[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: testing an audi warmup regulator (CPR)?



>From: "Winggee" <winggee@hotmail.com>

>I just picked up a audi 5000 turbo CPR at the local yard. but how do you 
>test it. do i only hook up one vaccum line to it? how would i know if it 
>works or not? cause i dropped it (d'oh!) and don't know if it still works.

Well, you'd need a fuel pressure gauge, and a vacuum pump with gauge.

The FPG needs to have a 3-way junction on it. one to gauge, one always open 
and one with a valve to shut off flow. Not cheap, but TT sells these with 
Bosch fittings for a little over $200. It's _the_ way to test your fuel 
system though.

Disconnect the fuel line that goes to the CPR from the TOP of the fuel 
distributor. Connect the always open end of the "3-way junction" to the fuel 
distributor and connect the line to the CPR to the valved opening.

Close the valve, run the fuel pump. The gauge now reads the system pressure.
Open the valve, with the pump running. Now the gauge reads the control 
pressure.
Do the test with the CPR cold, hot, etc.

Now connect the vacuum pump to the CPR and bring it to about 16 in. HG. Read 
the control pressure and continue to read the pressure as you release the 
vacuum. The Control Pressure should increase. Don't know exact numbers, but 
for the standard CPR, my book says that at room temp (70 F) the control 
pressure should be at about 20-26 psi. When the heating element is 
connected, (after 1-2 min) the pressure should be 49-55 PSI.

I would think that at normal engine vacuum (16in HG?) the control pressure 
should be 49-55 PSI, and at no vacuum, it should be lower, but not as low as 
the cold enrichment pressure (20-26psi)

Lastly my book says to check the regulator diaphragm for leakage. Bring it 
to about 16in. HG, and time the return to atmospheric pressure. Any more 
than 3in HG drop in 15seconds indicates a busted diaphragm. Replace the 
regulator.

This last test might be all you need to do, as the vacuum diaphragm is 
probably the most fragile part in the unit.

HTH

Jonas
85 Scirocco 2.0
78 Scirocco 1.8
For direct reply: jonas@metabolex.com
http://www.geocities.com/scirocco2l8v

_________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.

Share information about yourself, create your own public profile at 
http://profiles.msn.com.


--
Email LIST problems to: scirocco-l-probs@scirocco.org. To unsubscibe send
"unsubscribe scirocco-l" in the message to majordomo@scirocco.org