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slight boost spikeing prob when warm
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Old 23 Apr 2007, 06:12 PM   #1 (permalink)
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slight boost spikeing prob when warm

Hey people,

My car runs great from turn over, i let the engine warm a little, and whe I put my foot down.......it flies, pushes head back into seat etc.................... but when it gets hot/warm, I seem to get a spike problem, It overboosts to about 2bar (usually to 1.2 as ppp), then back down, causing the boost to cut off............... car still runs fine, ticks over fine, no noises.... no error codes..... no air leaks as i can see...
tried resetting ecu.

Could this be a maf problem? I have changed the maf before, but there was no intermittent fault, it just ran like a bag od crap..but also didnt give a maf error code at that point either,

Any suggestions would be great!.......... rolling road wouldnt be an option at this point as nearest one is about 50 miles away.

Too let you know its been dogin this for about 6 months, but only latley had time to sort things out
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Old 23 Apr 2007, 06:13 PM   #2 (permalink)
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mmm strange, could be any number of things, have you tried resetting the ecu?
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Old 23 Apr 2007, 06:14 PM   #3 (permalink)
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Whats the specs on your car? Mods? I know the newer Scoobs will boost spike if you are running exhaust, intake etc.. without fuel management.
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Old 23 Apr 2007, 06:18 PM   #4 (permalink)
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as per my av, its turbo 2000, ppp, magnex system........ bailey dump valve,

NOthing else.
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Old 23 Apr 2007, 06:19 PM   #5 (permalink)
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prob worth trying a ecu reset then if not gonna have to take it to be looked at i'm afraid, so many different things it could be you could spend a fortune chasing it round for something as simple as a sensor
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Old 23 Apr 2007, 06:21 PM   #6 (permalink)
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prob worth trying a ecu reset then if not gonna have to take it to be looked at i'm afraid, so many different things it could be you could spend a fortune chasing it round for something as simple as a sensor

MMmm... tried ecu reset, nothing........

Im really thinking its a maf sensor... but would 70 for new one.........
I changed the knock sensor about 6 months ago too.
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Old 23 Apr 2007, 06:26 PM   #7 (permalink)
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think you need to get it looked at, wether a laptop to check out the ecu or a rr run to check it. be best optiona nd prob save you some money
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Old 23 Apr 2007, 06:27 PM   #8 (permalink)
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think you need to get it looked at, wether a laptop to check out the ecu or a rr run to check it. be best optiona nd prob save you some money
k thanks for your help anyway
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Old 23 Apr 2007, 06:30 PM   #9 (permalink)
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k thanks for your help anyway
no probs, sorry i can't be more help, as you say it could be a maf sensor issue, could be another sensor, could be a boost creep issue, could be a split pipe somewhere
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