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Hey guys,

I've been looking at thread trying to find the answer to my problem but I'm still confused and don't know where to start.

OK so I'm running a GT35R, 850cc injectors, Z32 AFM, walbro fuel pump, power fc (not running the O2 sensor because it made it rich as) etc etc.

I got it back from the tuners 2 weeks ago and he said he couldn't take it over 14psi because it was begnning to sputter at high RPM anywhere above 14psi, so he just placed a safe tune of 9psi on it running 200rwkw.

The tuner said I needed to get new coilpacks so Splitfires are on the books.

However, the past few days something weird has started happening. I let my car warm up, start driving ITS FINE. Then when I'm in 4th gear on a flat road or going down hill and i press the accelerator ever so slightly, I'll get a few sputters, but if I drop the gear and give it it will come on boost no worries.

Anyways, so yesterday I'm driving down the highway and im in 4th gear and i try to accelerate. My car starts sputtering so bad that I can't even get it to move. So i have to pull over and I cant get the revs over 1500 RPM because its sputtering so bad even when im reving it on the spot.

I let my car sit there for a minute or two, take off and its fine, however it begins doing it every now and again after a couple of minutes so I left it at my grandmas house and got a lift.

I picked up my car after a couple of hours and it was fine on the cold start, driving perfectly, but as soon as it warmed up it began doing the same thing.

It eventually got so bad that i pulled over and the check engine light came on and it began searching for idle and every time i would rev it, the revs would drop so low it almost stalled until finally it did stall.

I got it home driving 40 km/h in 4th gear not taking it over 2000RPM. LEft it over night.

I started it up this morning and gave it a few revs and the problem isn't there. So i'm assuming it only happens when the car warms up which leads me to believe it is the coilpacks. However, I want to be 100% sure before I go spend $600 on splitfires.

Cheers

Chris.

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are you still using afm???

could be a prob with the solder in the afm.

happended to me. + the car would cut out.....

good luck

Hey mate

Yeah I'm using a Z32 ...

But if that was the case, how come it worked fine for the first 2 weeks?? :S

i do have alot of missfire and the head of my engine gets really really hot i don't know if this is normal?

Edited by LI51CA

Z32 AFM 2nd hand by any chance? If so there is a better than even chance it may need re-soldering.

CRC Red Urethane Seal Coat for your coil packs is the cheapest fix. Click the link below for more info.

http://www.skylinesaustralia.com/forums/in...t&p=4540665

I started it up this morning and gave it a few revs and the problem isn't there. So i'm assuming it only happens when the car warms up which leads me to believe it is the coilpacks. However, I want to be 100% sure before I go spend $600 on splitfires.

Hey mate, have a read through my misfire resolution thread before buying the coilpacks. In my case the Crank Angle Sensor was stuffed, which caused misfiring and lack of power from 4000 rpm onwards.

Ideally you could look into borrowing a set of coils from someone for a day and testing with those both cold and warm to see whether they fix the problem or not.

Cheers

mate if you read my post... its only running 9psi because i need new coils because anything above 14psi it breaks down... the pump is fine for 500hp my mate has a similair set up and no porblems...

I'm not replacing anything

GT35R + 200rwkw + walbro pump

something doesn't add up

please replace the fuel pump and check the AFR's

  • 3 months later...

hey guys,

i have spent almost all day reading up different threads to find something similar to what im dealing with and this is the closest so far.

i recently had some pretty big leaking from my injectors on my 1990 R32 GTR (so bad it was actually dripping from all the way down at the bell housing under the car), after changing out the sels n rings the two problem injectors where still leaking. Luckily a friend had some spare working GTiR injectors which he sent me for FREE!! (anything free is just awesome) haha. I swapped out the two leaking ones and everything seemed to be good, no leaking or fuel smell.

