Need Help!

My car suddenly jerk (kind of suddenly loss of fuel or air) at every 7500 rpm. Only @ 7500rpm.

it jerks and than suddenly continue to rev up......

 

Could be a bad fuel pump. Search it up. From what I have read its a e-z fix
I would check my plugs. They could be bad not getting a good charge at the high RPM's.

 

Will check it. But just thinking it is wierd because it only happen @7500rpm.

Could it be the injector which start @ 7500rpm

 

check your Aux port.

 

Don't think it is an oil issue. I'm using Greddy (5W40) since day 1.

 

how many miles on the car

 

6 speed MT JDM. now about 45k miles.

 

Are you sure you are not hitting the rev limiter?

 

RPM redline @ 9000. have been remapped by RE Amemiya.
no problem for years until lately....

 

pull the room fuse?

 

sorry, but what is the room fuse?

 

Footwell fusebox, marked 'room' controls constant power to the ECU.

.....but it sounds like a sticky actuator on the inlet manifold, to me.

S

 

Do this: https://www.rx8club.com/series-i-do-yourself-forum-73/diy-mazda-zoom-power-engine-cleaner-engine-cleaning-seaform-142852/

That should fix your problem.

 

Same thought here.... Although I thought those come on earlier (6800), but it's possible you're not feeling it till a half-second later or something.

You can take that apart pretty easily and make sure the valves are opening smoothly.

 

Done the above with the Liquid molly and compression check o.k.

Didn't help to resolve the 7500rpm jerk!!

 

Dear ALL,

I'm still having the problem. When I rev my rpm, it still hesitated @7500rpm (as though insufficient fuel for a 2 seconds) and then continue to climbing to 8500rpm and feeling lost of power.

It doesn't seem to be a mechanical problem. Do you think my ECU is the problem?

Anyone has experience this problem on 6MT JDM spec.

Need help urgently.

Thanks