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1988 Chevy Sprint

I Have this Sprint and I can't get it to lean out the mixer control selenoid unless I ground the blue wire with red stripe which the computer is supposed to ground. At first the selenoid wasn't working so I installed another one that does work. I watch a volt meter connected to the o2 sensor to see if the computer is trying to control the ground and it doesn't. Do I need a speed sensor signal for the feedback to work? I do have some high ground resistance in a black wire with a green stripe, .99 MV, does anyone know if this is a computer ground? It runs lean at idle .230 MV, and real rich at 3000 rpm 1 volt and higher,no O2 switching at all. Has anybody ran into this no feedback problem? Any and all help and any idea somebody might have has to why the feedback system is not working right will be greatly appreciated.

Thanks, Bill

Reply to
billscorpio
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On an 88 I would make sure the body has a really good ground path to the battery. When the ground connections get corroded or go rotten like some mesh straps do, the computer can loose it's ground tag and things like you describe can happen.

I live in the rust belt and see it all the time on various vehicles.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

Was the vehicle running poorly, any codes? How old is the 02 sensor?

I've seen brand new, one wire 02 sensors, that would not switch at idle, not getting hot enough. I would go off idle, a few rpms, and the thing would start switching like crazy. If it won't switch at lower rpms, try to richen the system, see if the 02 sensor voltage changes.

At higher rpms, some systems will go into open loop. The computer won't pay any attention to the 02 sensor.

The last feedback carb I worked on, I hooked a dwell meter to the M/C solenoid connector, to see what was going on.

I can't tell by your post, what tests you've tried.

Reply to
jdl

Reply to
billscorpio

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