Took the car for an hour and a half run to gold coast from northern NSW and it was running quite smooth. spent a night up there having a few "spirited" drives and returned the next day. while returning back down d coast i noticed a few times that there didnt seem to be full power under the accelerator but nothing much and once i put my foot down it would start pulling like always. 30-40 minutes later near byron bay the car started spluttering and struggleing so bad i could barely get it to accelerate and with my foot in a consitatnt position it was as if i was bliping the throttle, after bout 30secs-1min of me freaking out and trying to get to a spot to pull over the problem cleared and the car seemed back to normal. so i keep driving keeping a very watchful eye on everything and it seemed fine for a while. i then noticed that when it felt a bit low on power again a few times while cruising, & even while travelling around 80km on the highway, if i put it in neutral and didn't accelerate the car would completely stall even once bring up the check light for a few seconds while still moving along. a bit firther down the road and it started spluttering n freaking out again to the point where i could barely accelerate, or even keep the revs up. again after another 30-1min it returned to running fine.

i pulled over once i got to a nice big carpark to check what i could see and nothing looked wrong and car was running fine again, so took it home and parked it.

I have read to check and clean the AAC and IAC, which i will be doing today, and also that it could be a crankangle sensor, or AFM's, or O2 sensor, or engine temp sensor, or faulty coil packs, or even ECU.

can anyone help who may have experienced something similar. i no this is a long post and am sorry to jack the thread but i am at wits end and need to drive the car 10hrs down to sydney in a few day and dont really want this to happen again. i am going to try to look at all these things but currently dont have a scan tool or much time so i want to try and narrow down my search.

thanks heaps guys.

  • 4 months later...

hey guys,

i have spent almost all day reading up different threads to find something similar to what im dealing with and this is the closest so far.

i recently had some pretty big leaking from my injectors on my 1990 R32 GTR (so bad it was actually dripping from all the way down at the bell housing under the car), after changing out the sels n rings the two problem injectors where still leaking. Luckily a friend had some spare working GTiR injectors which he sent me for FREE!! (anything free is just awesome) haha. I swapped out the two leaking ones and everything seemed to be good, no leaking or fuel smell.

Took the car for an hour and a half run to gold coast from northern NSW and it was running quite smooth. spent a night up there having a few "spirited" drives and returned the next day. while returning back down d coast i noticed a few times that there didnt seem to be full power under the accelerator but nothing much and once i put my foot down it would start pulling like always. 30-40 minutes later near byron bay the car started spluttering and struggleing so bad i could barely get it to accelerate and with my foot in a consitatnt position it was as if i was bliping the throttle, after bout 30secs-1min of me freaking out and trying to get to a spot to pull over the problem cleared and the car seemed back to normal. so i keep driving keeping a very watchful eye on everything and it seemed fine for a while. i then noticed that when it felt a bit low on power again a few times while cruising, & even while travelling around 80km on the highway, if i put it in neutral and didn't accelerate the car would completely stall even once bring up the check light for a few seconds while still moving along. a bit firther down the road and it started spluttering n freaking out again to the point where i could barely accelerate, or even keep the revs up. again after another 30-1min it returned to running fine.

i pulled over once i got to a nice big carpark to check what i could see and nothing looked wrong and car was running fine again, so took it home and parked it.

I have read to check and clean the AAC and IAC, which i will be doing today, and also that it could be a crankangle sensor, or AFM's, or O2 sensor, or engine temp sensor, or faulty coil packs, or even ECU.

can anyone help who may have experienced something similar. i no this is a long post and am sorry to jack the thread but i am at wits end and need to drive the car 10hrs down to sydney in a few day and dont really want this to happen again. i am going to try to look at all these things but currently dont have a scan tool or much time so i want to try and narrow down my search.

thanks heaps guys.

Was driving my R33 GTR from sydney to melbourne, this has also happened to me, was cruising for about 3 hours then the symptoms above started happening, hesitation misfire etc, pulled over drove and again couple mins later and the car was fine,

It seems to come and go. im leaning towards coilpacks or AFM, anyone have an idea? don't want to be throwing parts into the problem trying to find a fix

Pull the top cover off your afms and resolder the joints. My car had pretty much identical symptoms and thats what caused mine.

The reason they run fine cold is because the solder joints still contacted well enough to not lose signal but when a bit of heat gets into it the dry joints open up and go open cct.

If i get a chance at work tommorrow ill gut my spare one and make up a tutorial on fixing them, its fairly simple and on takes bout 20 min.

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