Engine is cutting out on standard boost

[Scooby_Steve]

Hi,

I've got a SII skyline with just an exhaust (full). With this exhaust it was running 9psi (without upping the boost). I then put in a bleeder valve ,(GFB brand) and ran it at 10psi. It was running perfect on all gears without any "cutting out". Then the next day it started cutting out very often. I have since removed the bleeder value and the engine is only running a measly 7psi (with the exhaust) but still cuts out... Does anyone have any ideas what is wrong and maybe what i can do to fix it? any help would be much appreciate it.

thanks,

Steve

[xr8eater]

gap the plugs down to 0.8. my s2 did that till i gapped my plugs down also it will help if you get an apexi afc to stop fuel cut

hope that helps

[Scooby_Steve]

Hi,

Thanks.. I'll give that a go..

[Scooby_Steve]

Hi,

Just remembered that I'm using all the standard plugs etc that was in the car before i added the bleeder valve... So any more help would be great. Thanks

steve

[Kinell]

Check your battery terminals

[Neosaber]

Also check the coils....mine was cutting out.....plus mine still cuts out after 12psi...must be te stock ecu having a brain fart

[Z00MxRACING]

also u may wanna get ur actuator (wastegate) leak tested ... coz if that is leaking it will boost normally at a certain rpm then will suddenly cut or jerk ar higher rpm ... (cut out)

juzz get the tube from the actuator going to the IC piping and let it blow into the tube with a air compressor and listen for air leak .. if its tight (the air blowing) that means your actuator is still good ...then back to the square boards..

hope dat helps..

[Scooby_Steve]

Hi Guys,

Thanks so much for your help.. Will try some of the advice you guys have given..once again thanks

[Scooby_Steve]

Hi,

I have tried what you guys have said but still no luck.... It's taken me so long to repsond as I was trying to put a cooler in.

I forgot to mention that the jerking happens from about 3000rpm to 7000rpm (roughly when the turbo start to spool) in all gears.

Any more help or opinions are much appreciated. Thank you.

Steve

[henzie]

you Ecu Computer has blown get it fixed or buy a new one =]

i had that problem before !

[Al]

you Ecu Computer has blown get it fixed or buy a new one =]  

i had that problem before !

Let’s all just jump to the worst scenario and start throwing money away.

Check all vacuum lines to and from the turbo, plenum, etc. What year is your car? This can also be caused by coils, or the igniter pack. B4 buying big dollar items I would personally go to a good import mechanic and give them a go at finding the problem.

[Scooby_Steve]

Hi,

I've read the post about the misfiring.... I'd say my car is in the same scenario.. I havent yet looked at the coils but will be doing so.

I'm reluctant to say its the ECU because the boost was only changed to 1 psi more than what the mods had given it (ie exhaust gave it 2 psi more to make it run total of 9psi and then i winded it up 1psi to make it 10psi) and that when the problem started happening. Thanks for you input.

I'd like to take it to a good mechanic but there arent a great deal of mechanics in the area i live in that would have probably worked on imports....

Lastly, my car is a SII R33 Skyline GTST.

Once again thanks again.

Steve

[Zahos]

i also had this happen the way you are describing once, and turned out to be oxidation on the coil packs. When I pulled them out, one of them was green where the coil pack makes contact with the spark plug. Cleaned them all with WD40 and car has never run smoother. Many people I've spoken to overlook this point.

Cracked coils usually dont make a big difference on standard boost, but if you are getting it as low as 3000 rpm, I definately suggest looking for any oxidation.

[Scooby_Steve]

Hi,

thanks for your input.. I'll look at the coils this weekend.

[Keeper]

talk about post-necromancy, did you solve this?

is it easy to **** an ECU?

[benl1981]

I'm getting a miss right when it comes on boost about 3000rpm, actually More like just a hesitation and have also felt a cut at about 3000rpm in 4th. Put new plugs in at 0.8 gap - no change

Anyway. I am running the car without the sparkplug cover on, I can see arcing on 5 if not 6 of the coils. So I'm hoping this is the problem. You can only see it if it is VERY dark and helps if the car is warm...

I thought it was only No.1 coil but after a closer look - ALL of them

I was thinking it was an ECU cut out. But I don't think so anymore. I'll let you know once I get new coils or fix these ones.

[neo32]

dude u done a block test my car was like this then did block test turns out slightlig lifted head gasket

hop this helps

[hanyou]

my car is doing this too.. it started jus little jabbs every now and then. i realised it usually happend on cold nights too.. all i can say is mine went worse as days went on. if u find the problem let me know too

[Team_Stable]

dont know if this has been said but, check the fuel pump etc. the engine might be gettin starved of fuel when the turbo comes in, hence the boost/fuel cut thing.

[Scooby_Steve]

Hi,

I found that by taping the coils, my hesistation, backfiring goes away so I know i've got cracked coils however, if in 4th or 5th gear I and decide to overtake, sometimes it will just cut right off and then go again so i dun know whats going on there.