odd running issues

[mynheers_a_pint]

Hi all,

I bseem to have a bit of an irritating fault at the moment and I'm not sure how to remedy it.

When driving from cold, the car hesitates between 2-3.5k RPM. It is very jerky at partial throttle, but clears at 4k rpm with no issues. When warm it seems clear but the cloud of fuel smoke on boost is quite large and occasionally, yesterday for instance, it will throw out intermittent clouds of black smoke at high RPM. When i say intermittent, i meran it throws a cloud, clears, then thros another and clears, all in very quick succession.

Coupled with this, my battery warning light seems to be on consistently, though my alternator is new, and my battery is fine, or so it seems. I have re-grounded my Z32, the TPS has been set. Fault codes are a sticking point as it was throwing up a F11 but now I'm only getting an F55.

Other points; when it was mapped, my Lambda sensor was kaput, but I have since replaced this. It made no idfference when i changed it in the beginning, so i doubt it is this. I also have a blow at the downpipe, but again, I can't see how this would effect it. Plugs are new (the BCR8ES ones everyone recommends), the dissy. coil and rotor are new and I have magnecor leads which are also fairly new...

Vacuum leaks are the only thought i have, but i weouldn't know if this would cause an issue like this and i'd of expected other issues, such as a high idle. Any help is apprecaited.

 

[Smo]

Have you cleaned the MAF recently bud? I had a similar issue years back, turned out to be a small fibre on the sensor which was wiggling with the air current causing the car to intermittently overfuel - once cleaned up it ran perfectly.

 

[Animaldaz]

Have a really close look at the wiring at the alternator, they break there.

 

[mynheers_a_pint]

Have you cleaned the MAF recently bud? I had a similar issue years back, turned out to be a small fibre on the sensor which was wiggling with the air current causing the car to intermittently overfuel - once cleaned up it ran perfectly.

not recently, no. I'll have a butchers this weekend as I'd intended to check the wiring on the MAF anyway.

I had noticed a single wire hanging down by the alternator but i have no idea what it is- very small gauge, a single spade connector on the end, in a sqaure plastic sleave. As far as i can see, all the earther are attached properly and are fresh, since the rebuild (1 year).

 

[Animaldaz]

That'll be the wire that puts the light out on the dash then!

 

[Animaldaz]

It goes on the back of the alternator

 

[jambo_gtir]

Or it's the one that goes to the air-con pump? Since i removed my pump i now have a spade connector left over that is part of the same loom as the alternator one.

 

[pulsarboby]

yes thats the ac pump wire
the earth to the alternator is on a ring connector generally held in by an 8mm bolt

 

[mynheers_a_pint]

Or it's the one that goes to the air-con pump? Since i removed my pump i now have a spade connector left over that is part of the same loom as the alternator one.

That sound abour right, now you mention it.

Am i correct in assuming that the fuel system wont be the issue here (stuck injector, dodgy fuel pump (walbro)etc)? And the same with the vacuum system- am i correct that this would be causing other issue if there was a buggered hose? And finally, however doubtful it seems to me, could the issue be caused by a duff battery?

I want to attack all the logical things tomorrow before i go to the garage so if i can tick the above off the possibilities list, or at least a few of them, that would be great.

Thanks in advance.