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1997 Chevrolet Astro - Dies when turning left

When I make Left turns the engine either dies or runs very rough. Shut off engine and re-start all is fine. Found problem and would like to inform of solution.

Yes, please inform us of the solution that you found.

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Top of the head I’d say fuel pump. Does the problem happen when the tank is full or just when it’s close to empty?

The plastic cover over the crank sensor wires was pushed back. It exposed the wires, which over time rubbed against the motor mount sharp edge. When the van made a left turn the engine tilted to the right which made the exposed crank sensor wire touch ground. This would stop the signal and the engine would stall. Restarting with the van straight removed the short. In other cases the short produced an extra spark which moved the engine on the mounts and made the engine violently move from side to side. A scope on the coil wire showed the extra sparks at the time the engine was shaking. A bit of shrink sleeve and the re positioning of the protective plastic cover fixed the problem. This was after the distributor, ECM and crank sensor were changed.
I was about to junk the van until I instrumented with a tach, vacuum gauge, Oscilloscope and timing light. Got it running, disconnected the 120 volt power and drove in left turns in a parking lot until it failed. Returned to the ground power and observed the extra firing pulses. Once that was determined an inspection of the wires confirmed the problem. The van ran for another 30,000 after that.

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Yes, or a loose electrical connection, or… ?
But, because the OP has stated that he/she would like to inform us of the solution, I think it is worthwhile to wait for that info.

The OP didn’t express him/herself in terms you found acceptable. It happens to me all the time. It’s still no excuse for a non-answer.

… and yet, the OP finally revealed that the problem was indeed a bad electrical connection.

:+1:
:thinking:

1 Like

That was the answer. The frayed wire going to the crank sensor touched ground and prevented the signal to the ECM from firing the spark plugs. The crank sensor is designed to provide a ground signal at each rotation of the crank pulley. There should be only one per revolution. When the engine shook, it produced multiple ground signals causing the extra spark or grounded the crank sensor signal so there were no signals going to the ECM.
It was not a “bad” electrical connection, it was a frayed wire.