gear it will idle rougher and rougher the longer you let it sit there..oil pressure will drop as well as volts.
keep in mind this started happing when i replaced the intake gasket...if its not related to that then it is just one HUGE coincidence.
i'll try picking up a vacuum gage...can i hook it up at any vacuum on the intake? what should it read at idle?
please help guys..i'm running outta patience and this is my DD
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oh yah..just fyi..i have already tried spraying around the intake to check for intake leaks...never idled up.
also..one other piece of info..on my EGR..i still have the EGR solenoid hooked up (just to keep from throwing a code)..but i have both vacuum inlets on it capped off...i also have the EGR pipe still on the manifold...it is capped off of course....and the EGR valve is still on the manifold..with a vacuum cap on it as well...dunno if EGR could be the culprit here, but its the only thing i can think of that changed when i took the intake off
i've tried hooking all the EGR stuff back up but it still did it....is it possible the diaphragm in the valve is stuck open? would this even matter if everything was capped off?
also..one other piece of info..on my EGR..i still have the EGR solenoid hooked up (just to keep from throwing a code)..but i have both vacuum inlets on it capped off...i also have the EGR pipe still on the manifold...it is capped off of course....and the EGR valve is still on the manifold..with a vacuum cap on it as well...dunno if EGR could be the culprit here, but its the only thing i can think of that changed when i took the intake off
i've tried hooking all the EGR stuff back up but it still did it....is it possible the diaphragm in the valve is stuck open? would this even matter if everything was capped off?
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also..when i started the car for the first time after putting the intake back on...i had left the coolant hose unhooked from the TB...so some coolant got on the opti...its vented and it runs fine other than idle...so i pretty much ruled this out as a culprit
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here's a link to camaroforums of the EXACT problem i'm having http://camaroforums.com/forum/showthread.php?t=11482
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Lol that's alot of also's you're just trying to get up your post count aren't you ![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
Vacuum should read at least 15 if not 17 and yes you can put it on any vacuum port on the intake. I'd use the EGR one that you have capped.
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Vacuum should read at least 15 if not 17 and yes you can put it on any vacuum port on the intake. I'd use the EGR one that you have capped.
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is it possible i could have done something to the fuel pressure regulator when I was moving the fuel rail/injectors harness around while getting the intake manifold out?
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got another peice of info that might be related to this...last night after a long drive, i pulled in to buy gas...when i took the gas cap off there was a loud, long hissing...more than normal..like excess pressure was built up in the fuel system...could this be caused by a faulty FPR? could it be related to my idle issue?
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got another peice of info that might be related to this...last night after a long drive, i pulled in to buy gas...when i took the gas cap off there was a loud, long hissing...more than normal..like excess pressure was built up in the fuel system...could this be caused by a faulty FPR? could it be related to my idle issue?