Urgent Help Needed

[R31Nismoid]

When you say replaced...

How?

With known working ones?

2nd hand ones? (that are unknown?)

etc

[ECR 033]

When you say replaced...

How?

With known working ones?

2nd hand ones? (that are unknown?)

etc

Igniter pack - known working one

Coilpacks - known working ones

Plugs new

Fuel regulator - known working one

Injectors - new

Z32 AFM's - Used (unknown condition)

Replaced all hose clamps - New

checked all possible air leaks.

new power fc (used)

new o2 sensors (new)

New temp sensors (new)

New ignition wiring harness. (new)

cas - known working one

[RB ONEVIA]

sounds like my RB20, yours is more severe...

[SLYDA]

Hmm i had this issue, went through everything coils, plugs, vac leaks.. it ended up being carbon buildup inside the head which was causing the valves not to seat correctally. Had it run a a Carbon Clean machine and my tuners workshop and it fixed the issue. now got a nice idle and no miss. By the way i believe this to have been caused by me running the PowerFC Basemap for so long and it running rich as. Ive got no idea where you could find someone with one of these.. there aparantally rare as!

Ive included a pic its the funny red thing connected into my fuel system:

[ECR 033]

Hmm i had this issue, went through everything coils, plugs, vac leaks.. it ended up being carbon buildup inside the head which was causing the valves not to seat correctally. Had it run a a Carbon Clean machine and my tuners workshop and it fixed the issue. now got a nice idle and no miss. By the way i believe this to have been caused by me running the PowerFC Basemap for so long and it running rich as. Ive got no idea where you could find someone with one of these.. there aparantally rare as!

Ive included a pic its the funny red thing connected into my fuel system:

Thanks for the reply

My head was completely overhauled cleaned and with all new gear fitted (bar stock cams).

cheers.

[ECR 033]

Would a dodgy TPS cause any issue like this?

[Strik3r]

AAC valve might cause the idling problems, but not the misfire under load.. still worth cleaning it out though.

what heat range / gap are you running on your plugs ?

[ECR 033]

oh forgot to mention cleaned the aac valve already...

plugs are BCP7ES Gapped to .8

[ECR 033]

maybe it is still the afm's as i don't know if the new ones are 100%

(when i drove it) - it seems to clear up at various rev ranges but when throttle is backed off it dies and splutters, and missfires at idle as per usual

[tacker]

is the plumb back bOV working i had an issue with the turbos creating shuffle even at an idle the air was being read by the AFM 3 times which was sending the idle all over the place. If its not then your excess air is more than likely heading back out your AFMs

we also had an issue with a valve shim that was incorrectly ground to suit cam, seems it was not perfectly flat and after the valves settled in it would be unseated some of the time causing a miss, not sure this is your problem but if you have had head work then worth checking.

[ECR 033]

is the plumb back bOV working i had an issue with the turbos creating shuffle even at an idle the air was being read by the AFM 3 times which was sending the idle all over the place. If its not then your excess air is more than likely heading back out your AFMs

we also had an issue with a valve shim that was incorrectly ground to suit cam, seems it was not perfectly flat and after the valves settled in it would be unseated some of the time causing a miss, not sure this is your problem but if you have had head work then worth checking.

i have been concerned about the stock plump back bov's being dodgy... mainly cause i have run out of ideas..

how can i check to see if this is the problem? pull them out and block the pipes?

[Rowdyr32]

Is it a missfire or no fire or rough running. This needs to be sorted first.

If it begins to misfire ro run rough disconnect each coil pack individually while engine is still running until you find the cylinder as the rough idle won't get any worse. Next pull the coil pack out with it connected and see if it is sparking. Try not to get yourself. Does it missfire out of the inlet or exhaust side at idle if you turn the cas. Is one spark plug wet or darker than the others?

Have you done another comp test on it since engine rebuild. Do one cold. Then one hot. This will tell if it is a mechanical issue. As mentioned it could be valves or I had a gtr with a cracked ring landthat only ran rough after 5 minutes. Gets worse as it heats up.

With the pfc if you still have it go to the part that shows all the sensor voltages. Not the normal display. You might be able to see if the afm's are playing up as the voltages will have a big split or one will just drop out. One of the other sensors maybe jumping around so look at them all.

Hope you get an answer soon. I hate electrical issues.

[ECR 033]

i did a compression test and got the same reading across all 6

also fitted a new fuel pump

and hooked up the compressor to the intake and founds some small leaks.... fixed them up, still no different.

still misfires at idle (not a complete cylinder drop) just a slight one...and if i give it a rev and let my foot off... the revs die to about 500rpm and it sounds like its running on 5cyl.. and puffs a cloud of unburnt fuel out the back. then the revs pick up to 1100rpm and missfires as normal.

[ECR 033]

oh and the afm voltages seems ok... no sudden drop outs etc.

[Rowdyr32]

You said the motor was out. Have you setup the throttle position sensor correctly when it was re installed. Even if it wasn't removed you should check it. There are two things you need to set. Read the manual if you haven't done it. It tells the ecu when the butterflies open on one circuit and also what % the throttle is open on another.

Just another idea

[ECR 033]

You said the motor was out. Have you setup the throttle position sensor correctly when it was re installed. Even if it wasn't removed you should check it. There are two things you need to set. Read the manual if you haven't done it. It tells the ecu when the butterflies open on one circuit and also what % the throttle is open on another.

Just another idea

ill read up on that... cheers.

also just found a small leak in the hard plastic pipe that runs from the bov's to the intake.... not sure if this would cause my issue?

[ECR 033]

just checked the power fc

and i have a little black dot next to these sensors:

[O2H] Oxygen sensor setter

[F/P] fuel pump

[iGN] ignition

[WRN] Engine warning

does this help anyone solve my issue? cheers.

[nemo]

is the plumb back bOV working i had an issue with the turbos creating shuffle even at an idle the air was being read by the AFM 3 times which was sending the idle all over the place. If its not then your excess air is more than likely heading back out your AFMs

we also had an issue with a valve shim that was incorrectly ground to suit cam, seems it was not perfectly flat and after the valves settled in it would be unseated some of the time causing a miss, not sure this is your problem but if you have had head work then worth checking.

How did u get rid of your turbo shufle dude? i got the same problem on my gtr.

[nemo]

Sounds like a blown turbo!!!!! Im affraid to say.

[ECR 033]

Sounds like a blown turbo!!!!! Im affraid to say.

ummmm....

brand new to4z... hasn't even come on boost (cause i can't) as the engine is new.

ok so i worked out how to adjust my injectors down ... i put them down to 65% (700cc) it seems to rev alot better and doesn't try and stall (as much) or blow as much black smoke.

still have the missfire.... but... when i adjust the Injector corection from 1.000 to 1.300 the misfire seems to go away. (the car still trys to stall at times if i rev it and let my foot off).

does this shed any light?