# Loss of power after timing belt replacement



## ddouglas54 (Mar 14, 2008)

I changed the timing belt, tensioner, and water pump on a 2003 Jetta 2.0 L. The timing marks were carefully aligned and checked several times. 
Now, when I accelerate hard (merging on the highway), the engines revs higher than normal and loses power. Once the revs drop below 4K, the power returns normal. At low revs everything seems fine.
Plugs were changed at the same time. The tensioner was adjusted, verified, and torqued. All connectors and hoses that were removed are in-place. 
Any ideas? Did I mess up the mechanical timing even though the marks were aligned?


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## sio (Jan 30, 2007)

*Re: Loss of power after timing belt replacement (ddouglas54)*

i'm going to throw it out there...timing off by 1 tooth?


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## FL 2.0L (Aug 1, 2002)

Manual? Are you describing a slipping clutch possibly?


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## MikeWire (Oct 20, 2003)

*Re: (FL 2.0L)*


_Quote, originally posted by *FL 2.0L* »_Manual? Are you describing a slipping clutch possibly?

x2 - sounds like a slipping clutch. How many miles on the vehicle and have you ever replaced the stock clutch?


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## ddouglas54 (Mar 14, 2008)

*Re: (MikeWire)*

The Jetta has an automatic, so it's not the clutch.
I agree that the timing is probably off by one tooth. I am not looking forward to getting back under the car tomorrow.
BTW: for those interested in plastic water pumps. The engine has 98K miles and the water pump impeller had already lost a few fins.


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## FL 2.0L (Aug 1, 2002)

Maybe the auto is on the way out. That would explain an increase in rpms without the car moving. The engine wouldn't rev if the timing was off. It would bog or miss without the rpms increasing. If you haven't done any maintenance with the auto tranny, 100K for problems is about right.


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## twicepardoned (May 2, 2006)

Changing the timing by a tooth is really easy.
I don't have a timing belt cover so that makes it a bit easier but you can basically do it with bent needle nose pliers and a 13 mm wrench.


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## GTijoejoe (Oct 6, 2001)

*Re: Loss of power after timing belt replacement (sio)*


_Quote, originally posted by *sio* »_i'm going to throw it out there...timing off by 1 tooth?

I'm going to agree....


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## colovw (Aug 27, 2007)

*Re: (twicepardoned)*

Adjusting with pliers and 13 mm? Care to elaborate? Since belt change my 2.0's idle is funky, but 2500 + rpm seems fine. Maybe a tooth off? No CEL though???


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## whitedragon179 (Jan 16, 2008)

*Re: (colovw)*


_Quote, originally posted by *colovw* »_Adjusting with pliers and 13 mm? Care to elaborate? Since belt change my 2.0's idle is funky, but 2500 + rpm seems fine. Maybe a tooth off? No CEL though???

Had same issue with mine. Get the timing correct and you will see a big difference. Not so sure about the needle nose pliers. I was able to get me timing on and off with just my fingers. Warning. before you move anything mark where it is at now. The top cam may be half way through a valve movement and that sucker will jump on you. Best bet is to just do the timing your with lining the top cam gear with the OT on cam and case then the bottom pully can be moved with a 18mm socket till the notch on the pulley is lined up with an indented arrow on the plastic timing cover then line the intermediatear up by looking under the distributor cap for the first cylinder mark. Once you got all that put the belt on careful not to move anything and it whould take honestly no more than an hour tops with tools and basic knowledge of lines and marks. Need any help lining stuff up or finding things let me know and I can get you pictures. http://****************.com/smile/emthup.gif http://****************.com/smile/emthup.gif


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## mittimj (Dec 27, 2006)

theory. Old belt was old and streched out. Tensoiner was cranked up causing cam to be turned a little counter clockwise. 
The new belt is correct length, tensoiner is looser and cam is more clockwise.
But anyways, I also think your off a tooth on the belt.


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## colovw (Aug 27, 2007)

*Re: (mittimj)*

Thanks for the replies guys. Check out this mess:
Well...
Spent about 5 hours the other night messing with timing. I probably re-timed the thing 25 times (seriously) using the TDC and other marks.
Here's what happened:
CEL popped with a 300,301,302, 341. The 300,1,2 are random misfires and misfires on cyl 1 and 2. The 341 is cam sensor. 
So I figure the cam is off a tooth and causing misfires. Makes sense right?
I go in to the 25 or so off and on with the belt. 1 tooth this way, 1 that way. 2 this way, 2 that way. Straight up over and over. All with the same results - popping the same group of codes only without the 341. WTF? 
I pull the valve cover just to verify #1 is in the right spot. Yep.
Put it all back together. While running, I start pulling plug wires. When I pull # 2 the idle doesn't change. Spend another hour pulling plugs, checking for spark. Seems like it's all there. At this point it's about 11:30 and I can't take any more.
Yesterday I stop in a NAPA and pick up new cap,rotor, plugs, wires. Put them on. Guess what? I could have save myself 5 hours of frustration by doing this at the beginning.
Seems I messed up a couple of wires when I had the cap off to check rotor position.
At least I have timing belt changes down to about 15 minutes










_Modified by colovw at 11:35 AM 3-21-2008_


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## Jay-Bee (Sep 22, 2007)

*Re: (colovw)*


_Quote, originally posted by *colovw* »_Yesterday I stop in a NAPA and pick up new cap,rotor, plugs, wires.

Cap, Rotor.. what??
Does your car not use a coilpack? my AEG does.


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## MikeWire (Oct 20, 2003)

*Re: (Jay-Bee)*

He's not the OP. And he has a MKIII.


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## colovw (Aug 27, 2007)

*Re: (MikeWire)*

I hijacked dd's thread. Sorry dude.
Yeah it's a Mrk III 8v.
ddouglas - any updates?


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## gtdubber (Dec 3, 2004)

*Re: (Jay-Bee)*

Jay,
The MkIII's don't have coil packs. The AEG is a MkIV engine. 
ddouglas,
Honestly, check all your timing marks (crank, cam, intermitant shaft isn't too important as long as the rotor/distributor lines up at TDC). That's probably where your problem is.


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