replaced injectors and pressure regulator, now '90 90 7a is idling funny
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From: Ashland Oregon
replaced injectors and pressure regulator, now '90 90 7a is idling funny
So four of the Hitachi injectors broke as I took them out which makes me think they were old and probably clogged. The FPR Was from an AAN so it was also contributing to a leaner mixture.
Once I installed the Aero adjustable FPR, and figured out how to set the pressure properly, the car ran like it had been given a second chance at life. I mean it was amazing.
Unfortunately the idle remains high once the car has warmed up, and there is an odd turbulence when I release the throttle now. There are also a few instances of the idle wandering up and down between 1k and 1.4k, which makes me think the ISV is causing the problems. It is Hitachi style.
Took the ISV apart and there was definitely some gunk in the airways, and on the articulating end of the detachable electronic piece. I sprayed some cleaner in there and then a few drops of oil where I thought it would lubricate the spring. It made the problem worse.
Could the ISV have gotten all gunked up from constantly having to adjust because of the lean mixture?
Has anybody disassembled the spring/valve assembly by cutting off the bent metal cap opposite the electric connector end, as instructed by 20v.org?
Also I wonder if the idle adjustment screw has ever been messed with, to accommodate for incorrect parts?
I can feel a bit of vacuum from the idle screw hole, is this normal?
Thanks for any help
Once I installed the Aero adjustable FPR, and figured out how to set the pressure properly, the car ran like it had been given a second chance at life. I mean it was amazing.
Unfortunately the idle remains high once the car has warmed up, and there is an odd turbulence when I release the throttle now. There are also a few instances of the idle wandering up and down between 1k and 1.4k, which makes me think the ISV is causing the problems. It is Hitachi style.
Took the ISV apart and there was definitely some gunk in the airways, and on the articulating end of the detachable electronic piece. I sprayed some cleaner in there and then a few drops of oil where I thought it would lubricate the spring. It made the problem worse.
Could the ISV have gotten all gunked up from constantly having to adjust because of the lean mixture?
Has anybody disassembled the spring/valve assembly by cutting off the bent metal cap opposite the electric connector end, as instructed by 20v.org?
Also I wonder if the idle adjustment screw has ever been messed with, to accommodate for incorrect parts?
I can feel a bit of vacuum from the idle screw hole, is this normal?
Thanks for any help
Thread Starter
AudiWorld Member
Joined: Feb 2012
Posts: 125
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From: Ashland Oregon
This morning I also noticed the vacuum hoses around the isv are cracked and suspect. I imagine these can be replaced with something found at the parts store?
Idle is hovering around 1100 and still wavers a little bit. If I disconnect the electrical connector, or pinch the hose between the manifold and isv, the idle drops a little. When the isv is dosconnected the idle stays at about 900-100
Idle is hovering around 1100 and still wavers a little bit. If I disconnect the electrical connector, or pinch the hose between the manifold and isv, the idle drops a little. When the isv is dosconnected the idle stays at about 900-100
Last edited by Solid20vq; Mar 25, 2013 at 08:35 AM.
Thread Starter
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Joined: Feb 2012
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From: Ashland Oregon
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Heh, nice job. My idle was high for a good 15 minutes and a few drive cycles and slowly came down to normalish. Your experience sounds like mine after putting new injectors in - a new lease on life. The engine is incredibly smooth, and pulls without bucking from below idle speed. Well done!
DougM
DougM
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