reintel

Problem solved! Its was the boost sensor giving the problem. Replace and retune had solve it completely.

Rephrase back 'It doesn't sound like its having misfire'.

It does sound like its having misfire. It just that the engine feels like cut off momentarily. I had replaced my coilpack to superspark.

Yes. but in my previous set up I have no issue with it and works perfectly. I did replace it with the OEM unit and still the problem persist.

Hi guys, Need some advise and opinion. my ER34 GTT manual just had completed top overhaul repair work, replaced metal head gasket and engine started well. However, as we trying to get further check for AFR and other tuning issue, car jus like had speed cut whenever past 4,000 rpm. When back to the workshop and hook up the diagnostic tools. Found out the speed cut sensor problem. I had fix with HKS SLD and for 2nd round, I remove it and hook it u directly to OEM condition but problem still persist. My question is, if the speed sensor giving wrong signal or faulty, wouldn't it affect my meter reading? So far all meter work like normal. 2nd question. There are times I manage to past beyond 4k if running under boost and hitting higher speed. shoudl it cut me off if the speed sensor faulty. 3rd question. Can it be other problem. Boost cut? fuel cut? I know if for boost cut, I would have rich retard feeling but this just feels like engine cut off whenever it hits higher rpm/speed when boost is climbing. Need a great help here. thanks!