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Hey everybody!

Hoping some ppl can throw me a few pointers.

My car has been off the road for quite some time on account of me loosing my licence, so while it's wasn't going anywhere I thought i might as well do some well deserved modifications. Now I'm done and the car has trouble starting, it won't idle, it runs really rough, but if i squeeze the gas, she'll rev, but it almost sounds like she's running minus a cylender, then when I take my foot off the gas, blah, it dies.

I've gone through some of the basics today, but I can't find out why it's running so rough. Can someone shoot me some pointers?

This is the list of work I have done to the car while it was in my garage:

- Stainless steel extractors

- top mount turbo

- external wastegate

- dump pipe

- electronic boost controller

- FMIC

- BOV

- Apexi PFC (crushed the original ecu, can't even test it on stock ecu!)

- Z32 AFM

So that has taken me about 5 months on weekends and so on, now I've got to troubleshoot the fault.

Any thing I may have installed or done improperly that could cause this?

If I can't figure it out, I'll get a mechanic to look at it, but I figured I got this far on my own, I'd love to fix it on my own. (with SAU members help of coarse!)

I have included a pic of the engine bay if it helps.

- post-20285-1222940127_thumb.jpg

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https://www.sau.com.au/forums/topic/238637-rough-start-no-idle/
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when was the last time you put decent fuel in it? have you setup the power fc to use the Z32?

i can also see a breather line that isn't plumbed in anywhere.

also where does the IAC valve get its main air feed from? it looks like you have it going to the silicon elbow.

Edited by QWK32
when was the last time you put decent fuel in it? have you setup the power fc to use the Z32?

i can also see a breather line that isn't plumbed in anywhere.

also where does the IAC valve get its main air feed from? it looks like you have it going to the silicon elbow.

I put in 20 litres of Mobil 8000 on Monday.

The Power FC is set to use the VG30 (Z32) AFM.

The breather hose would normally get plumbed back into the intake, but it's not needed, I'll slap on a mini filter later.

And the AAC does get it's main feed from the silicon elbow. It too is plumbed into the intake on the stock setup.

sounds like BOV leak, can you remove the BOV and block the port where it would normally go? if so try it and you might find thats your problem..

All these parts are brand new, besides, the motor revs ok at high rpm when the drop in pressure would be at it's highest. I don't think it's a leak anywhere. I've heard this car run with a leak. Like I said the idle is pretty rough.

have you checked for vacuum leaks, and that you have spark out of each coil? if its a dead coil you'd be seeing fuel smoke because its missing and not igniting all the fuel.

if you have and they were ok, is it running rich because of the tune on the power fc. if its your tune that is too rich than you will be fouling the plugs causing it to run like crap.

how have you got the IAC line tapped into the silicon elbow? just curious on how its sealed and clamped.

maybee the tune is out, or the maf might be faulty both of them can cause a rought idle,

timing can cause huge issues aswell

The tune is set to default, as the PFC comes out the box, with the exception of the boost control setting disabled and the Z32 MAF sensor option enabled.

The MAF sensor is fine. Both the hand controller and my multimeter confirmed this. The unit came off a working car.

Timing? Possibly, but I didn't go anywhere near the timing. And to go out by that much???

have you checked for vacuum leaks, and that you have spark out of each coil? if its a dead coil you'd be seeing fuel smoke because its missing and not igniting all the fuel.

if you have and they were ok, is it running rich because of the tune on the power fc. if its your tune that is too rich than you will be fouling the plugs causing it to run like crap.

how have you got the IAC line tapped into the silicon elbow? just curious on how its sealed and clamped.

I've checked and double checked all the vacuum hoses.

I haven't checked the plugs yet for a few reasons:

- I just popped in 6x new NGK Iridiums

- I just cleaned and resealed the coil packs (Misfire under load was an issue)

- and last i checked, the computer should be able to keep the motor running even if it was one cylender down.

From what I can tell, the computer is either not getting what it should to kep the motor running, or there is a piece of hardware not doing what it shoud be to keep the motor running.

QWK32, I tapped into and resealed the silicon elbow using a little trick I learned from working with large dia pnumatic hoses. It was ahellavalot easier than welding a tap onto the aluminium pipe.

Well

1. Without a tune... your really not giving yourself a chance.

2. Im also with above - AFM might be too close. They need a bit of room or they get unhappy too close to the compressor

Get both those fixed and it should be right, Z32 with a base map... to hard to tell without tuning :(

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