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Engine won't start after serpentine belt broke

  #1  
Old 07-28-2009, 08:32 PM
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Default Engine won't start after serpentine belt broke

I have a 1997 2.8 V6 and the serpentine belt (ac, alt, ps) shredded while going down the road at 40mph. Everything just shut down. I had the car towed home and replaced the belt, but now the car won't start -- it just cranks over. I can smell fuel (and there's 3/4 tank), so I'd assume an electrical/computer problem. I unhooked the battery for about 5 minutes to clear any "shutdown" codes that may have been in the computer, but it still won't start.

I've checked all the idlers and they rotate freely with no play and I've pried back the timing belt covers to inspect that belt and it looks fine as well with no cracking, etc.

Any reason it shouldn't start? Why did it just shut down when the belt broke? Most cars will run on battery power for awhile...

Help!!!
 
  #2  
Old 07-28-2009, 11:44 PM
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what does it do when you try to start it?
 
  #3  
Old 07-29-2009, 12:44 AM
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Default It just cranks...

It just cranks over and never seems to want to fire. Not even a sputter. It's like the ignition isn't firing.
 
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Old 07-29-2009, 01:20 AM
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did it mess up a lot of cables or anything when it came loose? The 2.8 v6 which is what i have is an interference engine if im not mistaken. if it is the serpentine belt coming loose will tare up the engine and cause damage to a number of components and probably be costly.
 
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Old 07-29-2009, 02:08 AM
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This was the outer accessory drive belt -- NOT the timing belt.

I looked around and found no loose wires or damage in the belt path, but it sure shredded... The only thing I really see electrical that could have been damaged (but doesn't appear to be) is a thin 2 or 3 wire harness going to what looks like a temp sensor on the driver's side down low on the radiator. There just isn't much up front other than the fans.
 
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Old 07-29-2009, 04:32 PM
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Update: if I let the car sit for several hours and try to crank it over, it will sputter for about a second and then it just keeps cranking with no signs of ignition.

Any thoughts on a seperate ignition system problem that coincidentally occured at the same time or may have been caused by the alternator shutting down? Like maybe a power surge taking out the ignition module? Any thought on how to test the ignition system since there is a shield around the end of the plug wire? (I usually put a nail or screw in the plug wire and see if it arcs to the block when I crank it over for a quick test...)

I wish I could swap out some ignition parts like the module, coils, etc., but at nearly $300 for the coils and about the same for the module... BTW, anyone know where the module is physically located?
 
  #7  
Old 07-29-2009, 05:24 PM
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follow the plug wires, one end is the spark plug, one end are the coil packs. they are no different then regular plug wires and you can test them the same way.
 
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Old 07-30-2009, 02:29 AM
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Well, I just did a quick and dirty test -- I pulled #4 plug and it was wet with gasoline and when the engine cranked over there was spark, albeit a weak looking one. The more I crank it over,the more I smell gas, so I know the fuel pump is working. I can't vouch for all the injectors or plugs firing, but it's something. The ignition module is probably good.

I will attempt to pull codes tomorrow if I can borrow a scan tool and I'll do a compression test to make sure the valves aren't bent to heck. Beyond that, I'm not sure what else I can do (checking cam timing is a bit out of my depth and it appears I have to pull the whole front end apart to do so). Can you even see a timing mark to check ignition timing?
 
  #9  
Old 07-30-2009, 09:50 AM
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have you pulled off the timing cover and checked that the belt is ok? there is a timing mark on the head that should be pretty easy to see, but the one on the crank pully might not be that easy to get to. the only reason you would have bent a valve would be if the timing belt snapped or it jumped a few teeth.

how many miles are on the plugs? did they look worn? gapped properly?
 
  #10  
Old 07-30-2009, 07:19 PM
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Well, thinking it may be flooded, I pulled all the plugs and blew out the bores with my air compressor. Plugs all looked good, evenly gapped, and no fouling or electrode degradation. Unfortunately, I pulled a bonehead move and broke the electrode off of one of the plug wires on the coil end.

The engine started and ran for about 4-5 seconds before shutting down again. It sounded like a diesel VW Rabbit, although I don't know if that's because it's now misfiring on #5 or because of valve interference.

It won't restart again. The local auto parts stores won't loan a code scanner and I really don't want to buy one for $70-200 to use one time. Anyone in the Elk Grove, CA area that has one? Is there a way to manually pull codes (GM cars you can short two pins and it flashes out the codes with the CEL)?
 

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