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mooney265 mooney265 is offline
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Join Date: Sep 2008
Location: New Orleans
Posts: 1,365
Warm CP begins to fall at T+9 Min???

I have a BL Adjustable WUR with RPM switch. Have had it for 4-mos. Adjusted it 3-times in the past.

Recently, I noticed the car's AFR's were fluctuating towards a rich condition, so I thought I'd re-verify my last settings done on 9/18. They were:

System Pressure: 6 BAR
Cold: 2.6 BAR
Warm: 3.8 BAR
Enrich: 2.5 BAR - - that was running a little rich [below 10 AFR] using a 4,800 rpm pill - - so, was going to adjust today…

So, today I hooked up the gauges and saw the following:
System: 6 BAR - - Checked OK
Cold: 2.6 BAR [Time + 0] - - Checked OK
Warm: 3.8 BAR [Time + 2 min] - - Checked OK
Enrich: 2.5 BAR [Time + 3 min] - - or, a 1.3 BAR drop for enrichment - - Checked OK

My plan was to adjust the enrichment up to 2.9 BAR [or, 0.9 BAR drop]. As soon as I was completed adjusting the enrichment up to 2.9 BAR, I noticed my warm control pressure beginning to drop on its own!

This pressure drop began at [Time + 9 min] and continued for the next 6-minutes until the pressure held at 2.9 BAR. So, the pressure is slowing dropping 0.9 BAR over a 6-minute period. This pressure drop begins at Time + 9-minutes from "cold condition." Once the warm pressure leveled off at 2.9 BAR, I tested the enrichment pressure and it was 2.0 BAR [or, 0.9 BAR below warm pressure]. So, the enrichment was still working - - just followed the warm pressure on its way down…

I was able to replicate this throughout the morning a total of 3 times. I never started the car... What's going on with the WUR??

By the way: I checked the voltages at the WUR throughout the process: Steady 11.70 Volts with a 10-amp charger hooked to the battery and running constantly. Voltage at the battery stayed a constant 12.25 volts.

Any ideas????
LIVN80S - - Red '79 Porsche 930 Steel Slant Nose Conversion [in 1987] w. 46k miles 3.3L; 964 Cams; K27HF @ 1.0 BAR, with Garrettson Intercooler; Rarly Zork; CIS Flowtech Fuel Head & BL-WUR.
Old 10-24-2009, 08:56 AM
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