The symptoms

 

Only does it when engine is up to temp

Appears to be near side bank as the exhaust that side spits and shakes lumpy when up to temp

Very light throttle then clears up as the revs rise slightly

The lighter the throttle the more violent the mis/hesitation

 

So far;

 

Changed the spark plugs

Swapped the coil packs side to side

Checked the injectors have resistance all the same as each other

Checked and cleaned all plugs inc lambda, water temp, throttle position injector and coil pack

 

What now?

By the way, I replaced my ngk r pfr6b 11c to denso k20tt

 

I am now thinking I have been sold the wrong plugs?

them plugs are wrong to start with mate

Tw things to check

 

MAF and Faulty CAS ?

I am swapping them plugs tonight, what's the procedure for checking the cas? I unplugged the maf and it ran terrible, 100% worse-so plugged it straight back in..

Have you done a boost leak test?

one of the simple things to do on a Z is to clean every connector you can get to in the engine bay, can make a differnce ;)

By the way, I replaced my ngk r pfr6b 11c to denso k20tt

 

I am now thinking I have been sold the wrong plugs?

 

ngk bkr7eix never failed me yet on any car i can think of including my own z

The symptoms

 

Only does it when engine is up to temp

Appears to be near side bank as the exhaust that side spits and shakes lumpy when up to temp

Very light throttle then clears up as the revs rise slightly

The lighter the throttle the more violent the mis/hesitation

 

 

 

So far;

 

Changed the spark plugs

Swapped the coil packs side to side

Checked the injectors have resistance all the same as each other

Checked and cleaned all plugs inc lambda, water temp, throttle position injector and coil pack

 

What now?

you may have coil pack wiring that's breaking down due to age and heat

it may be that despite showing continuity that its breaking down and building up resistance in the wire and not giving enough juice to the coils

is it worse when its warm ?

I think you need to get the right plugs and make sure they're gapped correctly.

Check the timing with a timing light - it should be at 15° unless its been mapped to run on something else.

Do a boost leak test

Get it on conzult to check all the settings etc. things like the TPS being out is a fairly normal thing

without hearing it or knowing how bad it is its pretty difficult, but here's a few things to try:

 

clean both TBs,

 

if you have a BOV to atmosphere, check it isnt jammed open.

 

adjust both throttle bodies to ensure they are sync'd

 

check all vac hoses and manifold leaks (easiest way is to inspect all hoses and do a boost leak check)

 

check the EGR isnt jammed open.

 

check each plug with a strobe light so you can identify if its spark drop-out and on which cylinder - might be a dodgy fet on the PTU.

 

do a power drop check with a consult - or pull each coil pack plug to identify the worst cylinder.

 

check all live values on the consult to make sure all sensors are reading sensible values and there are no hidden faults.

Also, could be the put breaking down, especially if its a series 1

Also, could be the put breaking down, especially if its a series 1

 

? Me no understand..lol

Sorry, predictive text. i meant the PTU

Sorry, predictive text. i meant the PTU

 

aah, that makes more sense..lol

Also, could be the put breaking down, especially if its a series 1

a put put :)

a put put :)

 

lol. put put BANG. Is the norm I think. :)

lol. put put BANG. Is the norm I think. :)

 

 

lmao so true :)

Tested the ptu, got 14v out of each, set the tps to .45. It's still spitting the near side exhaust. And still hesitant on light throttle ...

Maybe worth checking the connectors to the vvt, sounds like you may have a dodgy connection.

Try disconnecting the left hand bank to see if it makes any difference.

Tested the ptu, got 14v out of each,....

 

inconclusive,

you would need to watch it with a scope to see if its triggering each coil.

Swapped over the O2 sensor on the near side, and so far so good..

Hey mate,

How are you getting on with this issue? Sounds bit like mine... Has swapping the O2 fixed it?