Bigpower

Advice please chaps!
Old yella is being a pain in the butt at the mo. If i use only the top part of the throttle its fine, But bury the peddal in say second gear and it pulls back hard then backfires (big time!) I know coilpacks are the first thing that springs to mind, But ive changed them....Twice.
The time line goes like this....
Remapped may 2011, Maffless esl live map by duncan on garys rollers with Td05 turbo and 550cc injectors fitted Along with fuel pressure reg.
Ran well at cadwell until i thought i had blown the turbo at the end of the day. I then had Tim (ex zen) fit another turbo and it turned out the actuator had stuck open. On road test later we noticed a slight pulling back on hard exceleration. The first thing that sprang to mind was coil pack! The coil packs i have fitted were brand new in 2009 so had covered no more than 3k miles..
I then changed the plugs just incase gapped to .7 with more (this time second hand) coil packs. This made no difference but the car was still driveable because the pulling back faded away after about 20 mins of driving from cold. It then did the marham weekend and ran fine...
It was used very little last year and saw no track action, But in the few times i did use it i noticed that the pulling back followed by the backfire was getting worse and not clearing. By the time the charity race came at snetterton last november it was horrible! Anything more than half throttle in first second or third would cause said effects only in fourth or fifth at 60+mph can full throttle be used. Oh and i had forgotten the shocking high fuel consumption. The 90 mile round trip to snetterton it used north of

Worth cleaning out the boost solenoid with carb cleaner
I had similar symptoms and they improved after cleaning out the solenoid
But was still not right
I ended up changing the whole unit from one that was being broken local to me and has been perfect

Thanks Trev, I will give that a try!:coolgleamA:

This is just a thought and could be completely wrong but if the turbo had slight problems when it was mapped and then you replaced the turbo with a fully working one could the map be out causing it to run badly?

Blimey i hadn`t thought of that one...
the boost solenoid seems like easiest one to look at first though.
Thanks for the reply Fezza.

Well im not ruleing out the boost soleniod but cleaning it out with lashings of brake cleaner has made no difference what so ever.
I did expect to see lots of crap being washed out but i didn`t realy see anything come out that looked dirty. i even cheched the pipe to the turbo and that seems clean and free from blockages.

Throttle position sensor?, crank angle sensor?, my gtr was the same when the cas went

Whats the boost pressure look like when its messing about?
High/Low/Normal?

When I cleaned mine out it ran clear aswell, I was expecting to see loads of crap
It did only slightly improve it though
Did you join the wires under the dash so the solenoid clicked ?

Mine was fixed after replacing the whole thing it's attached to which includes map sensor and the sparky thing for the coilpacks

maff wrote:Whats the boost pressure look like when its messing about?
High/Low/Normal?

Err umm...my boost gauge can`t be trusted. That is another story though and is on my very long list of things to do after ive got it running right.

Ben wrote:Throttle position sensor?, crank angle sensor?, my gtr was the same when the cas went

Throttle position sensor? I thought that only applied to fly-by-wire systems? I would have been looking at the mass airflow meter as ive come across many vauxhalls that have produced simular symtoms when thats been fooked, But is mapped so its no longer needed.

Tk wrote:When I cleaned mine out it ran clear aswell, I was expecting to see loads of crap
It did only slightly improve it though
Did you join the wires under the dash so the solenoid clicked ?

Mine was fixed after replacing the whole thing it's attached to which includes map sensor and the sparky thing for the coilpacks

Join the wires under the dash? Please tell me more...
I think i will go and see the boys at impreza breakers and get a whole replacement unit although i did get the later 97spec map sensor when it was mapped.
Failing that i will have to get intouch with Tim and see what he can do.

Thanks again guys for the input.