99 Jetta -engine issue

[SuperVWNut]

Hi, drove my daughters 99 Jetta to Missoula from Seattle without a problem but once here, the engine started missing badly. I think it is a 2 liter, non-turbo model.The car starts and runs OK but knocks badly, rough idle and there is no acceleration. I have to keep the revs up pretty high until I get to about 45 - 50 MPH. It tops out on the highway at 65 & takes longer to get there than my 79 bus! It is using more fuel than usual and I smell a 'hot rubber' odor when I stop, No check engine light but something is clearly wrong. I thought it might be a fuel issue so I added seafoam to the gas tank but my son(dubber) says it is an ignition issue. The timing belt was just changed in Seattle by my son in law so I was wondering if it could have slipped or something. It goes to the dealer for diagnostics tomorrow but I was wondering if anyone had any ideas?

[Checkers]

He might have moved the cam or something when he was putting the new timing belt on. That's what it sounds like to me!

[kompressorgolf]

I bet it jumped timing

[Mikewire]

I won't discount the belt jumping a tooth, but that's pretty rare. If the tensioner were loose enough to skip one tooth, it would more likely skip more than one tooth and you would have a bigger issue. The 2.0L is an interference motor, meaning that the pistons would contact the valves and you would have a big problem and a car with a paperweight for a motor.

From your description I would lean more towards it being an ignition problem. But it would be best if you can get someone to scan it with VCDS (vag-com) for any codes.

It would help to know what generation Jetta you have - 1999 is a funny year, because the MKIII went up into 1999, and had a 2.0L with a cap and rotor, where the 1999.5 went to the newer MKIV body style and had a 2.0L with a solid state ignition pack.

So, if it's an MKIII cap and rotor, pop the cap and inspect the rotor and the inside of the cap, check your wires and wire boots, and look at the color and electrodes of your plugs.

If it's the MKIV pack, they can develop hairline cracks in the thermoplastic which cause the spark to arc between cylinders or short out completely. The fix there is to replace the entire pack, or if you are in a bind, you can get a bunch of JB Weld and coat the entire top surface in JB weld.

There's a couple of things to check.

[SuperVWNut]

Thanks ... the dealer said it was two bad spark plug wires. Cost me two hundred bucks! But it is running nicely again. They also said that the check engine lamp had been removed so my next step is to have someone remove the cluster and replace the lamps so I can see when it is having problems.

[Rennwagen1]

Wait! Don't you know that is how we fix check engine lights around here?! WE REMOVE THEM!! Keep the faith!!