P0103 Adventures

[Oh Randi]

I'm pretty much doing this thread as a documentary in hopes it will help someone out somewhere along the line.

So I'm getting the P0103 code, or according to ross tech wiki:
16487/P0103/000259 - Mass Air Flow (MAF) (G70): Signal too High
Possible Symptoms
Probably no serious malfunctions
Loss of power
Possible Causes
Wiring and/or connections (short circuit?)
Mass Air Flow (MAF) (G70) defective
Possible Solutions
Check wiring and connections
Check / Replace Mass Air Flow (MAF) (G70)
Special Notes
In MY 1995-2002 (?) in Europe at VW-diesel-cars G70 had the bad reputation of slowly losing his performance, causing loss of power. It's not a matter of defective or breaking down, but it is filthy / dirty (not easy to clean). You can check functionality by making a log in [01-engine], [meas.blocks-08], group 003 (3e gear, full throttle, from 1700-4000rpm)


In MY case, I don't believe the MAF is the culprit. I think I have a boost leak. While merging on the highway one yesterday, I heard a distinct, kind of deep sucking noise. My intake is loud, but it sounded wrong. I thought the intercooler hose popped off at first, but then realized it only happened under full boost. Perhaps there is a slit in a hose somewhere making it only apparent at full boost? Going to get it checked out today as I can't see anything obviously wrong with it. I'll keep y'all posted.

[Smileybug]

What makes you think its not the MAF? Just curious really.

[Oh Randi]

I don't have any problems with the idle or hesitation or stalling. I'm not throwing any lean or rich codes. I just knew by the way it was driving it was a boost leak.

Took it to a local shop I'm friends with, got it up on the lift and after 30 minutes of searching, we found what may be the issue, something not tightly clamped on. I'm still at the shop as I'm writing this, so ill update in a bit to confirm this was the issue. If it isn't, a leakdown test is in order.

On the sucky side, found out my turbo is leaking oil and coolant. not bad, something I just need to keep an eye on and prepare to replace it in the next year or so.

[IndyTom]

Sounds like the Diverter Valve to me.


Do you have a Boost Gauge? If so what are your Boost readings at Full Boost?

[Oh Randi]

My diverter valve is the forge 007, properly oiled and maintained. No rubber diaphragm to rip like the OEM one. It sounded like it was operating properly, and with my short ram intake believe me you can hear it. The leak sounded WAY different than a blown DV (which sounds like a honking noise, ask me how I know lol).

I do not have a boost gauge, however I do have my VCDS software which I used for some quick data logging. Boost was within spec until it got close to 7 or 8 psi ( pretty close to full boost for stock) which is when I heard the noise. So we started poking around under the car for leaks and BAM, there it was. The clamp on the elbow right off the turbo that connects to the turbo outlet pipe was just chillin there, not clamping anything. I think it was on vacation

Tightened the clamp and took it for a drive. All was well.

I am not mechanically inclined whatsoever. I learn new things about this car every day. My testing procedures aren't the best, in aware, but I really had a gut feeling about it being a boost leak, not the MAF. I just thought I'd post my experience here for others to learn from, And maybe prevent someone from wasting money on a new MAF, and deciding to sell the car when it doesn't fix it.

[IndyTom]

Originally Posted by Oh Randi

My diverter valve is the forge 007, properly oiled and maintained. No rubber diaphragm to rip like the OEM one. It sounded like it was operating properly, and with my short ram intake believe me you can hear it. The leak sounded WAY different than a blown DV (which sounds like a honking noise, ask me how I know lol).

I do not have a boost gauge, however I do have my VCDS software which I used for some quick data logging. Boost was within spec until it got close to 7 or 8 psi ( pretty close to full boost for stock) which is when I heard the noise. So we started poking around under the car for leaks and BAM, there it was. The clamp on the elbow right off the turbo that connects to the turbo outlet pipe was just chillin there, not clamping anything. I think it was on vacation

Tightened the clamp and took it for a drive. All was well.

I am not mechanically inclined whatsoever. I learn new things about this car every day. My testing procedures aren't the best, in aware, but I really had a gut feeling about it being a boost leak, not the MAF. I just thought I'd post my experience here for others to learn from, And maybe prevent someone from wasting money on a new MAF, and deciding to sell the car when it doesn't fix it.

I am 100% with you Randi! Too many times the MAF gets blamed for things it really doesn't have anything to do with. I don't know how many times people are replacing perfectly good MAF's in hopes it will magically fix all their problems just to find out it wasn't the MAF at all. Good call on the boost leak!
I once had the same issue on my Audi TT. Back then I didn't know better and took it to the dealer. They couldn't figure it out for over 5 days, then finally replaced that little elbow hose comming of the Turbo and charged me 800 bucks for it. From that point on I never took it back there again and made it a point to learn more about these cars.

Have a fabulous day!

[Boost Master D]

This posting was helpful,..thank you kindly. This also inspired me to become more knowledgeable in my lil turbo buddy.

cheers.

[IndyTom]

Originally Posted by Boost Master D

This posting was helpful,..thank you kindly. This also inspired me to become more knowledgeable in my lil turbo buddy.

cheers.

You got your work cut out for ya! Good Luck!

[Oh Randi]

Originally Posted by Boost Master D

This posting was helpful,..thank you kindly. This also inspired me to become more knowledgeable in my lil turbo buddy.

cheers.

You're very welcome!


IMO, we don't have enough threads on here where people actually follow up on the solution. So, everything I encounter that may help someone else out, I will come back and post about. I like having a discussion with people throwing out options, and eventually stating the solution. It's very helpful for people that just like to lurk and get ideas to help them troubleshoot.