Bill S.

Is anyone getting misfire codes (check engine light) on their Ruf Turbo R at high RPM (e.g., 6,800) under full load?

I'm getting these codes:

P0300 Random/Multiple Cylinder Misfire Detection
P0306 Cylinder 6 Misfire Detection
P0303 Cylinder 3 Misfire Detection

kmy

Bill,

When is the last time you changed your plugs?

Kevin

Bill S.

The plugs are new.

Kevin

Are you running pump 91?

If you are running better fuel it could be your knock sensors. Did you replace them after your recent topend?

Do you have anyway to datalog?

Bill S.

I was running better fuel. I didn't replace the knock sensors. Would they cause these errors? What happens to them?

I could run a data log. What do you recommend?

Kevin

Failing knock sensors will give you false misfires.

Severe detonation will also produce the same results.

Your heads were milled. This increases compression. How many times have the heads been machined.

Bill S.

Interesting. I'll have them check the sensors. I don't think I'm getting severe detonation, but I do hear one or two "tick" or "ping" sounds near 6,500 under load, so maybe that's related. I've also heard that before the rebuild.

I'm not sure the heads were milled, but I'll check that also. This is the first time they were machined.

Bill S.

Kevin, thanks so much for the tip about the knock sensors. We replaced them and the car runs great. No more codes and great power from 6,000 to 7,200 rpm with no dead spots. I haven't felt that for years.

Kevin

Bill I'm glad that it worked out!

The knock sensors really do need to be changed on these 14 year old cars.

Texas993

Wow, what a great ending. What does replacing the knock sensors entail?

ScottMellor

I was under the impression that if you can actually hear pinging, you are well into detonation issues, and the knock sensors are an early warning detection and remediation system for the problem.

SA Mike

+1 inferior gas will do it