Engine Won't Start After Timing Belt Fiasco!

[engrlks]

Hopefully some problem solvers out there that can help a brotha out:

I replaced the timing belt on my 91' 325i (in addition to pump, belts, tstat, cam seal, valve adjustment). The timing mark on the crank was ~1 tooth off from the corresponding mark on the cam....so I assumed the harmonic balancer must have slipped over the years and I adjusted marks to match (the car has ~140k and has never had a timing belt change). The engine fired up great after reinstalling everything, but had a strange 'knocking' noise that increased with throttle/speed. There was a slowly increasing loss of power over the next few drives. Took it to a (euro) mechanic and he said it didn't sound too abnormal (not piston slap), and maybe it just needed oil. On the way home, the knocking grew louder and the engine completely died mid-drive.

I got a tow back to the house, ripped everything apart, and found that the cam was extremely loose (wobbling about) and cracked the distributor rotor into pieces. I had removed the rotor already during the timing belt change, so I know it wasn't a preexisting issue. After replacing the rotor the engine still does not start : Its definitely related to the mystery knocking (loose cam / rotor?).

http://www.youtube.com/watch?v=I5jq2S0Wfj4

-Spark Test shows a bright blue spark
-Spark plugs do smell like gas
-Engine cranks (shown in the video)
-No apparent vacuum leaks
-Stomp test doesn't yield any codes
-Engine worked fine after tbelt change, so it shouldn't be the crank sensor
-Maybe its that 50A fuse near battery? I think the 6-gauge wire feeds the ecu, pump, and injectors.


This situation is killing me, any ideas?

[billybobjoseph]

What do you mean by "extremely loose cam"? There's a bearing where the shaft goes through the head. You can pull the valve cover and the rotor ( and the plastic bowl with a hole behind it ) and inspect it. Also I'd be super nervous about pistons hitting valves although I know you can turn the motor by hand when it's one tooth off.

[billybobjoseph]

Oh yeah you gotta pull the cam bearing seals as well to see the bearing.

[StereoInstaller1]

Why would you use the harmonic balancer to set cam timing?

Oh wait, did you use the Bentley? I hope not, it is wrong.

You are supposed to use the notch on the front of the engine that is right by the crankshaft (NOT the harmonic balancer), there is a mark on the crank at #1 TDC, and the cam marks you already found. That picture in the Bentley is wrong.

[Kershaw]

the cam was loose?

hmm wat.

[engrlks]

I meant the cam sprocket (I had taken it off to replace the seal and oring) was loose because I must have forgot to tighten the star head bolt when putting everything back on. It looked like the timing belt was moving back and forth on the sprocket causing it to work its way free with every rotation, so I readjusted everything until the belt was generally in the same path when cranking.

I did use the notch on the engine by the crankshaft. Here is what everything looked like before I adjusted the crank:


The engine ran fine after I adjusted everything, then the knocking started which I suspect was the broken rotor hitting something:


So if I'm getting a spark and the engine is cranking, do you think I blew a fuse for the fuel pump or ECU? Is it possible the marks were off to begin with, and adjusting it even slightly caused piston slap?

[Kershaw]

check your fuse box. its easy enough.

adjusting an engine back to TDC wont cause piston slap. im keen to think that the rotor just broke on its own... but i've never seen that before. you'd have a crap ton more problems (like bent valves and broken rockers) if your came came loose....

[engrlks]

check your fuse box. its easy enough.

adjusting an engine back to TDC wont cause piston slap. im keen to think that the rotor just broke on its own... but i've never seen that before. you'd have a crap ton more problems (like bent valves and broken rockers) if your came came loose....

I just checked the fuses (all except the larger relays) and they are fine. another thread mentioned something about a shrink wrapped fuse in the rear of the car near the battery (on the 6 guage wire coming off the positive terminal) controlling dme and fuel pumps. I didn't cut the shrink wrap off yet, but it feels in tact.

[billybobjoseph]

I've heard that some aftermarket caps have an incorrect inner diameter between the nodes and that a rotor can break because it hits one. Although looking at the pic of that rotor.....

[Myster-E]

holy fucking shit

[engrlks]

I just pulled all the spark plugs and I smell fuel on all of them....so its getting fuel....its getting a spark.... I'll try cranking everything to TDC in the morning and starting, maybe that will do something.

I could just fill the tank and tires with acetylene gas and give it light.

[billybobjoseph]

Smell fuel - Leaky injectors?

[engrlks]

Smell fuel - Leaky injectors?

I just tried starting it too many times.

[engrlks]

still not working even when starting from TDC. All the spark plugs have been replaced, compression test is fine, and no wires have been mixed up going to the distributor. After replacing the spark plugs today, I just turned the ignition on (didn't try to crank it) and the muffler backfired and the electrical system went dead (no lights, no engine crank, etc.). I disconnected/reconnected the battery, and I'm back to original situation of cranking but no start.


Knocking noise--->rotor breaks--->engine shuts off---->replaced everything---->engine still doesn't work.

[Gruelius]

bad coil? idk. just try swapping shit i guess.

that muffler shit sounds wierd. is your engine ground connected?