Rough idle
04-17-2016, 11:54 PM
#1
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Rough idle
Car is having a hard time starting. I checked cylinder roughness and all is good. Changed the spark plugs just in case. But once its on and warm it would idle at 2000rpms and the drop below 1000 and the car would start to die. Before it dies my afr gauge reads at 9.2. I checked for boost leaks through the fmic and everything is fine. Checked thw turbo and still looks good with no play. What do I do????
04-18-2016, 08:12 AM
#3
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I have a crawford AOS when i took the pipes off for the fmic it was clean all through. But when you go to gove it gas thats when it drops from 14 to 9.2 on the afr. I think its an air leak somwhere but cant find it cause i heard a pop like a balloon go off when i was driving. Its not a head gasket and cylinders still have compression.
04-18-2016, 12:05 PM
#6
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04-21-2016, 09:17 PM
#7
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Join Date: Jul 2013
Location: Oahu
Posts: 44
Car Info: 2002 wrx wagon
Car is having a hard time starting. I checked cylinder roughness and all is good. Changed the spark plugs just in case. But once its on and warm it would idle at 2000rpms and the drop below 1000 and the car would start to die. Before it dies my afr gauge reads at 9.2. I checked for boost leaks through the fmic and everything is fine. Checked thw turbo and still looks good with no play. What do I do????
04-23-2016, 09:16 AM
#8
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04-23-2016, 11:59 PM
#9
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Join Date: Jul 2013
Location: Oahu
Posts: 44
Car Info: 2002 wrx wagon
What about the IACV? My car had similar issues. I cleaned it and my car idled perfect after. Its happened to me twice. The last time I cleaned it and spreyed a little wd40 in it and never had problems with it since.
04-27-2016, 11:20 AM
#10
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Car Info: 51E LHD V7 STI (2.0)
do you get a CEL?
9.2 AFR is more RICH than 14.7 AFR. LEAN would be on the upper scale like 18-20 AFR.
since it's an 08 you don't have an IACV since its drive by wire
only the drive by cable guys have IACV
if the car is starting good it's normal for the idle to be high at or just before 2k. eventually it should be dropping and eventually idle out at either 7-900RPM with AC on and around 5-700 RPM without AC.
On a DBC (drive by cable) car if the RPM stays high continuously you will get a CEL.
what have you changed assuming it's not stock.
if you had vacuum leak you'd see AFR more lean like 18-20 range as i've mentioned. where and how are you taking your AFR readings? is the gauge a wide band or a narrow band gauge? there is a difference.
9.2 AFR is more RICH than 14.7 AFR. LEAN would be on the upper scale like 18-20 AFR.
since it's an 08 you don't have an IACV since its drive by wire
only the drive by cable guys have IACV
if the car is starting good it's normal for the idle to be high at or just before 2k. eventually it should be dropping and eventually idle out at either 7-900RPM with AC on and around 5-700 RPM without AC.
On a DBC (drive by cable) car if the RPM stays high continuously you will get a CEL.
what have you changed assuming it's not stock.
if you had vacuum leak you'd see AFR more lean like 18-20 range as i've mentioned. where and how are you taking your AFR readings? is the gauge a wide band or a narrow band gauge? there is a difference.
Last edited by iNfEk; 04-27-2016 at 11:24 AM.
04-27-2016, 01:19 PM
#11
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Thread Starter
do you get a CEL?
9.2 AFR is more RICH than 14.7 AFR. LEAN would be on the upper scale like 18-20 AFR.
since it's an 08 you don't have an IACV since its drive by wire
only the drive by cable guys have IACV
if the car is starting good it's normal for the idle to be high at or just before 2k. eventually it should be dropping and eventually idle out at either 7-900RPM with AC on and around 5-700 RPM without AC.
On a DBC (drive by cable) car if the RPM stays high continuously you will get a CEL.
what have you changed assuming it's not stock.
if you had vacuum leak you'd see AFR more lean like 18-20 range as i've mentioned. where and how are you taking your AFR readings? is the gauge a wide band or a narrow band gauge? there is a difference.
9.2 AFR is more RICH than 14.7 AFR. LEAN would be on the upper scale like 18-20 AFR.
since it's an 08 you don't have an IACV since its drive by wire
only the drive by cable guys have IACV
if the car is starting good it's normal for the idle to be high at or just before 2k. eventually it should be dropping and eventually idle out at either 7-900RPM with AC on and around 5-700 RPM without AC.
On a DBC (drive by cable) car if the RPM stays high continuously you will get a CEL.
what have you changed assuming it's not stock.
if you had vacuum leak you'd see AFR more lean like 18-20 range as i've mentioned. where and how are you taking your AFR readings? is the gauge a wide band or a narrow band gauge? there is a difference.
04-27-2016, 01:48 PM
#12
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Car Info: 51E LHD V7 STI (2.0)
hard inlet can leak right after the turbo to coupler connection and or coupler to inlet. again, if you've got a wb02 installed it'll read more lean and it'll indicate a leak. you can try to pressurize the intake system and spray soapy water to verify if you've got a vacuum leak or not. further, what happened to your alternator? you can check o'riley or similar shop for a replacement alternator. i believe there's also alternator repair shops on island as well. cannot think of them right now. in fact, i have my original 14 year old alternator in my car now and it's still going. alternator will only affect your charging system anyway. i doubt a CEL would be thrown or affect your idle either. since the battery is new thats why your car is starting since the starter is good as well. again not related to your idling issue.
04-27-2016, 02:11 PM
#13
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Thread Starter
hard inlet can leak right after the turbo to coupler connection and or coupler to inlet. again, if you've got a wb02 installed it'll read more lean and it'll indicate a leak. you can try to pressurize the intake system and spray soapy water to verify if you've got a vacuum leak or not. further, what happened to your alternator? you can check o'riley or similar shop for a replacement alternator. i believe there's also alternator repair shops on island as well. cannot think of them right now. in fact, i have my original 14 year old alternator in my car now and it's still going. alternator will only affect your charging system anyway. i doubt a CEL would be thrown or affect your idle either. since the battery is new thats why your car is starting since the starter is good as well. again not related to your idling issue.
04-27-2016, 02:26 PM
#14
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Join Date: Nov 2002
Location: Boostin' troubles away - 4EAT Memories 12.87@103.2
Posts: 10,454
Car Info: 51E LHD V7 STI (2.0)
An oem replacement is a lot cheaper than oem Subaru one.
04-27-2016, 04:57 PM
#15
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Location: Kahaluu, Oahu
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Car Info: 07 Sti
Starters and alternators - they can rewind your stock one for $150 probably your best bet.
Why would you want to get a higher amp alternator? Are you running a gigantic sound system in the car? That's a hell of a lot of draw....
Why would you want to get a higher amp alternator? Are you running a gigantic sound system in the car? That's a hell of a lot of draw....