Clutch and O2 SVT Questions

[Ackmann]

New to the site, but thought the SVT Cobra guys may have more experience with the mechanicals of my car. I have an 2001 Panoz Esperante running the Cobra running gear. It's now 10 years old and has 12,500 miles. It runs out very nicely and sounds great with the magnaflow exhaust. I have a couple of questions, today I was to taking my boy to school in it and noticed the clutch felt much stiffer than when I drove it just a few days ago. Still shifts good, but feels like the resistance is all return spring. Are these clutched hydraulic assisted and would this reflect back to clutch pedal pressure?

I also see the car starting to Hunt while at idle at the lights between 850 and 1000 rpm. Do you think that I may need to change the O2 sensors even though I only have 12000 miles on it?

Thanks,

 

[Ackmann]

WMBurns was nice enough to send me this PM. I will be starting my diagnosis.

I will assume the PCM is the same as a production Cobra.

Start by cleaning the MAF. Use cleaner specifically designed to clean the MAF. The sensor is delicate and easily damaged. Don’t be too rough.

Are there ANY other drivability issues? Any Check engine lights (DTC’s)? Recent work done? Change in fuel economy?

Let’s clarify the symptom. A rolling idle is different form the “hanging” idle sometimes reported by Mustang owners. An elevated idle coasting down to a stop is a NORMAL occurrence. The PCM uses the car’s speed to activate the “dash pot” mode during deceleration. So the motor idling around 1k with the car moving is working as designed. The PCM will activate a “slow” idle once the car has come to a stop.

So let’s assume this is a true rolling idle where the idle is changing while completely stopped. Does this car have AC? (I know you are probably laughing because your car is a roadster. Please forgive me as I am not familiar with your car). If the AC were cycling on/off, this could cause the Idle to bump up to keep the motor running smooth.

OK. Let’s look for any vacuum leaks. Even the tiniest leak will cause problems. Check all hoses, lines, PCV valve, oil dip stick, oil filler cap, evaporative purge lines or any other source for outside air to enter.

A common source of rolling idle is the EGR system. For a test, remove and plug the vacuum line to the EGR solenoid. This may throw a DTC, but it is OK. If the rolling idle improves, this will let us know it is EGR related.

Next item to look at is the Idle Air Controller (IAC). Disconnect the electrical connector at the IAC. The motor should die outright or the idle slow. Post the results.

IMO, it is way too early to replace the O2 sensors. It is possible but normally there are other drivability issues as well.

Have you checked the fluid level in the clutch master cylinder? If low, this can cause problems. Does your clutch have an adjustment procedure? Recommend the FIRST thing to check the fluid level (OBTW, I haven’t the slightest idea if your car has a hydraulic or mechanical clutch).