P1556 Limp Mode Diagnosis Problems

[puter]

I dunno what either is composed of.

If you etch that element you will change its mass, which will lower the airspeed necessary to cool it. This will make it look like you have more airflow than you do.

it may have helped because it got the crud off but caused other problems with the maf.

I'm just saying that pick up some maf cleaner next time. It's cheap, one bottle lasts forever. Right tool for the job

 

[WVU TDI]

Seeing all this about checking the MAF... I've been having limp issues for quite a while now, replaced all of my vac lines and checked the connectors, etc, so I should be good there. Tried checking my N75, but I'm not sure that I was doing it right.

If my MAF should ok on vagcom, at or well over the requested MAF amount, it should be fine, right? Or could it still be bad but show good on vagcom? Hope that makes sense.

edit: This is on the '01 Golf, btw.

 

[puter]

try running without the maf and see if you still go into limp mode.

 

[WVU TDI]

That's what I was wondering, vagcom showed it was good, but I guess it could still be bad. I'll try it out this weekend

 

[nathan100]

I am going to chime in for a fact check here as I think my MAF is showing signs of going bad. The car had a K/N Air Filter for about 60,000 of its 125,000 mile life. I changed back to a paper filter at 113,000 after reading about how the K/N was not good for my TDI. (Correct?) After going back to paper filter the car went into limp mode a few times. In the few (3) cases it was in limp mode I restarted and it reset to normal. A check engine light came on when I did a long trip to AZ, but it cleared itself and I haven't had any problems since. I have taken extra care to shift a little higher to keep the turbo vanes clean. CA car since new.

Could a bad MAF, or one that is going bad cause this? Also, my brother has a tdi also, he had his MAF replaced, and his car is way faster (3-4 car lengths up to 60-70) (both are 5 speeds). Again could a MAF be the culprit?

Thanks!
Nathan

 

[BobnOH]

lazy man's diagnoses: swap MAFs with your brother

 

[nathan100]

Haha.. Not a bad idea! He moved out of state though. Anyone else want to swap? J/K

 

[BobnOH]

there is loads of info on diagnosing your problem. Be careful though, there is a fair amount of misinformation as well.
BTW oiled air filters do seem to damage the MAF sensor

 

[VOLKSWAGEN_JETTA_TDI]

I'm developing a problem where its fine on the street but when i get on the road, and need rapid acceleration, the car revs all the way up to 4500 and then shifts to 3rd or 4Th gear. This didn't happen before and it doesn't look like the tranny, and on the highway after 110km, the car is really to accelerate to a higher speed. Anyone the problem? MAF sensor?

 

[puter]

I'm developing a problem where its fine on the street but when i get on the road, and need rapid acceleration, the car revs all the way up to 4500 and then shifts to 3rd or 4Th gear. This didn't happen before and it doesn't look like the tranny, and on the highway after 110km, the car is really to accelerate to a higher speed. Anyone the problem? MAF sensor?

Don't double post. You already have your own thread going and you have a response to it.

I suggest deleting one of the posts.

 

[ARMOURPASSAT]

With the CEL on will I still be able to tell if the MAF is bad by unplugging it? It is an 04 Jetta.

Thanks,
Dan.

 

[ARMOURPASSAT]

Does anyone have an answer to my question???

Thanks,
Dan.

 

[Canadian_Grizzly]

Dan quick answer is maybe. Unplug the Maf and if there is no difference or it runs better that is a pretty good indication Maf is bad.

 

[ARMOURPASSAT]

Thanks Byron!!!

 

[bobbyo]

i've had a few 252 codes (injector pump fuel metering control) and 1 234 code (turbo over boost).disconnected maf and went instantly into limp mode.reconnected,went up a hill-limp mode.does this mean maf,vacuum hoses or,perhaps the turbo unit itself?as i'm not very mechanically inclines,i'm trying to narrow the options for my mech.thanks.'03 jetta tdi 240k

 

[12valveauto]

[2003 beetle 5speed]i have the p0234 over boost code i tryed the maf thing it dosent seem to go into limp mode but there isent a big power increase. but seems to be a little better. but not as big of increase as turning the key off to reset. would this still be a maf problem?

 

[tscott1224]

Didn't think it was worth starting a new thread for this one because it is related... I was driving to work this morning and I lost all boost going up hill. Used the Scangague and it gave me p1556. I restarted the car, felt like it had a little more power, then it cut out again. So I unhooked the Mass airflow sensor and drove it home. I didn't get a code for the limp mode again, it seemed a little under powered, but better than no boost at all. I was seeing boost values on the scan gauge of 12+, but wasn't paying too much attention, could have been higher. It wouldn't go over like 3 when it was in limp mode.

Now a little side note. Every once in a while when it was cold or damp out, like today, its poring and wet. I would sometimes have this issue, but it would go away after driving like a mile. But I haven't had that issue for the past few months.

For now, when I get home tonight I clean it off and plug it in and see if it runs correctly. I have some of the mass airflow sensor cleaner. My question is, does this sound like just a MAF sensor issue?

Also the other day I felt a little power loss when i was pulling on to a highway, but it came back and didn't reappear.

 

[dirty_530]

Sounds like a classic maf problem to me.

Try running with the maf unplugged and see if the problem goes away, if it does then clean the connections on the maf with some deoxit and unplug/plug it back in a few times. If this fixes it then your connection was dirty, if not then replace the maf.

I was having the same problem on my 2001 jetta, I unplugged the MAF and I no longer have the problem. My question is, if I leave it unplugged for a week and still commute in my car while the new MAF is being shipped will I be doing any damage?

 

[BobnOH]

I was having the same problem on my 2001 jetta, I unplugged the MAF and I no longer have the problem. My question is, if I leave it unplugged for a week and still commute in my car while the new MAF is being shipped will I be doing any damage?

unlikely

 

[dirty_530]

Perfect is there anything I should keep an eye out for?

 

[BobnOH]

pedestrians, road debris, large rocks.
We know something is screwey with the engine controls, but with no signal from the MAF, should tell it to run safe.

 

[dirty_530]

pedestrians, road debris, large rocks.
We know something is screwey with the engine controls, but with no signal from the MAF, should tell it to run safe.

hahaha I see what you did there, right on sounds good man. Thanks again

 

[tdilive]

MAF part OEM or not?

I have found a wide range of prices for the MAF sensor... $59 - $150 and all different brands. Does it make a difference which MAF sensor brand that is purchased?

 

[BobnOH]

yes, get a Bosch.

 

[Dave_D]

I have been happy with a Pierberg originally used on a MB here since my original one failed.

Dave