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JFairman JFairman is offline
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Join Date: Jul 2006
Location: S. Florida
Posts: 7,289
You check the voltage the narrow band lambda O2 sensor is generating at the wires coming from it. Thats easy with a generic low cost 2 wire O2 sensor that has no heater element in it but the one in your car has a heater element to get it up to operating temp quickly so you have to figure out which 2 wires to check.

When you say the idle is hunting, do you mean oscillating up and down steadily with dark colored rich exhaust full of stinky unburnt hydrocarbons ?
Mechanical air flow meter fuel injection like CIS and L-jetronic are both good at that when running too rich at idle.

Do you need the lambda system to pass emission testing in Texas?

If not, do your car and yourself a huge favor and get rid of it.
Then adjust the 6 fuel head allen head final fuel trim screws next to the injector line banjo's to compensate for fixed lower chamber pressure without the pulse valve returning that lower chamber control pressure fuel in varying amounts to the fuel tank. Thats tricky if you've never done it and takes an injector flow test to get it right so it's best to send the fuel head to to CIS flowtech and have Larry do it.

The black relay next to the yellow relay on an '87 supplies the heater element in the O2 sensor with 12 volts.
Old 01-23-2013, 04:37 PM
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