kick in the chest!

[amccan10]

Can anyone help me diagnose a fault with my classic please.

Driving along in 4th gear plant the accelerator and the turbo boosts up and pulls very strongly but as the higher rpms are reached it seems as if I literally hit a wall. Very noticeable kick back.

The car is mapped to 335 bhp on a converted front entry TD05. Within the last week or so I've had a center silencer added and the turbo actuator adjusted as it was slightly out and making a constant ticking.

It has only started within the last few days but it is very unnerving.

A few others have suggested that the MAF or walbro fuel pump could be failing however they're both under 9 months old.

Any advice would be greatly appreciated.

Andy

[NITO]

Fuel Cut. Too much boost. IIRC the fuel cut is set to 1.3bar on these, you can either map it out or there is another way around it but not recommended unless you have a boost gauge and you know what you're doing.

ps. If mapped it may be the boost cut level was raised or not, all depends on how it was setup. Above figure is on standard cars. There is a vacuum hose that feeds the fuel cut boost sensor located on the drivers side just under the front suspension turret. It has a white round filter with furry felt around it. Pulling this off disables the fuel cut as it can't read boost but you'll lose the protection that comes with it and your car may not be mapped for the higher levels of boost you're experiencing.

Edited by NITO on Friday 1st March 14:21

[amccan10]

So this could have been caused by adjusting the actuator and not letting it release excess boost?

[johnnyr6]

That's my first thought. The only prob i have is if your car is mapped the mapper would have moved the fuel cut higher. Is it the standard ecu?

Defo sounds like you've adjusted the actuator too much. What boost you getting?

If you have a boost gauge readjust the boost to about 1.1bar and see how it is.

Johnny

[SCEL1SE]

I had this on my Evo 6, as you describe, like hitting a brick wall.
It started after I put a new exhaust, downpipe back.

[amccan10]

No idea what the boost is.
Don't think it's a problem with the map, been fine until the last week when the centre section was changed and actuator adjusted.

Hmmmm

[NITO]

Adjusting the actuator changes the boost setting. You are running too much boost which is bringing on the safety cut which is there to protect from damaging your engine by overboosting. You should never adjust an actuator without at the very minimum a boost gauge, this is exactly how people blow their engines up! As standard boost cut is at 1.3bar.

If yours has been mapped, it may be that the level was raised to 1.4 or 1.5bar or 1.7 bar who knows?? so you are at risk of damaging your engine if you don't ascertain what boost you're running. You should get yourself a boost gauge or a boost controller, if you go adjusting boost blind you're asking for trouble and you're lucky you have the boost cut still and it wasn't mapped out totally.

Good luck
Nito

[amccan10]

I didn't adjust it myself, it was in at the garage but sounds as if its not been set right.

Thanks for the help guys

[NITO]

Good luck with getting it sorted, sounds like it just needs winding back a touch.

Regards
Nito