NEED HELP Crank No Start 5.3L V8 Envoy Denali

[GaigeBarker]

2006 GMC Envoy Denali, 5.3l v8 4l60e

- Exhaust setup
- Cold air intake w heat shield
- New starter
- New battery
- new alternator
- new oil sensor

that’s about it for modifications and or new parts recently put on.

For the last 3 months of having this car every-time I put a full tank of gas in, it it will have a small rough start and sound choppy at first. The other day I went to start it and it took a good 10 seconds for it to start up. After it started it was rocking me side to side and sounded as if someone put a sport cam inside my car while I was sleeping. After 10 seconds of it running it went away, during that time there was a lot of smoke coming out of the exhaust, it went away fairly quickly. It started to idle smooth with occasional spikes.

After I let it warm up for a few min I take it to the gas station, coming to a complete stop my car is revving to 2k rpm in drive at a full stop. It was forcing me to go forwards and almost hit someone. When I go to park or neutral it will do the same thing.

I turned the car off fearing it would try and rev higher and blow up, ever since I turned the car off and filled it with gas that day. It will not start AT ALL NOW. I had to have my dad pull me home in his truck with a strap. Already used all my AAA towes with this truck this year.

About a week ago I got a crank shaft position sensor code but it went away, I also have a evap purge code. Only codes that will affect anything. Now no codes will appear. My battery keeps dying while trying to start the car. Battery was fully charged and wouldn’t start the car either. I tried 20 times and died again, I’m about to fully charge my battery once again and try again.


What you guys think it could be??? My ignition lock cylinder is also not opening with charge which is new after this happened. Maybe it is my battery?!

 

[GaigeBarker]

I just bought a evap purge canister, going to replace that today. P0496 code is a code that keeps popping up. The crank shaft sensor code popped up only once. And hasn’t popped up again. I’m guessing it’s an intermittent failure for that, and the canister is stuck open flooding my engine maybe??

 

[Chickenhawk]

I would check the battery cables first, then load test your battery. It may be new but there is a certain amount of failure rates with new batteries. If the voltage drops below 5 volts while trying to start, it can display exactly those symptoms when all the settings for engine control are lost and it must go to default settings.

I would also change your cam and crank sensors. They are not very expensive. But the battery cables and battery are the first suspects here.

 

[mrrsm]

Check the Ground - Bonding Strap on the Passenger Side Rear Engine Head of the 5.3L Motors where it should connect to the Firewall. This is a problem that can creep up from time to time, causing a Crank - No Start situation by seeking a Ground back to the Negative Battery terminal by other means.

Check on getting information on your 2006 GMC Envoy Denali via THIS Link for the Final Grounds PDF provided by @jmonica most recently covering the 4.2L AND the 5.3L GMT360 SUVs to download and refer to it for more information:

Electrical Ground locations

While troubleshooting a bad ground I came across some scans of the service manual regarding electrical ground locations for our platform posted on another site. This includes both short and long wheel base, as well as both 4.2L and 5.3L. Credit goes to Wex...

gmtnation.com

 

[Mooseman]

I also have a evap purge code.

For the last 3 months of having this car every-time I put a full tank of gas in, it it will have a small rough start and sound choppy at first.

I'm thinking that your charcoal canister is saturated with raw fuel and the evap is sucking it into the intake, hence the rough run, but it should still start. Maybe try disconnecting the evap purge valve and plug the vacuum line to the intake. It could be flooded. Try using the flood clearing mode by pushing the gas pedal to the floor and crank it. Failing that, I would check the usual methods for a crank no start.

Cranks but won't start

 

[christo829]

My girlfriend's sister's Traverse had the same symptoms, and finally threw a purge valve solenoid code. Once I replaced that, the issue cleared up. I'll get similar problems if I've been parked with the passenger's side of my TB a lot lower than the driver's side. It'll start ok, but if I stop for fuel within half an hour or so of being parked that way, it'll throw the same code, run rough, and at high idle, until I clear the code. That aligns with Mooseman's saturated canister. So if you've already replaced the canister, the purge valve may not be operating properly.

 

[mrrsm]

Also ...try pouring in a BIG Bottle of Chevron Techron into the Fuel Tank to emulsify any water condensation or other contaminants laying down in the bottom of the Fuel Tank.