Author Topic: Boost Problems.  (Read 1885 times)

Offline Alan16ac

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Boost Problems.
« on: 18 January 2012, 21:14 »
My car holds boost at 12 PSI upto 4300 RPM, when I pass 4300 RPM, it suddenly drops with a jerk of the car to around 7 or 8, it then judders around up and down between 7 and 9 as if it's trying to pressurise but can't hold it's boost?

Any ideas why this could be?
It's got a blow off valve which was on it when I bought it, could this be a problem?

Offline Wazzzer

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Re: Boost Problems.
« Reply #1 on: 18 January 2012, 21:26 »
what engine code? Most don't like blow off valves...


1999 1.8T: R-Tech remap - 225bhp/256lb/ft : K03s : THS FMIC : THS PCR pipe : 2.5" stainless exhaust : THS FR3 Engine mounts : G60/VR6 clutch : Calibra Yellow injectors : VR6 MAF : Devils Own WMI : Forge 007p : Carbonio CAI : Leon Cupra R Brembos : FK AK Street coilovers : Votex skirts : Anniversary front : click ---> http://www.golfgtiforum.co.uk/index.php?topic=92175

Offline Wayne

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Re: Boost Problems.
« Reply #2 on: 18 January 2012, 21:28 »
I suspect the blow off valve is causing it to drop into limp mode.

Offline Alan16ac

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Re: Boost Problems.
« Reply #3 on: 18 January 2012, 21:32 »
It's a 1999 AGU.
It doesn't stop me from revving all the way to the red line though, which I thought limp mode did?
I don't rev to the redline though as there's no power after 4300, as there's no boost!

Offline daz veedub

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Re: Boost Problems.
« Reply #4 on: 18 January 2012, 21:35 »
have u checked boost pipes for leaks

ran a faultcode reader ?

ditch the blow off  :wink:

get forge/awesome 007p  :smiley:

Offline Alan16ac

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Re: Boost Problems.
« Reply #5 on: 18 January 2012, 21:51 »
have u checked boost pipes for leaks

ran a faultcode reader ?

ditch the blow off  :wink:

get forge/awesome 007p  :smiley:

How easy will it be to swap the BOV for the Forge 007p?

I'll run the OBD reader on it tomorrow, only a cheapy that tells me codes though.

Offline Alan16ac

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Re: Boost Problems.
« Reply #6 on: 20 January 2012, 21:40 »
Here are the fault codes on my OBD reader;
16518
16519
16487
16706
Gonna try and find what they are!

Offline Alan16ac

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Re: Boost Problems.
« Reply #7 on: 20 January 2012, 21:44 »
Here are the fault codes on my OBD reader;
16518
16519
16487
16706
Gonna try and find what they are!

16518 P0134 O2 Sensor Circ.,Bank1-Sensor1 No Activity Detected

16519 P0135 O2 Sensor Heater Circ.,Bank1-Sensor1 Malfunction

16487 P0103 Mass or Volume Air Flow Circ High Input

16706 P0322 Ign./Distributor Eng.Speed Inp.Circ No Signal - think this one means the crank sensor which is sorted.

Offline james2

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Re: Boost Problems.
« Reply #8 on: 20 January 2012, 21:51 »
Could just be the wrong spring in the blow off valve. I had no problems with a blow off valve on a AGU. I had no fault codes ,even when standard dv died and stayed shut. You will need to sort them codes out after you sort your boost pipes out and replace blow off valve with a 007 .Then delete the codes and see what ones pop back up.
AGU 1.8T. Mods done: R32 front bumper, turborev smic, ngk platinum spark plugs, uprated pancake pipe, demon motorsport boost hoses, forge 007 dv, forge engine cover, r-tec stage 1 map ,home made cold airfilter ,run on 98 ron fuel and castrol edge 0w 40 oil. Advanti racing alloys.

Offline Alan16ac

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Re: Boost Problems.
« Reply #9 on: 20 January 2012, 21:54 »
Could just be the wrong spring in the blow off valve. I had no problems with a blow off valve on a AGU. I had no fault codes ,even when standard dv died and stayed shut. You will need to sort them codes out after you sort your boost pipes out and replace blow off valve with a 007 .Then delete the codes and see what ones pop back up.

I think the 1st 2 codes maybe because of it's "special cat"  :rolleyes: