Hi guys,

 

finally got me Zed back from the garage but it wont go above 7psi??? Jeff TT tells me it is most likely in safety boost as he chipped it for me and put boost jets on etc etc.

 

Can anyone help at all cus my car feels really slow, well standard boost anyway (BORING)......:rolleyes:

ok will do.

 

probably worth taking out sparkies then and wire brushing them while I'm at it.

 

what is the gap supposed to be ? and I'll check that while I'm at it.

 

 

Still, why would it run ok at higher revs, and why would the throttle responce be so monged if it was the spark plugs ?

 

stu

thanks for the help all.

 

I traced the idle/throttle problems to the vaccum pipe coming off the driver's side of the plenum (to brakes ?). They had split it taking it off. For now, I've botched a seal on it with insulating tape and voila ! no more idle problems or throttle hesitation.

 

however, all not quite all well.

 

I think I can still hear air coming out from passenger side at the rear of engine somewhere.

 

In particular if you drive at 40mph or so in 4th and put the thottle on a bit (not so much as boost to go +ve) there is a horrible sucking air rattley noise coming from there or there abouts.

 

Also, if you blip the throttle from tick over, you still get a wee cloud of black smoke which ain't good.

 

I'm going to demonstrate this to the workshop tomorrow, but anyone got any further ideas what it could be ? the black smoke sounds like some excess air still getting in and the engine over compenating with fuel (?), but the weird noise is a worry.

 

I've cleaned all the plugs, connected for the tps, etc. and as I say it's definately running well now when you are driving it apart from the weird noise and the black smoke :-(

 

I've disconnected the battery again tonight to let the ecu reset in case it had compenated for the air getting in before, just in case that was it, but I doubt if that's it.

 

 

stu

Have you checked the PCV valves + hoses ?

The rattling sound you hear could be the PCV valve.

 

The PCV's and hoses are at the back of the engine and under the plenum and are a bit hard to get to if they need to be replaced.

 

Also the hose in the middle of the balance tube running to the idle control valve has the tendency to dry out and split.

 

-Eric

thanks. will check out.

 

according to the diagram at courtesty the PCV valves looks like they are on the sides of the engine ?

 

stu

yup, on the sides at the back of the engine

Originally posted by lymon

Have you checked the PCV valves + hoses ?

The rattling sound you hear could be the PCV valve.

 

The PCV's and hoses are at the back of the engine and under the plenum and are a bit hard to get to if they need to be replaced.

 

Also the hose in the middle of the balance tube running to the idle control valve has the tendency to dry out and split.

 

-Eric

Coincidentally there's a Group Buy on these going on at the moment...

 

http://www.300zx.co.uk/forums/showthread.php?s=&threadid=18394

 

You'll have to be quick though! :D

think they are ok

 

the workshop thinks the noise is the exhuast blowing a bit. probably not sealed properly when refitted after replacing gearbox.

 

could this in itself cause the engine to run rich ?

 

it's went totally buggered again at the moment, and the ecu is showing the temp sensor open (code 13), so something is still loose there, but even when this was ok it was running rich.

 

so I'll sort the temp sensor out ok which should just leave the rich running.

 

what do you think, could it be the exhaust ?

 

stu

a tempsensor that gives incorrect readings to the ECU can cause the car to run (very) rich.

 

if the exhaust leak is before an O2-sensor it could cause the car to run rich as well, but only on one cylinderbank..

 

-Eric