SAAB Miata won't idle
#1
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SAAB Miata won't idle
Going with the assumption that everyone doesn't read worklogs so re-posted here. After starting the SAAB a time or two last night it won't idle. Runs fine, revs fine, will idle around 1000rpm if I keep my foot on the gas but dies as soon as I let that off. No old gas in the car. Tank was removed and emptied and lines were empty as well.
I may just say "good enough" for now and deal with it after MS and injectors but it used to run and idle fine two years ago. My only concern was to start with a Perfectly Running car before going to the MS. A couple of things that are different from the original car that may be affecting it are
Idle air port on the TB is just wide open now. Didn't think this would be it as it would be wide open to the intake but who knows.
Extended wires on MAF so I didn't have to cut a hole in the inner fender for something that was temporary. Used old three wire trailer wire which was kind of suspect.
Factory O2 was cut, lengthened and installed in WB O2 port 36" back.
Exhaust is passing through turbo with wastegate wired open
The "two o-ring under injector to replace missing insulator" shouldn't affect anything but it's different. It seemed to run fine for the trip home when I bought it with no insulator. Injector must have been just pushed into the rail.
Possibly missing or improper grounding somewhere. I only have one engine ground now to the subframe. Need another for sure for head to unibody.
I may just say "good enough" for now and deal with it after MS and injectors but it used to run and idle fine two years ago. My only concern was to start with a Perfectly Running car before going to the MS. A couple of things that are different from the original car that may be affecting it are
Idle air port on the TB is just wide open now. Didn't think this would be it as it would be wide open to the intake but who knows.
Extended wires on MAF so I didn't have to cut a hole in the inner fender for something that was temporary. Used old three wire trailer wire which was kind of suspect.
Factory O2 was cut, lengthened and installed in WB O2 port 36" back.
Exhaust is passing through turbo with wastegate wired open
The "two o-ring under injector to replace missing insulator" shouldn't affect anything but it's different. It seemed to run fine for the trip home when I bought it with no insulator. Injector must have been just pushed into the rail.
Possibly missing or improper grounding somewhere. I only have one engine ground now to the subframe. Need another for sure for head to unibody.
#7
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So when using MAP and no MAF and using MS I can just run this port with a filter?
#12
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We either block it off (I don't think a lot of people do this) with a plate and deal with the crappy cold idle, and otherwise tune with the idle screw; OR, plumb it into the intake. You can see the ~1" pipe on most intercooler routings.
#13
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At first I didn't see plumbing into the intake as working due to positive pressure but after I thought about it, it's only needed when at idle which would put the IM in vacuum, no different than if it was in the intake tube. When pressurized it wouldn't be needed as it isn't at idle unless you are running a GT15 turbo, lol.
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