Odd revs

mdw · July 10, 2019, 13:12

Ive done about 2k miles since buying this roadster, all good. Today doing 2k rpm in 4th I put my foot down to accelerate. Revs rise to 3k then drop to 2.5k over about 2 seconds and rise again past 3 as they should. NO jerk or judder and it did this a couple of times and then not at all over the next 40 miles. No codes showing on and obd reader using torq app. Any ideas?

StuC · July 10, 2019, 13:23

Any problems with static revving? I am wondering about the throttle cable movement.

Clean maf?

mdw · July 10, 2019, 13:36

Static revs are fine smooth and where they should be. Maf cleaned about 200 miles ago and all good since.

StuC · July 10, 2019, 14:14

did you floor it to accelerate or was it a more gentle thing?

mdw · July 10, 2019, 15:18

floored it

StuC · July 10, 2019, 15:23

It's a weird one for sure.
Maybe just see if it happens again by trying to repeat the circumstances.

Carolyn · July 11, 2019, 08:50

Sounds like a spot of clutch slip to me.

jonbill · July 11, 2019, 09:12

Did the revs dip or did the tacho reporting of revs dip? Or both?

McMr2 · July 11, 2019, 12:36

Quote from: Carolyn on July 11, 2019, 08:50Sounds like a spot of clutch slip to me.

I had the same thought. Almost identical symptoms to when I test drove mine, particularly in the higher gears. It had done 65k or so and it was a new clutch in my case. However, worth ruling out other causes before forking out.

mdw · July 11, 2019, 17:02

Quote from: Carolyn on July 11, 2019, 08:50Sounds like a spot of clutch slip to me.

That was my initial thought as its 90ish k miles with no sign of replacement in the comprehensive list of bills. However unless there is a different way of testing an mr2 clutch it seemed ok on testing. It also made the journey all the way home 40 miles with no further signs.

It was the revs showing a dip. Cant remember if engine note changed.

Ardent · July 11, 2019, 17:41

As every day is a school day.

I thought if a slippy clutch is in question, Revs spike rather than dip.

Re-reading the OP.
did you actually accelerate or speed remained the same?

mdw · July 11, 2019, 21:22

Probabay speed stayed the same however was concentrating on the revs and the road as was in the m20 smart motorway road works zone.

Ardent · July 11, 2019, 22:31

quote "and then not at all over the next 40 miles."

Perhaps the best course of action right now is to just monitor. Drive as you would.
Try to re-create.

McMr2 · July 11, 2019, 23:54

Quote from: Ardent on July 11, 2019, 17:41As every day is a school day.

I thought if a slippy clutch is in question, Revs spike rather than dip.

Re-reading the OP.
did you actually accelerate or speed remained the same?

Quite correct - I've misread the OP, I thought the description meant the revs rose past 3k without a change in road speed.