Vw passat tdi 130 temporary limp mode

markoire

Hi folks, was coming home from work a while ago and all of a sudden my passat went into what appeared to be limp mode.. It was as if there was no turbo or something!! There was no bang, no smoke or anything and after I pulled over, turned it off and restarted it the problem was gone!! Any ideas what it might be or has it happened to anyone else?! Im thinking it has something to do with a vac hose or some sort of pressure sensor!!
Thanks, Mark.

TheBigGreen

My Focus went into 'limp mode' on the way home after work today. Not enough fuel getting into the system, probably new injectors or new fuel pump I was told. Will know more tomorrow. Get it looked at ASAP.

bazz26

Could be anything really, did any warning lights appear on the dash? You would really need the car hooked up to a diagnostic computer to see what fault codes if any were logged on the car's ECU.

markoire

Hey Bazz, no warning lights or anything!! Very strange, thought the turbo had gone intiially. Going to get it plugged in to find out what the problem is!

YbFocus

Chances are its the Air Flow meter man, cuts out randomly and onc you restart it's OK for a while.
This if it went wrong wouldn't bring on a light or anything.
I'll put a few pound on it being that

George Dalton

YbFocus wrote: »

Chances are its the Air Flow meter man, cuts out randomly and onc you restart it's OK for a while.
This if it went wrong wouldn't bring on a light or anything.
I'll put a few pound on it being that

I am curious about this because I see it all the time on internet forums and it doesn't correlate to my own experience.

At a very conservative guess I'd say I have fixed well over 100 VAG TDIs with limp mode problems. The causes have ranged from simple to complex to the downright bizzare. One thing that I have never seen is a MAF causing limp mode.

YbFocus

Anytime I've had this problem with my own vw's at the time or friends cars of the vag group, almost always have been settled by this fix.
It happened to me twice personally, driving along and car looses power and will not come back until you restart it, once you do its back to normal
Both times solved by a new AFM, worked with friends VAG cars too.

I pray I never get any of these horrible limp problems, thank god it's only been a €40 fix

George Dalton

What fault codes were being logged when you had these problems?

In my experience limp mode will result in one of two fault codes, in layman's terms either the ECU is seeing underboost or overboost from the turbo:

http://wiki.ross-tech.com/wiki/index.php/16683/P0299/000665

http://wiki.ross-tech.com/wiki/index.php/16618/P0234/000564

A bad MAF won't cause either of those codes.

YbFocus

Don't know the codes george, was pointed out originally by a mechanic friend of mine and it has always fixed it since then. Don't have diagnostics myself.