Engine cuts off while driving

Tiny
DRETYME
  • MEMBER
  • 1983 PORSCHE 911
  • 124,000 MILES
While driving normaly engine shuts down, turn off ignitions turn over and restarts soon to fail again without warning
Friday, May 25th, 2012 AT 4:31 PM

3 Replies

Tiny
FIXITMR
  • MECHANIC
  • 9,990 POSTS
Does it do it cold or just when warmed up?
Was this
answer
helpful?
Yes
No
-1
Friday, May 25th, 2012 AT 4:44 PM
Tiny
FIXITMR
  • MECHANIC
  • 9,990 POSTS
If it's warmup related consider this. The Bosch CDI unit can go bad where it "locks up" and stops producing sparks under temperature stress. Once you turn the ignition to OFF it resets the box and it will work again for some period of time before the cycle repeats. The effect is strongly temperature-dependent.

To test whether lock-up is your problem do this: Once the car shuts down DO NOT turn off the igntion. Open the engine lid and listen to the whine of the CDI box and memorize its tone. Then turn the ignition to OFF and back to ON without starting the engine. If the whine now sounds different (lower pitch and louder) you have identified a lock-up condition.

If the whine sounds about the same after the power-cycling it confirms that lock-up is not your source of the problem.
Was this
answer
helpful?
Yes
No
+1
Friday, May 25th, 2012 AT 6:46 PM
Tiny
DRETYME
  • MEMBER
  • 2 POSTS
Warmed up, today I found a wire frayed behind the ignition switch, pull the switch and opened, all the terminals were exposed and went into disarray where do I find the order they go back in i.E. 50 15 x 30 etc.
Was this
answer
helpful?
Yes
No
Friday, May 25th, 2012 AT 11:27 PM

Please login or register to post a reply.

Sponsored links