Shuts off while driving?

1995 CADILLAC SEVILLE

79,000 MILES • 4.6L • V8 • 2WD • AUTOMATIC

JOHNNY ALMARAZ

MEMBER
1 POST

I've changed the alternator 2 weeks ago and it is now stalling while driving. This happens at around 3-5 miles an hour or when i stop at a stop sign the engine shuts off. It turns on right away but i don't understand what happened. However, when i changed the alternator i had not taken off the battery and i accidentally touched the red wire of the alternator to a metal close to it and a few sparks came out from that. I don't know if that has something to do with this new issue.

Feb 17, 2023 at 12:27 PM

JACOBANDNICKOLAS

✓Experienced Mechanic
110,240 POSTS

Hi,

Chances are shorting the wire isn't causing this. If the battery was failing, I would think it is related to the alternator but since it starts right back up, it appears to be charging.

Based on the description, it sounds like an engine vacuum leak. Have you checked for leaks? If not, let's start with that.

Here is a link that explains how to check and repair an engine vacuum leak:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Also, take a look through this link as well:

https://www.2carpros.com/articles/stall-at-idle

Let me know what you find or if you have other questions.

Take care,

Joe

Feb 17, 2023 at 2:19 PM

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