First off, Just a quick hello to all as this is my first proper thread.

 

Anyways, I have a J-spec TT manual '94, lovely car & shedloads faster than my old Pulsar GTi-R until this morning :( :headvswal :headvswal

 

Heres the problem, the car runs absolutely fine up to 2500rpm, then feels rough as a badger arse, boost pressure looks fine at idle no warning lights on.

Only thing I have noticed is that fuel pump is buzzing almost constantly, had same noise on Pulsar pump prior to it dying.The Zed is standard aside a Blitz SUS.

Thanking you all in advance,

Chris.

First of all welcome bud,

I would start by checking all your fuel line connections, then check you coil pack connections, when was the last time it had a good service ?? how long was it standing before you bought it as the fuel might be bad.

Next thing would be to take it too some one who has got a Conzult and get it checked for faults in the ECU and the O2 sensors.

Good luck fella hope this helps :cool:

Matt

Thanks for your thoughts Matt, had new oil & fuel filter 3 months ago. I've had her since October on & off (had re-con gearbox & diff from Bonsai cars under warranty) also was running rough throughout rev range in December but that was due to cambelt slip which was sorted. Could it be fuel starvation??

A dodgy AFM will cause this type of problem, try an ecu check and see what codes come up.

 

HTH

Thanks for your thoughts Matt, had new oil & fuel filter 3 months ago. I've had her since October on & off (had re-con gearbox & diff from Bonsai cars under warranty) also was running rough throughout rev range in December but that was due to cambelt slip which was sorted. Could it be fuel starvation??

 

Sounds like Air Flow Meter - runs in 'get you home' mode if there's a problem... disconnect battery, unplug AFM, clean connectors, reconnect, connect battery after (1/2 hour ithink!? to reset ECU - never been an issue for me cos I always end up leaving it disconnected for hours while I fix little bits I find!!) and it should be ok - although ECU will take a couple of hundred miles to 'relearn'.

 

HTH

 

Rich

Chris, if you check out 300Zx.org.uk then there is a plethora of faults associated with rough running/stumbling/idling. It took me 3 months and £800 before i found out my problem (similar to yours). My problem was that the HKS filter had disintegrated and got sucked over the AFM (air flow meter). This was buggering up the mass reading. I got a new filter, cleaned up the AFM and now it only stumbles when cold very occaionally. The problem manifested itself by not wanting to rev over about 2500rpm. So it could be your AFM playing up. There is a method of testing it in the rough running/stumbling/idling 'How To' involving a multimeter, give it a try.

 

Mark

AFM, for deffo!!

A dodgy AFM will cause this type of problem, try an ecu check and see what codes come up.

 

HTH

 

where abouts in Chester are you bud?! You must be the guy who keeps causing me to get *****cked by the missus for driving without insurance (mine's off the road at the min...!)

 

Rich

Thanks for the help guys, it just so happens that I have a spare AFM at home so I will give it try!!

Chris.

where abouts in Chester are you bud?! You must be the guy who keeps causing me to get *****cked by the missus for driving without insurance (mine's off the road at the min...!)

 

Rich

 

I'm in Upton mate. It can't be me whose getting you b******ed, I've walked further than this cars been driven since I've had it :D