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Posted (edited)
On 8/24/2021 at 3:58 PM, Joe Brooks said:

Has anyone has the “shim” installed on the cam shaft position sensor long enough to know if that fixed the issue?  

I just had mine shimmed. Had a no start 2 days later and now the thing also reeks like coolant. Today they tried the ECM re-flash. Will have to wait and see if that does anything.

Edited by Jessie D
Posted
On 10/5/2021 at 12:57 AM, Hello32 said:

I picked up my truck. Got their once service closed so didn’t get a chance to speak to the advisor. Receipt says reprogram ecm that was released on 10/04/21 and perform setup. One thing i noticed right away was the truck cranks for longer now. It makes you feel like your going to have an extended crank but starts up.

Yes I noticed that too. It seems to go for an extra second or so now.

Posted

Truck now has 5200 miles with 4 crank/no start episodes. Going next Friday for oil change and the ECM flash. Will update afterwards. 

Posted

My dealer thought it was one of the relays so they replaced it. Unsurprisingly, I had a no start recently.  

Posted

I just got the ECM update today. Any potential issues with premature wear with the longer crank time?

Posted

Wow, this thread blew up since I looked here last.  Dropped off my 21' Sierra AT4 3.0 Duramax for its third trip to the dealer for the Crank / No Start.  I've already had the ECM reprogrammed and the issue has even happened to the Service Tech during the second visit while they had equipment hooked up to it, they saw some sort of steering column / ignition code.  They reprogrammed the ECM again.  Still happening.  I've given them plenty to look into from what I've learned on this thread so thanks for all the info. 

 

One thing my Service Rep pointed out today is that in order for them to continue with any work I'm responsible for the $185 in labor costs for them to remove the aftermarket theft deterrent system (wiring / connectors) that was installed at the original dealership that I had purchased the truck from.  Long story for a different thread...  🙃

 

I'll report back with details once I have them. 

Posted (edited)

'I just got the ECM update today. Any potential issues with premature wear with the longer crank time?"

 

My brain actually hurts this question is so stupid

Edited by youcantkeepup!
Posted
1 hour ago, youcantkeepup! said:

 

My brain actually hurts this question is so stupid

I almost took your troll bait but then me and everyone else on here would have to listen to you spout off your bs resume and self fluffing. Keep this topic informative. 

Posted

Sorry but.......

Here's informative for you. The more something is used, the faster it wears out.  

Posted

LOL “youcantkeepup!” doesn’t need to fluff himself, you do it for him. Maybe someone who isn’t the second do-it-himselfer can chime in with meaningful information. 

Posted
22 minutes ago, WontStart said:

LOL “youcantkeepup!” doesn’t need to fluff himself, you do it for him. Maybe someone who isn’t the second do-it-himselfer can chime in with meaningful information. 

One bit of misinformation that my saleman had been told by the service department, is that the auto restart system does not cause wear on the engine starter.   I think this bit of 'folklore' comes from the fact that hybrid cars use the big electic motor to restart the gas engine.   If you notice when riding or driving a hybrid the starting of the gas engine is almost undetectable since it is so smooth a transition.   Our truck use an old fashion starter to start.   It and the flywheel gear, bendix and starter gear teeth all wear incrementally with each start.

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