1995 525i Vacuum Diagram?

[The Deuce]

used

So I've got a 1995 525iT (m50 motor) and it has decided to start hesitating off idle, and sometimes at idle. I've put new plugs in it, checked the MAF (clean) and it's not throwing a code (ck engine, svs eninge all dark) that I can tell. I also changed the plugs for good measure, but no luck.

I'm thinking its a vacuum leak somewhere, and I have at least one idea where the problem is. The intake tube (between MAF and throttle body) is cracking where the auxiallry lines (I'm assuming is block vent and EGR return) come un on the under side.

Beyond that, I'm having trouble locating other vacuum lines and can't find any info in my manual (Bently, I think) where other vacuum lines are. ghead

I'm going to pick up a new fuel filter tomorrow, as well as that intake tube. Hopefully it's not that my fuel pump is on the way out, but that could be a possibility.

[The Deuce]

Any opinions on wether my problem might be related to the following parts?

air bypass valve

idle-air stabilizer

I don't have my manual in front of me to see if either part (or something similar) is even applicable to my model, but I put the intake tube on and it helps a little, but it's not good.

I am still hopeful that there is something I can identify as the issue and get this taken care of without sending it in to the shop. Neither of my other vehicles is quite prepared for the sub-freezing tempatures right now.

I'm still going to swap the fuel filter tonight for good measure. Here's hoping I don't drink too much gas.

[The Deuce]

In what appears to be an ongoing saga, I have yet another hypothesis on this car.

Based on a conversation with a friend who's a better mechanic than I, he suggested that the MAF might be dead, but not tripping the light. I decided to test this theory by unplugging the MAF and running the car.

It runs the same wether the MAF is hooked up or not. It will idle fine, but hesitate when I give it gas, but will hold rpm on slight throttle. The vacuum "Test" showed no leaking when I sprayed the carb cleaner, so I'm going to limp over to Advance in hopes there is a stored code somewhere.

Is there something I'm missing here? Or am I doing what anyone else here would to troubleshoot and that's why I'm seeing views, but no responses?

[billB]

The Deuce

I went through this vacuum leak saga last summer. This is how I did it with a help of a friend on this forum:
looked all over these one by one looking for leaks:
A. Thick ICV hose by the intake.
B. The Crack you mentioned at the boot.
C. Canister to purge valve to intake (hoses).
Everything checked fine except 2 empty cans of carb cleaner at the valve cover. Nothing. OK. The problem was at A. Oil filler cap B. when the whole base of oil dipstick came off the engine with the dipstick in it. Go figure!

[The Deuce]

Thanks billB.

I'm going to pull the plastic cover off the head to see if I can't get a better seal from the oil cap, and I'll check the dipstick tube.