Damaged SOMETHING with backfiring ...

Backpressure is a myth. Part of what a good exhaust system does in enhance cylinder scavenging. One cylinders pulse helps pull exhaust out of another cylinder. Second part is anti-reversion. You want the exhaust to go out and stay out. The muffler and converter help reduce the exhausts tendency to go the wrong way. The converter does two things. One is it helps reduce the stink and polution. Second is that it reduces the exhaust noise. A straight test pipe would be quieter than the hollowed out converter. Well that is my guess.

Timing marks. There is a zero degree mark there. You just do not know how to read it. Well I can't swear to that but that is what my owners manual says. Here is how you find it. Get your rotor to point close to number 1. Remove spark plug #1. Insert large screwdriver in #1 hole. Slowly turn crankshaft paying attention to screwdriver rising. Keep paying attention to screwdriver and watch it fall. Turn crank the other direction to get it back to top dead center. Look in timing hole which should be 1.25" or so big. If that hole is just 1/2" or 3/4" then you have a plug that needs to be removed. There is a mark on the flywheel. It is not close to the ring gear or the machined flat surface but below that. If you are good at reading the rise and fall of the screwdriver then you will see. You have to find it to confirm camshaft timing. Until you find it you are wasting your time. The manual also mentions making a mark 12 mm to the left if you want for 6 BTDC or 6mm to the right for 3 ATDC.

There is a pointer in the timing hole if you removed the plastic plug. It would rather hard and unlikely for someone to chip off the timing pointer. The pointer is just a nib. It is not some huge 1/2" big arrow with a white tip on it. It is smack dab center of the threaded hole on the side closest to the engine block. If you were looking at the machined back edge of the block and you used a square against the machined block and could read the center of the threaded timing hole you should see it. I played a carpenter and tileman in another life. I can usually see the center of something.

You need to get someone with a good camera to take a picture. I don't have a Rabbit anymore so I cannot take a picture. Crummy pictures from my Bentley.

I test vacuum advance and retard with a small hand help vacuum pump and a timing light. The newer Bently has the specs. Bedtime.

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Thanks again Jim! I found the mark AND the arrow. Guess what ... it was there the whole time! The arrow was actually formed into the threads for the plug. I'm assuming that the mark is the timing mark and not 0 degrees. And I set my timing under that assumption (used the idle speed from the sticker under the hood). It seems to run even better, and I'm certainly approaching

100% power, if I'm not already there. BUT there is still a fair amount of stink, and some smoke is visible especially after I rev the engine up to high rpms. Unless the backfiring really did hollow out the converter, something else must still be wrong. I put in a new air filter for the hell of it -- no change. I *was* assuming that it was the fuel mixture, but it seems to stink throughout the entire useable range of the mixture settings. I remember setting the mixture with an emissions sniffer on the tailpipe a few years ago, and I got the best readings on the lean side of "smooth" running. So that's where it is right now. Can I only adjust the mixture with an emissions tester hooked up? Also, I was going to buy this manual which only goes to 1983 -- the year of my rabbit in question: there any reason to pony up the extra $40 for the newer manual thatcovers 1984?

Is there any reason to pony up the extra $40 for the newer manual that > covers 1984?

nah - 1984 was a carryover year. wouldn't be anything majorly different in that.

> Is there any reason to pony up the extra $40 for the newer manual that >> covers 1984?

I am with Matt. There might be some minor thing with an 84.

I used a dwell meter to check the fuel mix on my 84. Someone has the procedure. My dwell meterdoes not have a 4 cylinder setting. I cannot recall if that required a bit of math including the number 2. Or maybe that was setting dwell on old points.

I have done a number of timing belts. I bet that I was off one tooth on a third of them. My new car specifies that you are to turn the engine two full revolutions to make sure you have the belt on correctly. If I had done that on the older cars I would have been at

100%. Engine will idle fairly well with one tooth off but you will know that the timing is off even if the ignition timing is correct. Power and torque are off enough to easily feel.