HI All,

I decided to check my engine vacuum tonight (2001, A4 1.8T, Q, tip). I plumbed in a "t" in the fuel pressure regulator line. The reading is just under 16 inHg (A/C off). I thought this was a bit low. Does anyone know what would be considered normal?

Thanks

 

That's a tad low, but not much. I see about 18-20 at idle, 22+ decelerating in gear. What kinda shape are your vac lines in? Done a boost leak test? Was the engine at operating temp when you checked it? If it's a cold start and the idle is still high the vacuum will read a little bit lower.

 

Thank you for responding. I've replaced every vac line I can see or find with silicon. It was a warm start (normal idle). I did a boost leak test recently in an effort to find a major leak, but there could still be a leak. I used the tennis ball method and the leak I had (the "L" shaped pipe that runs to the so-called vacuum pump/booster/plastic thingy had torn).

To be honest, I am looking for a vacuum leak in a rather sideways effort to determine if the fuel pressure regulator is behaving properly on acceleration.

If you are aware of any good ways to look for vacuum leaks I would love to hear them.

Thanks

 

You pretty much covered everything I was going to tell you to check. The easiest way to find boost/vac leaks is with a smoke machine, but they're expensive. I saw a youtube vid of a guy who used a cigar instead but I'm pretty sure I would have a heart attack if I tried to puff a cigar fast enough to create that much smoke.

 

*****

 

LOL suck it!

 

God that sounds ghey chrissy

 

Too much puffing and sucking in this thread for me

 

Well it is me, afterall