boost problem

[andy-m]

i have notcied every so often, the car just doesnt accelerate like it normaly does at 50mph+
It's an intermittant thing that doesnt happen that often, but today it did it and I notcied my boost would not go above 0.4bar. it didnt matter if I was full throttle or if I backed off a bit, it stayed at 0.4bar untill I took my foot off the gas enough for it to drop.

it's done it on my current DV and the OE one. I vaguely remember reading something about gearbox wiring/neutral switch possibly causing a drop in power. anyone got any ideas ?

[Scott.T]

Give the boost control solenoid a clean, it sounds like it's getting stuck and not bleeding air away from the actuator as it should.

[andy-m]

Carb cleaner ok?

[Scott.T]

Originally Posted by andy-m

Carb cleaner ok?

Yep....

[mr noisy]

I also have the same thing going on in my classic as it stands, Keep getting told diffrent things it could/will be EG spark plugs, coil packs, MAF, boost solinoid, i dont know where to start, the car still drives fine with no misfire ect just reaches 8psi and thats it then you can get down the road and it goes fine @ 15/16psi 1st & 2nd always are the best gears as even when its @ 15/16psi in 3rd upwards it feels little slow but guess its what ive been through in the past, now it would be nice to try some other parts as test dummies to see what it does before i start spending out loads on things i dont really need, Hope that maybe sumbody can help ??

[andy-m]

unless it splutters under full acccelleration, usualy around 4000rpm, it's not co-ildpacks or plugs. I had that propblem on my old scoob.
havent had a chance to clean my boost solenoid yet but a long 200 mile round trip today leads mne to believe that silver is right, it's my boost solenoid.

from cold start and running after a while, it's fine. it seems to be when I am in slow traffic or stationary for a while that the problem then occurs and I don;t get full boost/ once i;m on the moove for a while an dit cools a little, I get my full 1.1bar boost again.

First bit of decent weekend weather and I will be out there cleaning the solenoid

[bonner]

Originally Posted by andy-m

unless it splutters under full acccelleration, usualy around 4000rpm, it's not co-ildpacks or plugs. I had that propblem on my old scoob.
havent had a chance to clean my boost solenoid yet but a long 200 mile round trip today leads mne to believe that silver is right, it's my boost solenoid.

from cold start and running after a while, it's fine. it seems to be when I am in slow traffic or stationary for a while that the problem then occurs and I don;t get full boost/ once i;m on the moove for a while an dit cools a little, I get my full 1.1bar boost again.

First bit of decent weekend weather and I will be out there cleaning the solenoid

my classic had this same issue!! then it started to die on junctions! the car ran 100% untill in went into a supposed tuner garage! had a hdi fmic fitted and then my problems began didnt ever get to the bottem of it on idle it cought up black carbon smoke running lumpy, running hot as you say in slow traffic then putting your boot down the motor didnt want to no unill it was cool

[mr noisy]

Which one is the boost solinoid? As there is 2 items on inner with with 2x vacume pipes on each

[andy-m]

I think it's number 9 as number 7 does not have any electrical connection:-

[Scott.T]

No. 9 and it will be a 3-port on pre96 and 2-port on 97>

The MAF on the 1992-1996 can also cause boost to limit when it starts to fail.
You don't see any CEL warning it just limits the boost. Sometimes you can fix it with a clean with carb cleaner and cotton bud.

[mr noisy]

Should brake/carb cleaner run in one and out the other hole? Also does anybody have a orange sticker maf? Or/and spare boost solinoud i could try

[Scott.T]

Originally Posted by mr noisy

Should brake/carb cleaner run in one and out the other hole? Also does anybody have a orange sticker maf? Or/and spare boost solinoud i could try

If you can, stick 12V to it so you can open/close the solenoid. Don't spark the connections too much though as carb cleaner has a habit of igniting.
Also clean through the pipes that run from and to it.

[mr noisy]

How do i work out which is posative & negative?

[andy-m]

positive is usualy red and negative is usualy black

[mr noisy]

Also is it safe to put the blower through it of the air line or will it be to much and damage it?