does anybody know about how the boost works in full? i have a hesitation just as the boost comes in to kick the turbo in between 2500 - 3000 rpms then once past that boosts as normal. ive tried cleaning the boost solenoid with carb cleaner today but it still does it, i can hear a clicking noise quite loud in the car when it hesitates not sure if thats the boost gauge needle flicking or something electrical like a bad relay or something... any ideas?

 

also wondering if you have a faulty coilpack would you get the same sort of effect a missfire for example if 1 had a weak spark so wasnt fring as it should...?

 

if it was a week spark it would show up worse when u drive it hard

 

check the tips of the coil packs anyway. look for cracks. they are pretty easy to take out and it wont cost you anything. i had a misfire on boost and it was a coil pack.

 

ok ill check the coilpack tomorrow morning see if i can see any damage... when im driving it is very noticeable, very jerky, but once past 3500 revs the boost is strong and pulls hard and doesnt hesitate again until you let the revs go back down to below 3500 then when you put ya foot down it does it again, i hope it is simple and is the coilpack like yours was : dj219957 as seen them on ebay for about £40 upwards.

 

hhhmm doesnt sound like coil pack when you say it like that. i think you need to have a good check around the engine for loose split pipes, induction leaks, ect. does it have a aftermarket dump valve? they can cause problems

 

yes ive got a blitz dump valve so not cheap crap also blitz sus induction also not cheap and not bad for the maf like k&n, also sti v6 intercooler and a manual boost controller, i noticed the stutter started happening when i got it mot'd i turned the boost down for the emissions test so when i messed around with the boost after it started to hesitate. but if there was a boost leak wouldnt it stutter all through the rev range or get worse with more pressure? it would make sense to be a problem with the boost part of things like boost leak or bad solenoid but what else is there to check, is there any relays for the boost solenoid as i get that clicking noise when it hesitates?

 

so chances are its not the coil pack then...? if it was the coil pack or bad ht lead or plug, wouldnt it mis-fire all the time all the way through the revs? i wont rule it out as had same a similar problem like this last year and got new ht leads and it fixed the problem it also had new ngk laser platinum plugs 5000 miles ago. also the dump valve didnt cause a problem before and its been on the car for 2 years.

 

spoke to fb tuning today and he said it might be lambda sensor or maf,so might be worth trying the lambda sensor

 

Or even spraying the maf with some carb cleaner (carefully)

But then again if it was the maf, there would be a CEL pop up

 

i had the maf code up when i first got the car about 2 years ago, i bought a stainless steel mesh blitz induction kit so the maf wont get contaminated with oil from the paper type like K&N anyway i got some maf cleaner and cleaned the maf sensor wire and never had it come back also havent got that up on the dash at the moment. where is the lamba sensor... is it near the 1st cat the thing you can see near the turbo attached to the exhaust with wire coming out? if so do i need to get a new lamba sensor or do something to it to correct it?

 

Dont always rely on a MAF code coming up. Mine was dead, and didnt throw a code. If i was you, i would check the MAF voltages and the same with the lambda sensor.

 

ok will do, but how do you check the voltage on them? so do you think the hesitation problem could be one of those 2 things?