Engine shuts off when transmission is shifted into drive

1994 CHEVROLET BLAZER

220,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC

CHRISTINA MICHELE PECK

MEMBER
10 POSTS

My vehicle has a problem idling that started intermittently when I stopped too fast. Eventually I had to put into neutral to keep from stalking when I stopped. Then I parked it for a couple years. During that time, I would start it from time to time. Then one day it just began stalling after starting. It idled a few seconds then shut off. Start right back up and die. Did a tune up but couldn't get timing right. After a few months I went at it again to no avail. Thought carburetor so I bought a brand new TBI, me jets. Still same issue. Replace IAC, new distributor, cap, rotor, plugs, wires, ignition module, MAP, O2 sensor, EGR, fuel pump, fuel filter, coil, battery, air filter and more. So finally put into a shop because the issue remained. So, the shop was successful in getting it timed and idling perfectly. Sounds great. Put into drive and she immediately stalls. All vacuum lines are good. Been 3 weeks in shop and they're stumped. What could be going on?

Mar 22, 2022 at 3:02 PM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

The fact that this is a stall in gear we need to suspect a possible torque converter issue. If this is locked up, then it will stall at idle only in gear.

This would also explain why it would stall when coming to a stop. Think of this like coming to a stop on a manual transmission and not pushing the clutch in.

I am attaching a number of things that will help point to the possible issues but if you have a scan tool, we can monitor the torque converter clutch slip and application. It should be disengaged when put into drive.

Also, we need to check for codes and make sure you don't have any.

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

Lastly, we need to check for an actual vacuum leak using this guide even if the vacuum lines are ok as you could have a manifold leaking.

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

Please let us know what you find with this info, and we can go from there.

Thanks

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Mar 23, 2022 at 8:11 AM

CHRISTINA MICHELE PECK

MEMBER
10 POSTS

Idles great. Starts every time and stays idling. Shift into drive immediately stalls.

Mar 24, 2022 at 9:41 AM (Merged)

JACOBANDNICKOLAS

✓Experienced Mechanic
110,240 POSTS

Hi Christina, this can be several different things. One of the most common causes is an engine vacuum leak. However, I just need a little more information from you.

First, when you place it in drive, does the vehicle jump (similar to what a manual transmission would do if the clutch was popped)? Also, are there any strange odors or smoke from the exhaust?

Do me a favor. Take a look through this link and let me know if it is at all helpful:

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

Next, what I need you to do is check for diagnostic trouble codes. This vehicle has an OBD1 system that doesn't require a scan tool to retrieve codes. All you will need is a short jumper wire or even a paper clip.

Follow the directions in this link and let me know if you were able to retrieve codes and what they are:

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

Let me know what you find or if you have other questions. One last thing, I just wanted to confirm this is a full-size Blazer. I don't see them too often anymore. LOL

Take care,

Joe

Mar 24, 2022 at 9:41 AM (Merged)