surging at low rpm

[gts1969]

I have a 2002 1.9L TDI Beetle that is surging at around 2000 rpm while driving. Actually seems to do it at any rpm if you hold steady. I have been running diesel additive lately and just replaced fuel filter-it was doing this before changind filter. You can see it serge about 200 rpms on tach. If anyone can help with this, any suggestions appreciated, please chime in. Thanks

[MichelleRoze]

I'm not sure what would cause the surging....have you cleaned the turbo and intake yet? I know additives will HELP with that, but if they were clogged or really dirty, it's not going to clean them completely. How many miles? Auto or manual?

[DZLBUG]

Originally Posted by MichelleRoze

Auto or manual?

Ditto. If an automatic, it sounds like the TCC in the valve body is failing.

See "Test Case 2" in this thread:
01M part 3 - TDIClub Forums

[gts1969]

Yeah it is an automatic and has 113000 miles on it. Never changed transmission fluid. Always was told by buddies in transmission field that don't mess with what ain't broke. Anyway if it is the TCC how complicated is this to fix and also is there a detent adjustment. I thought this may have something to do with it also...

[DZLBUG]

No adjustments to be made. I would suggest reading up on that thread I linked you to and other similar threads like it. Talk to the guy who wrote it, he is an excellent resource.

Best thing to do would be to drop the pan and remove the valve body to have it rebuilt/replaced. Its not that hard to do, but you have to be extremely careful with the ribbon cable and its clips. Richard (CoolAirVW) can either rebuild your valve body or send you one if he has one ready to go to exchange.

If you let it go much longer you are guaranteed a premature failure. Fixing the valve body doesn't guarantee you will have a long life out of it but its your best chance if you want to keep that trans going and to eliminate further damage. Simply put, they are a very poor transmission that (other than the valve body) are extremely expensive and difficult to repair. Rebuilds of these transmissions do not work. Many don't last beyond 150k miles. Some don't even make it to 100k miles.

If you want to keep the car long term, strongly consider a 5 speed swap. Relatively cheap and cost-effective, and the powertrain will easily outlast the body if properly cared for. Both Michelle and I have done it and are extremely happy.

[RackaRacka]

Originally Posted by DZLBUG

No adjustments to be made. I would suggest reading up on that thread I linked you to and other similar threads like it. Talk to the guy who wrote it, he is an excellent resource.

Best thing to do would be to drop the pan and remove the valve body to have it rebuilt/replaced. Its not that hard to do, but you have to be extremely careful with the ribbon cable and its clips. Richard (CoolAirVW) can either rebuild your valve body or send you one if he has one ready to go to exchange.

If you let it go much longer you are guaranteed a premature failure. Fixing the valve body doesn't guarantee you will have a long life out of it but its your best chance if you want to keep that trans going and to eliminate further damage. Simply put, they are a very poor transmission that (other than the valve body) are extremely expensive and difficult to repair. Rebuilds of these transmissions do not work. Many don't last beyond 150k miles. Some don't even make it to 100k miles.

If you want to keep the car long term, strongly consider a 5 speed swap. Relatively cheap and cost-effective, and the powertrain will easily outlast the body if properly cared for. Both Michelle and I have done it and are extremely happy.

+1 What he said, very good advice

[VdubOne]

You probably shouldn't use diesel additive depending on where you live, some localities have additive in their diesel fuel, be careful what you add

[DZLBUG]

Originally Posted by VdubOne

You probably shouldn't use diesel additive depending on where you live, some localities have additive in their diesel fuel, be careful what you add

I always run additive in my TDI, there is nothing wrong with it. Some diesel is better than others as far as additives, but I always like extra insurance with lubricity and (during the winter months) anti-gel. Power Service in the white bottle during the winter, Power Service in the silver bottle the rest of the year. Lubricity additives are mandatory as far as I am concerned, particularly on the rotary pump TDI's now that ULSD is fully in effect. It is a fairly "dry" fuel, especially straight D2. In states where at least 2% biodiesel is mandated, its not so bad.