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I hope for some suggestions, or maybe even a referral to someone who may know wtf is going on. Short story is made a stack of mods, twins, z32s, fc, inj, pump, cams, reg, splitfires, cooler, etc. car was tuned, started perfectly, but was very disappointing in the top end.

So i had the car re-tuned by another dude with 1000cc ID's and removed the resistor pack. Tune is awesome, good on fuel, smooth idle, very linear power delivery, and decent final figure. However the startup is now crap. Cold start is quite good, also when you turn the car off and on again within 5 minutes. The problem is when i park the car for anything between 30mins to 6hrs and try start it again. It cranks forever (30+ secs), i have to pump the accelerator, and just barely starts and struggles to get up to normal idle.

To the tuner's credit, he has spent hours on it, involving an electrical engineer and can't crack it... Injectors have been flow tested, voltage tested, pump has been tested, crank signal shows on the fc controller when cranking, plus heaps of other stuff. The tuner is a champion and has probably tuned most sydney cars on this forum, so i don't think for a second it is down to his ability, has to be some weird ass quirk...

PLEASE HELP!!!

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I hope for some suggestions, or maybe even a referral to someone who may know wtf is going on. Short story is made a stack of mods, twins, z32s, fc, inj, pump, cams, reg, splitfires, cooler, etc. car was tuned, started perfectly, but was very disappointing in the top end.

So i had the car re-tuned by another dude with 1000cc ID's and removed the resistor pack. Tune is awesome, good on fuel, smooth idle, very linear power delivery, and decent final figure. However the startup is now crap. Cold start is quite good, also when you turn the car off and on again within 5 minutes. The problem is when i park the car for anything between 30mins to 6hrs and try start it again. It cranks forever (30+ secs), i have to pump the accelerator, and just barely starts and struggles to get up to normal idle.

To the tuner's credit, he has spent hours on it, involving an electrical engineer and can't crack it... Injectors have been flow tested, voltage tested, pump has been tested, crank signal shows on the fc controller when cranking, plus heaps of other stuff. The tuner is a champion and has probably tuned most sydney cars on this forum, so i don't think for a second it is down to his ability, has to be some weird ass quirk...

PLEASE HELP!!!

If your having to hold your foot to the floor to get it started i think you might be using the flood control of the power FC which means you are getting to much fuel while cranking use your hand controller to trim this, I had this exact problem with my GTR and playing with the hand controller fixed it.

Goodluck.

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If your having to hold your foot to the floor to get it started i think you might be using the flood control of the power FC which means you are getting to much fuel while cranking use your hand controller to trim this, I had this exact problem with my GTR and playing with the hand controller fixed it.

Goodluck.

Thanks for the feedback mate. I haven't held it flat to the floor, but i have been pumping it for like 30-45sec to get it to start... I will try holding it flat and see if starts quicker, if so, than maybe it is too much fuel.

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My car is the exact opposite!

Every morning or if the car has sat for a long time, its a B**th to start. I have to turn the key one shot. If i leave it in ignition till the fuel pump runs and cuts out, i have to crank it really long and depress teh gas pedal. but once it has warmed up or even after a few hours of sitting its starts like a charm. It only does this when it sits for too long like in the mornings or in the evenings after work. Anything i can do to solve this? Fuel pressure too high?

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No smoke... U guys have nailed it, on first impressions. 4 starts so far, and every one of them a winner with foot flat to the floor!

What is odd about this is that the tuner tried leaning it right out and adding heaps more fuel, both ends of the scale with no luck. He and an electrical engineer went right over the car for like 5hrs and found nothing helped. He is prob the best known tuner on this forum too, so he is definitely no rookie...

Thanks guys, i will take this idea back to him.

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I had a similar problem with my R32 and turned out to be fuel pressure was too high, try adjusting ur fuel pressure regulator

if u have a fuel pressure gauge on it, if not take it to somone who can. On my car when the ignition is turned on

it is running 50psi. starts up after a single turn of the key everytime..

Hope that helps in some way

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What timing is it running at start?

The reason it is starting with some throttle is possibly die to the throttle allowing more air to enter the combustion chamber, which implies too much fuel while starting. Have you looked at any form of temperature correction in the maps (don't know about PFC, but Wolf has a seperate temp compensation map).

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  • 2 months later...

Hey guys, digging out an old thread, i forgot to check back on this...

It is running BP98 now, no E85 as yet.

I don't believe the PFC has a temp compensation map, but i could be wrong...

Trent, i will forward through my map as soon as i can download it.

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