Spluttering and heisitation in forth gear
Turbo Mini Forums

Hi,

I've just had my 998 set up on the rolling road where it made 102bhp and 89ftlb, it was set up in 3rd gear as they guys said it wouldn't pull in 4th on the rollers, 2.9fd

The car drives really well up until you get into 4th gear, I can hit the rev limiter in 3rd at 90mph change into 4th and it just splutters and I lose all power and has compressor surge, readings on the afr go very lean,

I can take it up slowly in 4th gear I can cruise at 70 fine, as I get to about 80mph on boost it will splutter I have to let off the throttle and put it down again and it will be ok,

Not really sure what the problem is and I don't really want to take it back to the rolling road if it's just changing the carb spring or something easy 👍🏼

Edited by coopdog on 4th Jul, 2018.

I think I’d start with monitoring what fuel pressure is doing on top gear.

Also take a look at the balance pipe a pin prick hole can cause these exact symptoms. Been there felt like a total fool when I found the issue.

Edited by Mr Joshua on 4th Jul, 2018.

Own the day