P0102 hot film MAF error code + Tank vent leak

[siddharth]

Hi guys,

I got a CEL with P0102

" P0102 : Porsche fault code 115 - Hot film MAF sensor "

... should I just replace the MAF? I replaced the last one about 20k miles back.

Also I got a

"P0442: Porsche fault code 97 - Tank vent system ". I kinda get this each time I fill gas, so I think it's a gas cap issue. What the fix to the gas cap?

The car is a '99 996, C2.

Cheers!

Sid

[Loren]

P0102 Mass Air Flow Sensor - Below Lower Limit

possible causes:

- Open circuit

- Short circuit to ground

P0442 Fuel Tank Ventilation System {Micro-leak} - Below lower limit

possible causes:

- One or more leaks in fuel tank ventilation system

Looks like separate problems...

P0102

Make sure the MAF sensor is plugged in. I've seen techs accidentally forget to plug it back in after replacing the air filter.

P0442

Look for leaks in the vent lines, shut off valve, and EVAP canister purge valve.

[PTEC]

As for your P0442, one easy thing to check would be the O ring on the cap, if its cracked it could be your problem. I think a new cap is like 15 bucks.

Edited February 24, 2010 by PTEC

[siddharth]

P0102 Mass Air Flow Sensor - Below Lower Limit

possible causes:

- Open circuit

- Short circuit to ground

Looks like separate problems...

P0102

Make sure the MAF sensor is plugged in. I've seen techs accidentally forget to plug it back in after replacing the air filter.

Thanks Loren. I've verified that it's plugged in. I also looked for fused but I didn't find any blown fuses (in fact there is no fuse for the MAF!!)

Between which two pins of the socket (or the MAF itself) should I look for open ckt or short? I can borrow a multimeter ...

P0442 Fuel Tank Ventilation System {Micro-leak} - Below lower limit

possible causes:

- One or more leaks in fuel tank ventilation system

P0442

Look for leaks in the vent lines, shut off valve, and EVAP canister purge valve.

Thanks, this sounds a little involved ... if you have tips, I'm all ears ... otherwise on pelican's website looking at the diagram :) !!

And I'll check the fuel cap too!

[siddharth]

P0102 Mass Air Flow Sensor - Below Lower Limit

possible causes:

- Open circuit

- Short circuit to ground

Looks like separate problems...

P0102

Make sure the MAF sensor is plugged in. I've seen techs accidentally forget to plug it back in after replacing the air filter.

Thanks Loren. I've verified that it's plugged in. I also looked for fused but I didn't find any blown fuses (in fact there is no fuse for the MAF!!)

Between which two pins of the socket (or the MAF itself) should I look for open ckt or short? I can borrow a multimeter ...

After much hunting I found the diagram for the MAF. It's

so do you know between which two terminals the open circuit/ short circuit might exist? I presume I have to verify this (short/open) on both the wiring plug as well as the MAF sensor socket?

[DTW_JWA]

I'm thinking that its not a MAF failure. Do you have three warning lamps on in the dash? Did you replace or disconnect your battery lately?

[siddharth]

So I replaced the MAF and the fuel cap. The P0102 hot film MAF error code went away but the Tank Vent Leak code (P0442) came back in a couple of days. Does anyone know where in the technical manual I can find some more information on the piping? I can try to follow that piping/system to see the source of this error ...

Thanks!

Sid

Edited April 11, 2010 by siddharth

[Loren]

1 - EVAP canister purge valve

2 - EVAP canister

3 - Purge air

4 - Tank

5 - Pressure sensor

6 - Shutoff valve

7 - Operating purge valve

8 - To intake manifold

9 -Vacuum control valve

I sent you some troubleshooting...

[cliftony]

1 - EVAP canister purge valve

2 - EVAP canister

3 - Purge air

4 - Tank

5 - Pressure sensor

6 - Shutoff valve

7 - Operating purge valve

8 - To intake manifold

9 -Vacuum control valve

I sent you some troubleshooting...

Can you send me also the troubleshooting guide? Thanks!!