JWT clutch/flywheel issue?
 

Hi, I'm looking for an answer and I'm hoping I can get it from here. I purchased the JWT clutch/flywheel combo, csc and master cylinder from conceptzperformance. I took my 07 Z to my mechanic for the installation.

After 2 weeks of waiting, I finally get my Z back but when I go to pick it up, the mechanic tells me it struggles to turn on. I told him my car turned on with ease before I dropped it off with him. His facial expression looked confused. He told me too that he changed the crankshaft sensor.

I took to the Vq35HR discussion page (I have a video there of the situation you can check it out if you'd like) hoping to get the answers. I was told either the flywheel was installed incorrectly or the crankshaft sensor could be damaged. I also have the service engine light in my car.

I talked to my mechanic face-to-face and told him everything I was told and the possible causes of why my car struggles to turn on when I turn the key. Let me clear this, my car turns on, it just struggles. You have to watch the video to understand. Anyways, my mechanic denies everything. He tells me the flywheel was installed correctly and that the crankshaft sensor is fine.

I went to my local auto parts store for a check engine light scanning and the code was the crankshaft sensor. I'm taking my car to him tomorrow to drop the transmission and see what is wrong.

I talked to conceptzperformance on the phone and we reviewed my order precisely and everything was correct in my part. I was asked to take pictures of the parts and e-mail them to them for confirmation.

I think it's my mechanic's fault but he doesn't want to be proven wrong. I paid $1,000+ in parts and $455 for installation.

What do you think is the problem?

****I have a video of my car on the "Vq35HR Discussion page if you want to check it out.

Thank you for your time.

AI had an issue with JWT clutch and flywheel combo I had installed 4 years ago. The culprit for me was a defective ring that the crank position sensor reads the position off of. The car would struggle to start and not start at all. What happened was that my mechanic (a JWT dealer) got JWT to do a full exchange plus an extra flywheel for me to sell to recoup some cash back from extra labour costs. How they found the defect was to put an electronic scope on the sensor and rotate the crank and saw spikes on the scope that signified defects on the sensor ring. New crank position sensors did not work obviously.

In your case since you are able to start your car I would say that the crank position sensor is failing. I would replace it first. I'm not saying the issue you are having is the same but it's another data point. I find this thing to be very precise and any little defect (we had 1) causes the car not to start at all...so I think the sensor is to blame given what I know.

Hey man
I'm not dealing with the same problem as you, however the car I purchased (2005 z) had a jwt combo installed by the previous owner and my car constantly makes a metal on metal gargling sound which goes away with the clutch in. He said it is common with all jwt flywheels.

That is common with lightened flywheels. Look up cement mixer sound. I have it too.

Yup, my SouthBend race flywheel sounds like a cement truck. No cause for alarm.

Post the link to the video here or upload it on PB or YT. I can't find it

I can say I have the jwt heavy duty clutch/flywheel combo and have never had an issue of anykind. I have a supercharger, jwt cams, etc. and a mechanic that is tops here in Northern California. As to hearing a sounds, I agree with clubhopper and trustr888, you will hear a sound (hard to describe) from the flywheel, but that is natural. I have drive on the Luguna Seca Track (Mazda Raceway), as I live 6 miles from it. I would also like to see the video, unable to locate.