EOC attempt FAIL. GM owners help?
 

I just picked up some lunch and was on the way back to the office. The highway on the route back has a big ol' hill, so at the top of the hill at 60mph I put the truck in neutral and killed the engine by turning back the key. After the engine died, I turned the key back to ON so that the steering wheel wouldn't lock. After my delightful coast, I popped the clutch in 5th gear to restart the engine...

At this point, the truck's computer went totally ape sh#t. Every light on the dash came on and blinked for about five seconds and the Security light kept flashing. I tried to crank the engine but nothing. This while I'm still coasting around 65mph of course. I had to pull the truck over, no PS or PB, let it sit for about five minutes and then it started just fine.

Have any other GM owners out there experienced this? Not sure if it's something specific to the dime trucks or just the manual transmission. Googling has this far found no results related to the security light flashing while restarting the engine at speed...

ive had the same issue with my ford focus. once had the car not restart upon multiple attempts with the starter. had it happen one other time and i turned the key back to off let sit for a few seconds and then turn the key and cranked off the starter. the good news is, when the event occurs i know it ahead of time via the security light turns on.

hopefully someone else can tell us more

Why didn't you start the car in neutral and then rev match to 5th?

My Hyundai Sonata did a similar Christmas tree light show when I did an engine off at a red light. I started up in neutral just fine but when I popped it into gear, the engine grunted and hesitated before giving me power.

No more of that for me. From now on, I wait until all the startup lights turn off before I move into gear.

The steering won't lock if you only turn the key back ONE click from the RUN position.

Is it possible you turned the car (computer) completely off by turning the key back too far, and that's what it didn't like?

Was this your first attempt at trying this - at 65 mph on the highway?

The ACC position on my truck is actually behind OFF, and you have to push the button to get it there. So clockwise you have ACC - OFF - ON - START.

I did find a similar situation on google from owners attempting to simply push-start an S-10. Apparently ANY time you start the vehicle, the key must be in the start position. So attempting to pop the clutch even in first gear, say due to a dead battery or bad starter, you must hold the key forward or the Security light will immobilize the vehicle... CRAZY!

SCNTN -

Ok, sounds like a security feature that didn't take into account manual shifter dead-battery bump starts. I would hypothesize that your Sonoma needs an injector-kill-switch or equivalent.

CarloSW2

I'm sure that I did some EOC using the key, but I just don't remember that far back. I know I never had your problem.

I've been doing EOC using an injector kill switch. The engine restarts properly whether I bump start or key start it. It will randomly light the CEL with an injector code. Then I reset the CEL with the Scangauge and continue driving.

I tried another test on the highway near my home. Apparently it's an issue with the speed as well - trying to start with the key rather than bump starting yielded the same result. Looks like EOC isn't an option for me. Doh!

SCNTN -

Here's a question. What happens when you do a "normal" bump start as if the battery is dead? Try to do it on a (safe and) gentle slope that allows you to get up enough speed for a 2nd gear bump start.

If it still goes bonkers then you can try to find a Chevy Sonoma forum and I gair-own-tee that someone has complained about this and *mayyyyyyyybe* someone else posted a workaround.

CarloSW2

Actually, this got me thinking... my dad had to push start me once with his truck when my battery died. Had to really get moving to turn over that 4.3, but it did start around 15mph without me turning the key to start. So my earlier findings on google don't appear to be entirely correct. This makes me think it may be totally speed related. I'll try bump starting at increasing speeds and see if perhaps there is an upper limit that triggers the security light.