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hey guys,

recently i had problems with my coil packs as it seems to pop/fart/missfire when i hit +3k rpm then found that my 3 of my coil packs had hairline cracks so i epoxy-ed it and changed my plugs since the oppurtunity was there. problem solved able to hit +4k rpm no problem but today I had the itch to launch but noticed that when i 80% full throttle it boost then cuts off/jerks hard then boost again at around 5k rpm....is this a coil pack problem? fuel starve? or voltage starve? or u what? no problem when i accelerate normally n hit boost but full throttle it does that.

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https://www.sau.com.au/forums/topic/301724-need-serious-help-here/
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+1 for asking what boost you are running.

i'm guessing you still have the stock ecu and your boost is up around 13psi, yes? if so, you are hitting the ecu boost protection. basically when the AFM sees too much airflow for a given point in the load/rpm scale it backs off

hey guys,

recently i had problems with my coil packs as it seems to pop/fart/missfire when i hit +3k rpm then found that my 3 of my coil packs had hairline cracks so i epoxy-ed it and changed my plugs since the oppurtunity was there. problem solved able to hit +4k rpm no problem but today I had the itch to launch but noticed that when i 80% full throttle it boost then cuts off/jerks hard then boost again at around 5k rpm....is this a coil pack problem? fuel starve? or voltage starve? or u what? no problem when i accelerate normally n hit boost but full throttle it does that.

supporting mods i have is FMIC, exhaust system, Turbosmart boost tee controller set at 7clicks (apparently suppose to be equivalant to 7psi not sure), stock ecu, stock turbo.....

today took a better look at my boost gauge n it hits 1.3 bar which is strange when i set my controller at 7...hmm then watched the stock boost gauge(dash gauge) noticed that it hits +7 then cuts so now the problem is defined....i reduced the boost to 4 clicks but still does the same thing...turned it off completely and still hitting +7 .,,,its as if the turbo is boosting by it self or somethin....any ideas?

lol wow - dude, stop touching you car. You are lucky you have not blown it up, and i am not saying that in a joking sense, im deadly serious.

7 "clicks" will be 7-10psi above the BASE pressure. Factory you run 7psi, so +7-10PSI more and you are talking 16-17 through the factory turbo and then some... no surprise you are hitting 1.3 bar (absurd pressure)

1. You are hitting Rich & Retard

2. You are basically putting the turbo in to absolute danger zone running that much boost - it will disintergrate. Anymore than 11-12psi is a no-no.

3. +7 is the MAX the factory gauge shows, this is roughly 14psi

4. If the turbo fails, it CAN kill a motor. Especially @ that level of boost, and compressor speeds etc, bad bad bad shit can happen.

Take it to a professional for gods sake - seriously.

You also make no mention of a fuel pump, this is also ridiculously dangerous.

I'd be highly surprised if some form of damage has already been done.

hey guys,

recently i had problems with my coil packs as it seems to pop/fart/missfire when i hit +3k rpm then found that my 3 of my coil packs had hairline cracks so i epoxy-ed it and changed my plugs since the oppurtunity was there. problem solved able to hit +4k rpm no problem but today I had the itch to launch but noticed that when i 80% full throttle it boost then cuts off/jerks hard then boost again at around 5k rpm....is this a coil pack problem? fuel starve? or voltage starve? or u what? no problem when i accelerate normally n hit boost but full throttle it does that.

lol,sorry for laughing but i know a guy like you who decided to fiddle with his boost when you have no idea what your doing.he decided he wanted to run his car on 20psi on a pretty much stock r33 and blew it up.

i bet your car is damaged from this and if it aint showing now it will soon.

As long as Nissans little EGT (exhaust gas temperature) sensor is doing its job the engine shouldnt have taken to much internal damage, the turbo though can easily been heavily damaged.

I see you've got a aftermarket exhaust system, have you still got the EGT connected? It looks like a small lambda sensor, placed right before the cat.

What factory EGT sensor?

The only sensor there is after the turbo is the O2 sensor, and the Cat temp warning sensor. The cat temp sensor being plugged into the cat itself.

Is it NOT a EGT sensor in the true sense as it does not have anything to do with the ECU.

All it does it flash up a dash warning light for CAT overheat.

just to add to this thread,

my problem is similar... although i only get it in 2nd gear on full throttle... hits about 3500rpm, miss fires then full boost again... any other gear on full throttle there is no missfire.. running stock boost

(mods 3" exhaust, turbosmart boost tee, greddy oil cooler)

What factory EGT sensor?

The only sensor there is after the turbo is the O2 sensor, and the Cat temp warning sensor. The cat temp sensor being plugged into the cat itself.

Is it NOT a EGT sensor in the true sense as it does not have anything to do with the ECU.

All it does it flash up a dash warning light for CAT overheat.

I could be wrong i guess but as i've been told earlier the ecu change the timing if it runs to lean, this 'cause of the cat temp sensor and knock sonsors giving a to high value.

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