dfinnegan

Is this the correct part number for the CHT sensor for a 91 C4?

I've searched the PET5 data, but couldn't find this sensor.

CHT Sensor
Porsche part # 930 606 013 02

Thanks,
Dave

Pingo

Yes, thats the correct part#. See illustration 103-00 (MG=1, SG=3) PET.

JasonAndreas

Dave,
When you checked the CHT sensor what were the results? And if you are tossing your old, busted sensor could I possibly buy it?

dfinnegan

Jason,

If I toss my old sensor you can have it. The folks on this list earn their keep every day and you, for one, certainly deserve more than an old busted sensor for the time and effort you provide here.

That said, I haven't yet tested the sensor. I was traveling on business all last week and only had time enough to botch my new oxygen sensor installation this weekend!

I've been without my car for a week now and will be without for a second week due to the current problems. Given that it's my daily driver and I have to travel for work this is becoming a real hardship for me.

With that in mind I've begun thinking about what I need to do to get it back on the road. This may include ordering a cht sensor even though I've not yet determined that to be the problem. I expect the oxygen sensor to cure my stalling problem, but, as you can tell, I'm not one hundred percent certain. Thus the need for a backup plan.

At present, I have the catalytic converter off the car and I've sent it, along with the, now damaged, new oxygen sensor off with my father in-law as he has access to a machine shop. I'm hoping the machine shop can clean up the slightly fouled threads in the catalytic converter. I really don't want to spring for a new one of these.

I'm also hoping that the machine shop can clean up the threads on the new oxygen sensor and get that installed into the catalytic converter. I buggered the first one, or two, threads trying to get it installed. I'm not expecting them to be able to fix this, though, and so I'm planning on ordering a new oxygen sensor and will likely order a new cht sensor, too.

I figure the cat threads will get cleaned up and one of the new o2 sensors will go in. If that doesn't solve the stalling problem then I'll change out the cht sensor.

The diagnostic codes did call for this. By rights I should have done this first. Of course, I now wish I had done this first! However, a great deal of information from this site, along with the recent experience of driving in driving rain made me believe the o2 sensor was the culpirt. I'll know soon enough.

I'll keep you posted on my results and forward along the old sensor if I end up replacing it.

Also, if I may, another question. Do I need to replace the squared, four bolt metal gasket between the exhaust manifold and the catalytic converter when I reassemble it?

The gasket seems to be in good shape, but perhaps it's already been compressed too much and must be replaced. I just don't know.

Same question for the donut shaped piece between the catalytic converter and the primary cross muffler in the rear bumper; actually a cup pipe on my car. Does that need to be changed. It seems perfrectly fine to me, but I thought I'd ask.

Thanks,
Dave

JasonAndreas

On the bottom of the left hand seat, right around the DME control unit you'll find a little white 3-pin jumper plug (image below). If you swap the wire from the center to the free outer pin than your car will ignore the O2 sensor.



Do you own a multimeter or an ohmmeter? If so, just check the level of resistance between the two pins on the white connector in the left rear of the engine bay. If you don't own a multimeter you could connect a wire between the two pins and the DME control unit will/should think that the engine is at operating temperature. So if the car is running okay while at operating temperature than you know the CHT sensor is the problem.


I was told to always replace crushable metal gaskets, never reuse. Part #964-111-198-00 was around $3-5 (from Sunset) last time I did a valve adjustment so I would just replace it.

Those you can reuse.