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actually was doing some test's on the free way last night

if i boot it it will stick @ 4.5 - 5k rpm.

if i ease it into the throttle it will go all the way to 8k without any problems at all..

im thinking fuel pump?

im thinking your coil packs are arching out.

is it a backfire or a boost miss?

backfire is where the engine has two much fuel put into it and it expels it in one burst out your exhaust.

could be caused by:

1. bad fuel

2. shit in the bottom of your tank if you had low amount of petrol

3. running too rich

but im leaning more towards checking your coil packs

I'm having the exact same trouble on my 33 gtst at the same revs, 3inch exhaust is the only mod. Replaced sparks with new standard coppers which seemed to clean it up a bit but soon after the problem was back, most of the time it's worse when the car has warmed up. Been thinking about getting some of those hks iridium plugs that can withstand more heat but at 19 bucks each it would be nice to know before hand if it's gonna help. Maybe check the gaps on your current plugs to make sure they haven't blown out and are in ok condition?

It's sort of a rapid "pop pop pop pop" coming from the exhaust like unburnt fuel is being dropped in to it, engine hesitates badly which causes the whole car to shake around a bit.

I'm having the exact same trouble on my 33 gtst at the same revs, 3inch exhaust is the only mod. Replaced sparks with new standard coppers which seemed to clean it up a bit but soon after the problem was back, most of the time it's worse when the car has warmed up. Been thinking about getting some of those hks iridium plugs that can withstand more heat but at 19 bucks each it would be nice to know before hand if it's gonna help. Maybe check the gaps on your current plugs to make sure they haven't blown out and are in ok condition?

It's sort of a rapid "pop pop pop pop" coming from the exhaust like unburnt fuel is being dropped in to it, engine hesitates badly which causes the whole car to shake around a bit.

yeah, one thing to do would be to get a mate to drive from behind in your case and watch while it happens for smoke out the exhaust.

in your case but nicrwks, yours sound more along the lines of a boost missfire.

couple of things:

1: what rpm is this happening at?

2: what fuel is in your car?

3: how much boost you running?

couple of things: 

1: what rpm is this happening at?

2: what fuel is in your car?

3: how much boost you running?

1. Starts at 4.5-5k rpm right through to redline

2. bp ultimate

3. 7psi (no 2 stage)

Current sparks are NGK BKR6E

Alexxs: do you get the same popping sound around this rpm?

Edited by nicr4wks

yeah my issues start at about 5k rpm, its not a boost leak, ive checked that out..

im going to replace the fuel pump tomorrow, (tried today and fuel tank as full DURRR WHU?!?! im a retard lol)

and doing sparkies tomorrow along with taping up the coil packs i guess.

car hasn't been boosted stock 7psi

its frustrating sigh :teehee:

*edit*

im about 1/3 of my way through a tank of 98 with some injectors clears in it.

always run 98, vpower or bp ultimate.

Edited by Alexxs

Sorry for hijacking the thread. I've got back firing issues as well.

Mods:

Yellow Jacket Coil Packs

Plugs gapped to 0.8mm

3inch turbo back exhaust

Pod Filter

FMIC

I'm also still running the standard factory solenoid. Somehow when I'm flooring the throttle, I get up to 10-11psi of boost.

Anwyay, when I'm in 1st or 2nd gear and I back of the throttle at about 5000-6000rpm, I can hear back firing. There's no smoke coming from the exhaust.

Can anyone diagonse this?

Sorry for hijacking the thread. I've got back firing issues as well.

Mods:

Yellow Jacket Coil Packs

Plugs gapped to 0.8mm

3inch turbo back exhaust

Pod Filter

FMIC

I'm also still running the standard factory solenoid. Somehow when I'm flooring the throttle, I get up to 10-11psi of boost.

Anwyay, when I'm in 1st or 2nd gear and I back of the throttle at about 5000-6000rpm, I can hear back firing. There's no smoke coming from the exhaust.

Can anyone diagonse this?

if it only happens when u back off the throttle id say ur running rich. really rich or ur fuel pump / injectors need a clean / replace.

hey everyone.. ive got a bit of a smiler problem but 10 times worse to the point that its not drivable :laugh:

about 3 days ago had my car parked outside a mates house.. and it was hell stormy weather.. anywayz i went to start the car it started then stalled.. so then i tried again this time it stayed on. but then as i went to drive off it stalled again. i noticed that every time i pressed the accelerator heaps of black smoke came out the exhaust which i know means its running rich.. but this wasnt just the usual lil bit of black smoke it was to the point where u could smell fuel and yor eyes would burn.. this obviously means that theres heaps of fuel that isnt getting burnt.

anyways i managed to get the car home and i took the coil packs out to look at them and there was water where the spark plugs are (decent amount). i drained it all out.. dryed the coils and put it back together started the car and its still doing the same thing. then i took the spark plugs out them and found that 3 of them were wet from the fuel.

this is obviously an ignition problem any ideas how i can narrow it down to wot part of the ingition system is stuffed? whats the best way to check the coils and the lil modual that sits on top of the plastic cover on at the back end of the engine etc??

help please!!!!!

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