87 bonneville wont start
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From: allentown, pa--brooklyn, ny

Originally Posted by twentytwin
I checked spark again after charging the batt. and had spark the car backfired like it was out of time when I tried starting it I think it'* the timing chain and or gear
have you checked your crank sensor or harmonic balancer...
88, all of our engines have timing chains.
Now that I think of it, you just might have a bad timing chain or gears. The LG3 3.8 used in the '87s came factory with an aluminum timing gear that had nylon teeth on it, and would strip out, causing the car to jump out of time, or slip completely, causing it not to start at all. I would check into that before doing anything else. It was a common occurence in the 82-88 3.0 & 3.8 equipped A-Bodies.
Now that I think of it, you just might have a bad timing chain or gears. The LG3 3.8 used in the '87s came factory with an aluminum timing gear that had nylon teeth on it, and would strip out, causing the car to jump out of time, or slip completely, causing it not to start at all. I would check into that before doing anything else. It was a common occurence in the 82-88 3.0 & 3.8 equipped A-Bodies.
Originally Posted by 88bonnsse
Originally Posted by twentytwin
I checked spark again after charging the batt. and had spark the car backfired like it was out of time when I tried starting it I think it'* the timing chain and or gear
have you checked your crank sensor or harmonic balancer...
'87 are prone to jumping teeth more than the later Vin C versions so its possible that its not starting because of this. 93k miles is in the range for failure.
However, I still wouldn't count out a weak fuel pump yet. Before you tear off the front cover, check for fuel pressure at the rail. You can rent a fuel pressure gage from Autozone (you get your money back when you return it so its basically free) to see if you have the correct PSI (40-45 is good, a tad less like 38 is still OK).
THEN, if you have good fuel pressure I would suspect that its jumped time.
However, I still wouldn't count out a weak fuel pump yet. Before you tear off the front cover, check for fuel pressure at the rail. You can rent a fuel pressure gage from Autozone (you get your money back when you return it so its basically free) to see if you have the correct PSI (40-45 is good, a tad less like 38 is still OK).
THEN, if you have good fuel pressure I would suspect that its jumped time.
so I replaced the timing chain and gear the gear was destroyed with only one tooth remaining.I lined up the marks put it back together and still wont start someone said it could be 180 out still.and the cam sensor might have broke.Is there any way to test these things.
Originally Posted by twentytwin
so I replaced the timing chain and gear the gear was destroyed with only one tooth remaining.I lined up the marks put it back together and still wont start someone said it could be 180 out still.and the cam sensor might have broke.Is there any way to test these things.
1. I had only the front of my Bonnie up on jack-stands and the rear wheels on the ground and chocked to keep the car stationary. This caused me tobe one-tooth off on my alignment of chain and gear because I was assuming that if I aligned the marks at 12 O'Clock the gear/chain and engine would be sharing top-dead-center. But they were not sharing top-dead-center because the front of the car and therefore the X / Y Axis of the crankshaft itself were tilted up and back towards the rear of the car.
2. Facing the front of the engine, because the car was not setting level in the first place, the true center ( the perpendicular of the crankshaft) of the engine was not straight up and down at 12 O'Clock like I assumed, but was actually more like at 11:58, but I was aligning the match marks straight up and down to what looked like 12 O'Clock, which set the timing gear/chain a few degrees ahead of top-dead-center.
Once I realised my mistake and reconfigured the orientation of the timing gear/chain to true top-dead-center, my engine started like new.
You may be turned around 180 degrees, but I doubt it because the car should still fire somewhat because the ignition system, on my Bonnie anyway, fires a spark at compression and fires a lesser spark upon exhaust to burn any latent fuel in the cylkinder before it is vacated from the cylinder and exhausted.
You may even have the plug wires crossed in the wrong firing order.
I guess the cam sensor could be bad. I'd take it off and have it tested at your parts house if the offer that service. The cam sensor being bad should not prevent your car from starting though. If it were bad the ECM would sense that the sensor was bad and use a default mode to allow rhe engine to run. Replace it though if you have any doubts. It probably cost'* around twent to thirty dollars new?
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