econnelle

I posted in the past about my idle misfire issues and I was told it may be a vacuum issue.

Well I've also had boost issues, moderate acceleration, boost not coming on hard until 3000rpm.

I knew it was a leak somewhere but couldn't not easily find it.

My VAGCOM finally came in and I logged it.

Hit the gas and it spikes to 2100millibars and settles in at ~1800-1900mb.

That seems to be in line with the numbers from the tune that VAST did.

However acceleration is slowerer than stock. No knock, good timing, etc....so the air is not making it to the intake.

Where do they measure boost? Seems odd to measure that much boost and not getting the car to move.

After tuning the car would make good boost at 1900rpm.

It still felt like sometimes it would make good boost, then not make....now all the time its not making it.

So I know its a leak, its not pulling timing or anything like that so based on the condition where would you suspect a leak?

I had it pressure tested and it did fine 2 weeks ago at VAST.

Thanks

Paracaidista2.7T

the throttle body boot. Typical boost leak locations are diverter valves, throttle body boot, and intercooler hoses. Also, check the fit of the MAF housing to airbox and accordion hose. But, you need to pressure test it again.

econnelle

Is my math right?

2100mb is 30lbs of boost?

Something doesn't seem right but I checked it, 2100 x .0145, right?

rageman

Subtract ~1000mb for ambient pressure

Paracaidista2.7T

yep

Edd W

it must be getting to the cylinders. If you had a leak the pressure would never reach that level and your turbo's would fail due to over-spinning.

Could thee be some form of exhaust blockage - cat failure etc or has anything else changed, ie cam belt change etc....?

Raudi_6 akaDeutschMF

I have no tech advice here, still learning all the ins/outs, hope you find the culperate to your lack of boost though!! =) Cheers, Happy Friday