Has the hoses been checked for leaks? Also try the fuel pump / fuel filter as well.

 

Please help

A friend has a Lotus Elan which keeps cutting the revs under acceleration. The knock sensor has been changed but has not made a difference. Some time ago the ECU was remapped and it is running slightly higher boost pressure, but this problem developed almost a year after the work was carried out. He has tried millers, but to no avail. I know this isnt an Impreza, but hopefully the cure for detonation may be the same

Thanks

 

Are you sure its det, and not iffy spark plugs...?

Ron

 

Thanks

But the plugs have already been changed. Any other suggestions?

 

Thanks Jay

I will get him to inspect all associated hoses for leaks. How do you check the fuel pump? Or is it a case of change it for a new one?

Thanks again

 

Get a fuel pressure gauge. As well as pump it could be regulator or a starvation problem. That's if it's fuel and not electrical.

 

For what it's worth I think you may be off target with det'. Agree sounds more like electrical or fuel supply. I had similar misfire (old Jag) and a decent set of plug leads cured misfire. If you can remove fuel line from pump then see if it churns out fuel when ignition turned. Also obvious but often missed things like blocked fuel filter. Let us know.... DL

 

thanks for the replies

Just to clarify some of the details. The engine violently hesistates and the revs drop approx 1-2000revs. This happens during normal (not hard) acceleration, between 2-3000 revs (so not on boost/just coming on boost), particularly when the engine is cold.

Any other help appreciated