HELP: sudden gain in boost although it was cutting out????????????????
06 July 2003, 05:53 PM
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Right car is me MY97 UK car with no serious engine mods or owt only real potential boost/performance related bits are blitz nurspec centre & back box (standard dp) & dump valve 
Now previously with me defi HUD boost gauge i had achieved a max boost of 1.04 & this was when i had an ITG panel filter on, since had this replaced by standard panel filter at last service, hadn't noticed anything above 1 bar since.
However driving up motorway to a meet today when i planted my foot on the gas i noticed it shot up past 1 bar, after noticing this i tried again with sustained gas went upto about 1.15bar & then held at 1.14bar However it then started cutting out totally after about 2 seconds at this boost for a split second & then cut back into 1.14 or so again for a few secs & repeated...... Only did this a few times as it was v strange/worrying
On stopping to pick up some more peaps & popping bonnet nowt noticably looose or bizarre, other than a light bit of smoke from drivers side of engine which i already know to be a slightly leaking rocker gasket cover thingamy so surely unrelated
So carried onto meet with no excess accelerator use.....
On the way back i tested again & it seemed to now go upto around 1.12bar at most & hold this without any cutting out i only held this for 5 sex or so as i didnt fancy taking the pea untill i knew what the story was?
So any ideas why i have suddenly got extra boost & what the hell was the cutting out? IE is there anything going wrong that might cause this?
Just a gain in boost seems v weird
No changes in fuel or owt used always run on optimax & so er im flat outa ideas
HELP paranoia kicking in
Si
Now previously with me defi HUD boost gauge i had achieved a max boost of 1.04 & this was when i had an ITG panel filter on, since had this replaced by standard panel filter at last service, hadn't noticed anything above 1 bar since.
However driving up motorway to a meet today when i planted my foot on the gas i noticed it shot up past 1 bar, after noticing this i tried again with sustained gas went upto about 1.15bar & then held at 1.14bar However it then started cutting out totally after about 2 seconds at this boost for a split second & then cut back into 1.14 or so again for a few secs & repeated...... Only did this a few times as it was v strange/worrying
On stopping to pick up some more peaps & popping bonnet nowt noticably looose or bizarre, other than a light bit of smoke from drivers side of engine which i already know to be a slightly leaking rocker gasket cover thingamy so surely unrelated
So carried onto meet with no excess accelerator use.....On the way back i tested again & it seemed to now go upto around 1.12bar at most & hold this without any cutting out
i only held this for 5 sex or so as i didnt fancy taking the pea untill i knew what the story was?So any ideas why i have suddenly got extra boost & what the hell was the cutting out? IE is there anything going wrong that might cause this?
Just a gain in boost seems v weird
No changes in fuel or owt used always run on optimax & so er im flat outa ideas
HELP paranoia kicking in
Si
06 July 2003, 07:30 PM
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The cutting out is fuel-cut due to too much boost pressure. If the ECU sees a certain pressure for a few secs it cuts the fuel to protect the engine - this is normal.
You need to work out what's causing the boost to go too high, first thing to check is the pipes between compressor outlet, wastegate and boost solenoid. Make sure they are all secure and no cracks etc. Once you get this sorted the car won't fuel-cut again.
You need to work out what's causing the boost to go too high, first thing to check is the pipes between compressor outlet, wastegate and boost solenoid. Make sure they are all secure and no cracks etc. Once you get this sorted the car won't fuel-cut again.
06 July 2003, 08:03 PM
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This has been happening to me lately.
Mr Banks and I found the hose from Boost solenoid to Turbo to be holed.
However this was for reasons specific to my car.
Mr Banks and I found the hose from Boost solenoid to Turbo to be holed.
However this was for reasons specific to my car.
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