P2/P80 Visual Audible Tactile Inspection of vacuum hoses VATHI

Post by **abscate** » 23 Dec 2016, 13:29

When we encounter poor running or starting, a common cause is corruption in the vacuum hoses in these cars.

Commonly, these throw codes for oxygen sensor, MAF, misfire, or fuel trim out of range.

You can't just look at your hoses to rule them out, I've found again and again that you need all your senses to make sure you don't have leaks.

I had $1300 of work proposed by BMW to cure P0171 and P0174. It was clear no one was diagnosing, they were just Mossberg Mechanicing....shotgunning a ton of expensive parts.

I knocked off the induction in about one hour..it's a pain on this car

Here's is the intake bellows in installed position

Slight pressure on the idle valve bypass

Post by **sleddriver** » 23 Dec 2016, 13:44

Nice catch! Did they even bother to smoke it? As complicated as modern cars are, a smoke tester is necessary these days for saving time. I should have built mine 10yrs ago.

Post by **abscate** » 23 Dec 2016, 16:10

I built a crude one but decided I would strip it down before I bothered to smoke it. This car, the E83, is known for bad bellows so I knew to really give it the evil eye.

Post by **abscate** » 20 Jul 2017, 07:30

Here are picture details of my smoke tester

Cat litter bucket
CA sage smudge sticks
Clay
pot
Tygon (tm) tubing aka PVC tubing
Brass air fittings
Air compressor - not shown. you just need bit of air flow, you can probably blow to make this work. The side PVC hose blows right onto the smudge to make it glow, then it will puff off thick smoke.

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Post by **MrAl** » 20 Jul 2017, 17:21

Hello Steve,

Nice pics. I have almost that same meter, the 2108 not the 2108A. I have a Mastech bench meter also.
What are you measuring with it though there, i see about 64k Ohms. What is that for?

Is it hard to smoke test the system? Like where do you hook up the smoke injection hose?

A little off topic, but did you ever measure the engine cranking Amps with that meter?

Post by **abscate** » 20 Jul 2017, 18:47

That last picture sneaked in there from a AbS test procedure on the module. I haven't figured out how to test hoses by meter yet

You can tape the Tygon tube nicely to the brake booster, on the suction side of the check valve

Post by **MrAl** » 24 Jul 2017, 16:16

Hi,

Ok thanks, i'll have to locate that next i guess

Post by **abscate** » 24 Jul 2017, 20:06

Big fat hose heading to the brake booster

Post by **MrAl** » 25 Jul 2017, 05:40

Hi,

Thanks, i'll look for that when i go out there again.
I am assuming that smoke does not harm the system?
Does anyone use soapy water for this kind of test?

Post by **abscate** » 25 Jul 2017, 08:02

Most people will keep smoke out of the MAF by pulling off the big snorkel hose and putting a baggie over it. Thats probably smart. Any leak before the MAF doesn't matter , of course.