Belpor

Hi,

I'll answer some posts:

Theiceman: I measurred the CO at the exhaust and adjusted the idle at 900 rpm with the O2 sensor disconnected. Set the CO later at 2,5.
I was happy to have the tester so I did that first

Peter Zimmerman: I'll do the CO adjusting again as you discribed and let you know.

Ninemaster: injector testing is a good advice. I'll do the teseting after the CO and fuelpressure test.

Rusnak: Sounds like thats the problem to me. Olly the car runs great sometimes and seems to get enough fuel. I'll do the "easy stuff" after the CO and fuelpressure test because I want to know if thats goog.

Thanks for all of the replies. I'll let you know!

Belpor

Hi,

I wanted to measure the CO at the test port at the front of the cat. I can't find it..

I don't see any port, not even one welded

Reiver

Not a stock Cat, aftermarket.

rusnak

Yeah, I see several options. Either install a test port or an O2 sensor on the cat, or buy a test pipe with one already installed, and swap out the cat. Of course, you don't really need a second port if you buy a test pipe, but you will if you are using a wideband O2 sensor type of AFR tester. And those need to be installed fairly well upstream of the tailpipe.

theiceman

Could he not take out the o2 sensor and use that port. I thought I read somewhere you are supposed to jumper something and take the o2 senor out. Or maybe I just dreamed that

Peter Zimmermann

Yeah, replace the cat with an o.e. unit ($$$$$), or take out the oxs and rig something that will connect to the CO machine. Removing the sensor will not make a difference, because it must be disconnected for the CO test/adjustment.

Man, that cat is awfully small, wonder if it's restricting exhaust flow?

Belpor

Pfffff%@#^%$#^%$@@^^$

Was my first reaction. But I checked and adjustedthe CO before the cat!
When testing the car after adjusting the car is accelrating really fine! Only in low rpm the is hesitating a little. Also when I let throttle the engine is rumbuling a little. I will check the car when its cold warming up and warm again and let you now.

Your input was really helpfull

Belpor

Been out for a few days (needed that after this adventure).
Here are my resluts after setting the CO correctly before the cat:

Fuel pressure meter connected to the warm up valve and mixture control unit. Let the air out.

Cold control pressure, ignition switch on:
Engine cold: 1,8 bar
Engine runs: 1 bar
Engine off: 1,8

Warm control pressure: Porsche workshop manual (p180) says could also be cold if you give the warm up valve directly 12v. Engine ingnition switch on and 12v on the warm up valve:
Fuelpressure 2,8 bar and very slow rising to 4,0 bar.
According to the manual we should test with opening throttle half and full. We did that but no effect! Pressure stays at 4,0 bar
We also did the test without 12v on the warm up valve, also no effect!

If nessecary we can do a test with a warm engine. Let me know!~
Or can somebody allready say if the warm up valve is broken?

Belpor

Hey guys,

No more suggestions? Any other professionals here on the forum?