Dies when not given gas?

2006 BUICK RENDEZVOUS

158,000 MILES • 3.5L • V6 • 2WD • AUTOMATIC

WHOPPEY

MEMBER
1 POST

I'm trying to help a friend who recently got screwed over by a very expensive "mechanic". The main problem he's having is the car idles kinda rough and it dies whenever he lets off the gas at red lights, stop signs, etc. I was thinking a dirty idle air control valve or throttle body. I checked for vacuum leaks and everything was good there. Its got newer sparkplugs and wires from previous mechanic.

Aug 29, 2025 at 6:15 AM

STRAILER

✓Experienced Mechanic
55,065 POSTS

So we need to check the engine compression which will cause this kind of issue. Also, you must make sure the correct spark plugs were installed. Here is a guide to help with the testing

https://www.2carpros.com/articles/how-to-test-engine-compression

These are the spark plugs that need to be installed.

ACDelco 41-101 (Professional Iridium) - this is the OEM plug GM spec’d for that engine.

Gap: 0.040 in (1.0 mm)

Please upload what the spark plugs look like so I can see them to tell what might be happening as well when you get back to us.

Aug 29, 2025 at 11:05 AM

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