Neilg7777

iTrader: (9)

After my stalling problems i have changed my spark plugs and filter. This has stoped it stalling but when driving the car in 4th gear and at 2000revs the car pulls and releases so like a rocking movement. The turbo gauge goes up and down not a lot but about half of centemeter. The idle can also drop right down but not always. It does it in other gears but more noticable in 4th, it is not violent. Also can some one post a pic of a idle valve think i found mine but not what i expected so did not clean.

This is one of the spark plugs i took out does it tell any storys.



Many Thanks Neil

joey_turbo

iTrader: (26)

Do you have an aftermarket dump valve?
If you post a picture of your engine, I could probably spot the ICV, it should be around near the throttle body.

mylittlepiglet81

bttt

prana

is your A/C on during the hopping ? Do you mean when changing gears or when lifting on and off at light throttle and low revs ?

If you ask for too much boost from very low throttle, the control system over-compensates causing it to oscillate slightly and tends to happen more when the compressor is on. I'm not sure if this is the symptom you are describing but this happens in many Turbo Imprezas I've been in. I remove that my dropping the target boost at low throttle below 12% throttle, so it doesnt overcompensate from vacuum to my target. Nicer to drive too but doesnt 'feel' as strong coming onto boost.

Neilg7777

iTrader: (9)

The a/c is not on and it is when i am going steady at around 2000 revs constant. Found it a bit worse last night.

Pics of my DV



Am i right in thinking the ICV is at the top right



Thanks Neil

scooby_matt

Shouldn't there be a bung in the end of the blue pipe underneath the DV?

Neilg7777

iTrader: (9)

when i asked the question what is that blue pipe i was told i should not block it can not remember what they said it was for. If i wanted to remove the DV what would i need to do
Thanks Neil

scooby_matt

The blue pipe is where the re-circ valve feeds air back into the system. I'm 99% sure it should be blocked when using a VTA DV.

360ste

iTrader: (1)

BLOCK IT NOW. your engine is pulling lots of unfiltered air into the engine bypassing the MAF sensor. So you are probably running dangerously lean which mixed with a grit bath is not good for your engine. Who ever told you to leave that pipe open needs informing of there incompetence.

Neilg7777

iTrader: (9)

I will try to find the post but i am sure they said it was re-circ valve and to leave well alone will post thread when i find. have not driven car today and will not until it is blocked. What is a VTA DUMP VALVE Should i take it off
Thanks Neil

scooby_matt

A Vent To Atmosphere DV is what you have and does as it says, releases the boost pressure into the air when you close the throttle.
The standard recirculating valve puts the air back into the engine via the blue pipe.
You definately need it blocking with setup you have at present.

Neilg7777

iTrader: (9)

Its a baileys of some sort, The thick blue pipe is probably being used to block of the o/e re-circ pipe so leave well alone,And yes its fine to Tee into the smaller one for a boost gauge.

This is what was said so it sounds like the same thing ?

scooby_matt

The thick blue pipe is the o/e re-circ pipe and does need to be blocked with the type of dumpvalve you have.
My advice would be to go back to the standard re-circ valve as there are many reported problems with aftermarket VTA dumpvalves such as the one you have.
Your call

Neilg7777

iTrader: (9)

Not to bothered about the DV it was on when i bought it scared the crap out of me when it first went off on test drive. What would i need to do and buy to put it back to normal
Thanks guys for your help again may have saved me lots of money.
Neil

scooby_matt

What year is the car?

Neilg7777

iTrader: (9)

Its a 1996 v3 sti wrx Ra
Thanks Neil

scooby_matt

Is the blue pipe just a few inches long and attached to a metal tube, or is it about a foot long and run towards the turbo?

Neilg7777

iTrader: (9)

Its about 2inch and runs to the bottom not the turbo
Thanks Neil

scooby_matt

Right, it sounds like the blue tube is a kind of adapter to allow the bung to be put in place (there would have been a bung supplied with the DV).

If you decide to keep the VTA DV, you just need something to bung the end of the blue tube (make sure it's big enough not to get sucked into the tube).
If you want to change back to the standard re-circ valve, you'll need the re-circ valve and the large diameter pipe, which will go between the re-circ valve and the tube that the blue pipe you have at present is attached to.
Someone on here will probably have one for sale for next to nothing.

Neilg7777

iTrader: (9)

Do you thinking changing back would be the best bet as i no the DV can cause more problems or do they actualy do some thing then make a noise.
Thanks Neil

scooby_matt

They don't do anything apart from produce the noise, and that's all personal preference.
If you want to keep the noise, try blocking the pipe off and see if this reduces the running problems you're having. if you're still having problems, the DV could be the cause and you may be better changing to the OE part

Neilg7777

iTrader: (9)

I will block the hole for now to see if that improves the problem and then will change it. Thank you very much for your help

Neil

scooby_matt

Hope it sorts it mate

Neilg7777

iTrader: (9)

Looked at it this morning and it has a plug in it so i dont think that is the problem any other ideas

Thanks Neil

Neilg7777

iTrader: (9)

Could it be the coil packs, how hard are these to change
Thanks Neil

Neilg7777

iTrader: (9)

Anybody