wicks

Hi, wondering if a 3.3 Turbo Control Unit will work in a 3.6, just for testing purposes? Also the Multi-function control unit.

3.6 units are:
Turbo Control "Enrichment" unit: 965-618-131-02
Multifunction unit: 965-618-130-01

3.3 units are:
Turbo Control "Enrichment" unit: 965-618-131-00
Multifunction unit: 965-618-130-00

I can only find reference to difference in the TCU from Adrien's booklet:
Oxygen sensor control.
The oxygen sensor control unit is mounted underneath the left hand seat. There are two different part numbers used for the 3.3 litre engine,
ROW 965 618 103 00
USA 965 618 103 01
The Turbo 3.6 system uses a modified oxygen sensor control unit, which processes the 0° (idle) throttle switch position. This is done to improve pickup of the engine in the low load range. Oxygen sensor speed is only doubled if the throttle opening angle exceeds 7°.

peterpullin

Metal Guru

Your first mistake was reading Streather's coffee table book. It cannot by any stretch be called a technical reference.
The Enrichment unit is the Lambda computer.
The Turbo Control Unit is under the drivers' seat. It's 4 inches by 2.5 inches by 1 inch. The Enrichment unit is 5x that size.
The Turbo Control unit is a safety relay. It won't enable fuel pump and ignition operation until it gets a signal from the flywheel hall effect sensor.
If it was bad, your car wouldn't run at all.
Go put your WUR back on the car and test it to the procedure.

wicks

OK thanks for clearing that up. Reading a thousand words on this stuff can get quite confusing, and listening to so many voices who may or may not know what they're talking about. I was unable to get a control pressure reading on the test, so I should debug that. As if the WUR was completely stuck and would not open at all to release any system pressure back to tank. This is why I want to try to blow air pressure through the WUR or something to see if it will open. Maybe I should have a look inside of it while it's sitting on the kitchen counter. Also should I do the freezer test with it? I'm worried the bi-metal strip or a spring could break if I take it to extreme cold. My subzero is set to 0 degree freezer.

wicks

Observing the WUR - it actually lets air pass from 40 PSI all the way down to about 25 PSI then the flow gets very small. Completely stops airflow by 20 psi. Seemed like it was completely closed before, but I didn't pay a lot of attention last time I tried to blow air through it. And maybe it was warmer.

Igooz

FWIW: If you need one, I have a USA 965 618 103 01 brand new that I bought a couple of year ago to run my 1987 930 3.3 through emissions. It was in the car about 25miles worth.

wicks

Paul - Your advice was right on. I worked through the issues around fuel pressure and have found control pressure finally, by bypassing the FPR return to tank line from the WUR. So, I seem to have a blockage of fuel return to tank. I will re-check the FPR in the fuel head next, but wondering if anyone has a 1,2,3 on what is the most common cause of fuel return to tank being blocked.

Metal Guru

Congratulations on your discovery. You are now a CIS expert
I'm trying to remember where that regulator is. It's also possible that I didn't know it was there in the first place.
I'll have to study my diagrams in the manual tonight...

wicks

It's just screwed into the FD. With the little shims to set system pressure. What a saga - but finally all is well and luckily my (possibly unnecessary) rebuild of the FD didn't screw anything up.