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JFairman JFairman is offline
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Join Date: Jul 2006
Location: S. Florida
Posts: 7,274
"Did you try to lower the idle rpms with the rpm screw?"
No I didn't lower the idle speed screw because I knew something was wrong, I know 930 CIS as well as anyone now, and my idle speed is usually right where I want it (800rpms) and readjusting the idle speed around whatever went wrong makes no sense.

"Sound strage that the rpms can't be lower with it."
Thats because the cold start AAV vave is bypassing air around the throttle butterfly all the time as long as it isn't really heat soaked by a hot engine or getting 12 volts to heat up the bimetallic spring inside and close it... lowering the idle speed.

I have a DPDT switch hidden in the car that takes fused battery power in 2 seperate 12 gauge leads through the 2 seperate poles of the DPDT switch to keep the 2 seperate fuel pumps power leads isolated, one lead for each fuel pump. If you don't isolate the wires when doing that you'll permanently bridge the power supply lines from the relays to the fuel pumps together and thats not good for the 2 seperate fuel pump relays.
It bypasses the 2 fuel pump relays so I can turn both fuel pumps on without any of the multiple relays in the fuel pump cicuit used or involved.

When I noticed the weird rich AFR's and high idle speed I tried flipping that swtch and sure enough the AFR's slowly went to mormal and the idle speed dropped because now the rear fiuel pump and the WUR and AAV heater elements were getting power.
To make sure that was it I turned the switch back off and the AFR'S started slowly going richer and the idle speed at stop lights and signs creeped back up.

I had only been driving around 5 minutes when all this happened so the motor wasn't hot enough to heat soak the WUR or AAV yet and they completely rely on the heater elements to warm up after a cold start.

I put the DPDT fuel pump relay bypass switch in because my fuel pumps used to shut off randomly out of the blue every now and then and strand me on the side of the road or in the mioddle of an intersection until they would decide to work again...
That REALLY sucks and is very dangerous.
Turned out to be an intermittant plug/pin conection to the "speed relay" or factory rev limiter relay under the driver seat.
Old 06-19-2010, 09:52 AM
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