PhilA

Can anyone help. The engine seems a bit jerky/hesitant especially between 2500-3000 RPM. If you try and drive the car nicely at a steedy speed with the revs at 3K RPM it's very noticeable (boost problem??). Just had MAF and Wastegate control valve changed as the problem was much worse before. The MAF improved it alot as the MAF was nackered, but the wastegate valve thing didn't do anything. Any ideas please..

Shropshire-Guy

Had same problem phill myself after clutch change. Sugest you go back and check all hoses, especialy the big one from the intercooler to throttle body (about 4in in diameter) undo clips, check pipe and reposition it and tighten up again. i couldn,t get it tight enough with screw driver so used 8 mm socket on jubilee clips, be carefull not to **** them up thou. Could be also boost valve that may have something shxxxy in it. My guessing on of the hoses aint tight thou bud, check and recheck all of them.

steve

PhilA

The boost valve is the wastegate thingy??

Forgot to mention when I put my foot on the clutch when I'm stopping, the revs drop very low and the car almost stalls but it doesn't.

Shropshire-Guy

Still check hoses mt8. Before you go pulling anything else apart. Thats all hoses including ones on Boost valve

trance

Check idle sensor for crap. Give it a good clean. I would also give your boost solenoid a clean. Would'nt hurt anyway!!.

PhilA

to ask a silly question, where exactly is the idle sensor? any pics? would be easier if I had a haynes manual, they were useful for some things.

trance

It should sit right on the middle of the engine bay, up near the intercooler. You will see the connection plug to it.

CEL

iTrader: (1)

PhilA.. the symptoms you describe are exactly the same im getting with my 98 UK turbo... i would appreciate you letting me know if you do find a solution to the problem.

Thanks

Chris

P.S, mine has stalled a few times when pulling up to a junction.

PhilA

Some people suggest it is my Blitz BOV dump valve that needs adjusting so I'm trying that. If that fails I may put the OEM one on and see if the problem goes away. Alternatively I have just found out how to read ECU codes so I may check to see if the ECU is reporting a problem.

Do you have a dump valve on yours?

CEL

iTrader: (1)

Phil.. yeah i have a blitz dump valve too... its a fairly old one though.

Did you solve the problem yet?

PhilA

Adjusted it yesterday, better but not fixed. I've just adjusted it somemore now, about to test drive it.
Apparently, the adjuster screw on the end should be nearly all the way in on scoobies?
How long have you had your on? Has your car always done this? Do you have a standard one to test with (only takes 5 minutes to swap over). I need to buy the original hoses to test my OEM one (never got any with the car).

Let me know.

phil

CEL

iTrader: (1)

I tried turning the adjuster too when i first put the valve on. Originally it had a bailey dump valve fitted but the spring broke. Have to say i didnt get this problem with the bailey valve.
Having said that i cant figure why the dump valve would make the engine hesitant during acceleration.

Think im going to adjust the valve again so the spring has more pressure on it... i'll let you know what happenens... the other thing that has been suggested is a knackerd maf sensor

Cheers

Chris

PhilA

You may have a broken MAF as well but thats not the entire problem as I changed mine last week (it was broken anyway).
If you look down the dump valve trumpet it looks like the DV part opens during acceleration. Is it meant to do this? I thought it was only meant to open when you lift off the throttle?
Are you saying this started when you fitted the Blitz DV?
My car is better but I think I'm going to adjust the screw fully in at the weekend. If that doesn't fix it the Blitz is coming off. I'll test with the OEM then I'll sell the Blitz and get a different brand.

CEL

iTrader: (1)

I was thinking about changing the MAF sensor but im not sure its going to make any difference really given what you have already tried.

To be honest i cant remember what happens when i push the accelerator, im going to have a look tomorrow in the day light and take a pic of the valve too... i'll post it up here tomorrow.
Yes it did start after i fitted the blitz to the car. Strange thing about it, only happens intermittently... was thinking about getting a turbo XS valve as a replacement soon

PhilA

Sounds like the Blitz then. Mine came with the motor, only had this one 3/4 weeks. Here's mine:

CEL

iTrader: (1)

Im more convinced now its the valve... when i first put it on the car and reved the engine it used to open up and dump the pressure... still does when im driving but for some reason its not happening while the car is stationary...

Mines similar to the one you have i think...

PhilA

very similar, just a different trumpet. It should open after you rev high. The adjuster on yours looks all the way in, maybe's it's too far in (if you can adjust them too far). I'll be adjusting mine more over the weekend, will let you know how I get on.

PhilA

Mine's almost gone now I've adjusted it nearly all the way in. If adjusting it doesn't work try the OEM one.

CEL

iTrader: (1)

Mine too seems to be ok at the moment ... think i have a standard one somewhere, i'll give it a try this weekend. Still not sure what could be causing the hesitation while accelerating when its cold though.

PhilA

Stuttering when cold is a different issue. My old MY99 impreza used to do this with the OEM dump valve. Dealers weren't much help as usual. MAF possibly? Not too sure, let me know if you find out.