Thateguhate

Hey guys, So recently I had replaced my clutch/flywheel due to the other one going out at the track. I've put about 400 miles on it and it's felt great so far. My wife has a G35 with the same combo so I already knew what I wanted when it needed to be replaced. My concern is that I cannot distinguish whether the clutch is what I'm feeling or my TPS is going. Randomly when driving, Mostly in 1st and 2nd gear I feel a jumpy sensation. This happens sometimes while I'm already in gear coasting with my foot off the clutch and my other firmly on the gas and even sometimes when I'm at 3-4k without touching either pedal really. I have also felt a minor spudder when I gas it up to about 7 or 8k under full throttle.

I know my map sensor has been going so I just ordered an OEM map to replace the one I have but based on the feedback I get from the car just in case that is actually it. Can you guys tell me based on your experiences what I might be dealing with? I don't intend on replacing the throttle body so if it comes down to it I'll probably just get an Omnipower replacement TPS if needed but I don't wanna waste the money if it could just be the flywheel. I don't feel this in our other car so I'm unsure if it's just an s thing.

Matts2k87

I have a 7.5lb flywheel and no problems besides wanting to stall out from a stop start if you don't give it a little more gas then I used to. Nothing like you're experiencing

jkelley

I can't really comment on which or what it may be but I used a Bluetooth OBD2 scanner that linked to my phone which ruled out a TPS issue for me. I could see the live TPS position as I drove. You would be able to see if it does indeed jump or fall during the times you are talking about.

I think it was like $25 shipped. I use it all the time. Tons of useful data from our ECUs.

Thateguhate

I have a 10.5 lbs Chromoly and it's been great until recently. No chatter or anything. Thanks for the input, I've driven with lightweight flywheels for a number of years now and have yet to experience this until now.

Good idea actually. I need to buy an obd 2 scanner, I borrowed my buddies but it doesn't have the live data on it. I actually did put my map sensor in today and the car does feel much more consistent and a bit more responsive. I'll have to keep driving it to be sure as I just reset the ecu but if all else fails I might as well invest in getting something that will show me live data so I don't waste money on buying parts I don't need.

shind3

What's the sampling speed?

jkelley

I'm actually not sure. For my alternator for instance the sampling speed is much higher like once every second, but for coolant temp it only gives me lumps of temperature - unlike a true analog signal. For instance the temperatures I see are 178.6, 179.2, 180.6, 181.4 or something like that but if the temp is in that range it's going to pick one of those values. And I think it samples every 4-5 seconds.

When I tested my TPS the sample had to be at least ~0.1 seconds because as I was opening/closing the throttle the signal followed up and down very very quickly.

shind3

When I tested my TPS the sample had to be at least ~0.1 seconds because as I was opening/closing the throttle the signal followed up and down very very quickly.
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Cool, good to know.

What phone app did you use? Torque?