Boost of 1 bar

[Christophski]

Hmmm ok. So don't put the baileys one on?

[Christophski]

Right so mate jus changed dv over n double checked all jubilees and still not boosting over 1.1. Sometimes only0.8 mark h mod next then will check the flying saucer thing then I'm stumped.

[Jamo]

what condition are your knock sensors in? it could be mechanical and be the turbo has it ever boosted to 1.4?

You are also trying to boost to 1.4 in gears 4,5 & 6?

[Christophski]

I have seen the gauge hit 1.4 in the past. I don't know where the knock sensors are or how to tell if they are ok. Would vag com tell me if they were faulty?

Will have to try some more things when I get back from my holiday in a few weeks time unless there are some things I can do easily visually whilst on holiday with the car. Girlfriend and dog too. Not just me and the car. That would be to obsessive lol!

[prj]

Have you pulled the codes?

[Christophski]

Not yet but I think that's one of the first jobs for my return.

When we did the pressure test we could hear something hissing a bit but couldn't find it

[prj]

6 pages, and you have not pulled codes
Also, the hissing needs to go...

[Christophski]

I know. I need to do both but was trying to get the hissing done first and then need to make sure my mate has a proper version of vag com.

[nesshead6]

Christophski, sjw185, did either of you get to the bottom of the problem?

I've had a similar problem for a while now... at 1st it happened so rarely it didn't bother me too much, but now happens virtually every time i'm out in the car.

The problem is that when I floor the accelerator, the engine gets to a certain revs (or boost?) then cuts out pretty violently. Note that it ONLY happens at full throttle, and after switching engine off and on again problem has gone (for a short while anyway!)

I've tested for boost leaks and found none. Checked vac lines and replaced the one going into the DV as it was split (thought this had cured it as problem went away for a couple of weeks, but came back ). I've tried swapping the N75 valve and have tried 3 different ecu's in the car, standard and chipped.

Recently fitted a boost gauge and find that normally, boost reaches between 1.3-1.4 bar before tailing down to 1 bar (i have a homefried ecu fitted). However when the fault is occurring, boost is limited to 1bar.

Here are the fault codes:





So i'm wondering where to go next? From reading this thread and others perhaps altitude sensor? throttle position sensor as it only happens at WOT (have checked the cable and is definitely fully opening).

Thanks

[prj]

However when the fault is occurring, boost is limited to 1bar.

What have you done to your wastegate?
Own up.
It should be 0.4 bar, and that is the likely cause for your problem.

You have a combination of two things:
1) Boost leak
2) Wastegate that has an overtightened or too stiff spring, whereas homefries are meant for the stock spring.

Fix both problems, and your car will run well again and not cut out.

[prj]

Also, check MAF connector, might be loose or your MAF might be on it's way out.

[Dan]

What have you done to your wastegate?
Own up.

[Christophski]

Unfortuntaely bud I still have a boost leak. I can hear it. A mechanic mate changed my dv and made sure all the hoses are tight and with the leak test kit we can still hear a hiss. Maybe the little brown cube above the dv or even in need of the mark h mod? I have the mark h mod to put on and may try to borrow a brown cube known not to leak to try and see if it fixes mine. Mind you mine does look pretty new and clean even though I have had it 2 years and I didn't fit the thing

[GavS2]

Hi Chris, sorry to hear you still got the boost issue. When you say brown cube do you mean the N75 valve with the three small tubes coming out of it. I changed mine when i had issues and when i removed it to replace it with a new vag one the old one fell apart in my hands, it was very weak. A vag one will cost you £50 and they have got loads in stock. You can buy uprated ones off ebay and other places, i don't know if there better, but they do look stronger in design being that they have a brass t-piece instead of plastic. Anyway may be worth swapping it if its gonna be a matter of elimination and i believe it can be a common problem across the range of turbo S cars.

[Christophski]

That's the jobby if it's located above the dv behind the head light. Maybe that will cure the leak. Gotta be wortha try. Cheers bud