Stumbling Accel - Plug wires? Timing Gear?

I'd start by looking at the spark plugs,: lean, rich, oily, etc? then put in a fresh set and test drive, OK? end; not OK? then I'd look at the rotor and dizzy cap, carbon tracked? segments worn down? crusty build-up? and replace if above 45k miles, including air and fuel filters. Unfortunately, you can't feel things out, you check them whit test gear and know the truth: good, no good, same for wires (pull them out of cap to test and look, or anything in a machine: test it, in spec? keep it, out of spec? replace it. When in doubt, change it out.

I vote you deal with correcting that Cam Position Sensor fault. Wires might fail a wet test or there might be misfiring codes if it was plugs or wires. If the timing belt was messed with then make sure that the distributor (cam position sensor) is correctly adjusted. I adjust them by eye and had to pull the position pin on one distributor after installing a timing belt on a '94-97 2.0 engine. It threw a Cam Position code.

I just got through correcting some problems created by Firestone when they changed the water pump and timing belt on a '02 Jetta 2.0. Tensioner was loose and the cam jumped 3 teeth. Darn engine was still running and the customer did not mention anything about the power loss nor mileage nor noise from rattling components due to loose bolts. His complaint was that the car did not start, but did on the tow truck. That problem is just a faulty ign switch. Also his ign transformer failed the wet test. Oh and 3 out of 4 spark plug wire terminals were broken at the transformer end and I could not find those broken pieces.

I hate finding so many problems caused by others, and having to correct things that should not need correcting! grrrr So have someone recheck the work that messed with your engine's timing belt and also find someone that knows VWs PLEASE! lol

JMHO

A friend had a newer car suffer a huge lack of power but idled fine. A little 1/2" hose had popped off up by the air filter housing. This happened to be on a 2002 car but loose hoses can cause a car to run lean which will cause the car to stumble.

I have done a number of timing belts on 1980-1984 Rabbits. Every time I get the belt off one tooth the car will idle fine but as soon as I drive it around the block it makes little power. I go back and get the belt adjusted properly and the car runs brilliantly. Based on my past experience with slightly older gas VW engines with timing belts I vote for triple checking the cam timing. On the TDI the properly way to adjust requires a lockdown of stuff. You tension the belt and turn the engine two complete revolutions and double check. With the TDI if you screw up you have to rebuild or replace the head as you will bend valves if that belt fails or is significantly off. Two full revs of the engine turning in the correct direction will get alll the slack out of the belt. Better chance of getting it correct.

I hope those are not the original plug wires. How old are they (years and miles) $100 is cheap when you consider how much fuel is today and even marginal plug wires can cost you more in mileage than new wires would cost.

Plugs and wires are consumables. They wear out.

Now having said that, I would suggest you consider the possibility of a blocked fuel filter or a marginal fuel pump.

When was the last time the timing belt was replaced (years and miles)?

Generally it is poor economics to replace a water pump and not a timing belt or replace a timing belt and not a water pump. Most of the cost is shared. I am not sure about your specific engine, but many cars have engines that will be seriously damaged if the belt goes.

It appears (I could be wrong) your approach of trying to save money on auto maintenance is going to cost you far more than if you just followed the prescribed maintenance.

Thanks to ALL for your responses.

Not sure of wire set's age. Plugs are relatively new not over 3 mos. Light gray on the old ones, but they seemed to have been gapped wrong. (car was stumbling then too) Timing belt was in-fact replaced with water pump, but mechanic just kept the position where the last belt was.( I didn't think to ask him to verify TDC and reset it if it was wrong. ) What has to come off/ what is involved- for me to verify that the belt is in the right position? Or to check for a clogged filter/faulty pump?

Again, I know I need to get a good repair manual, but funds are shaky right now.

Gotta to use the correct spark plugs. Non-original ones can cause running problems!

Using chalk marks to change a belt, remove a belt, or replace a belt is not ideal. Spending another 10 minutes to confirm that everything is correct is the proper way. I know the procedure on my old Rabbits and on my TDI. Not sure what it is on your car but it cannot take but a few minutes to rotate the engine by hand and double check. Bentely manual is what I refer to. You may have a Chiltons or some other manual at the library that may show the procedure. On my cars I confirm the crankshaft is at top dead center. I confirm with either a pointer to a dimple on the camshaft gear (or a camshaft locking plate on the TDI) that the cam is correct. On the old car I refer to the distibutor rotor that it is pointing to the correct place. No distributor on TDI. On my Toyota it is similar except it has a timing chain.

This post describes what I did >