Rebuild & dod afm delete no start

[TTRZ71]

I have a 08 Tahoe z71. I had a 09 block rebuilt. New pistons, rings, all bottom end bearings, btr stage 1 cam, new lifters, new refurbished heads. DOD/AFM delete. Put all back together. Got it started with the old galley cover connected, ran for about 45 sec to a minute then shut off on its own and won’t start again. Threw a code for crank sensor. I’ve replaced both the cam and crank sensors. Still nothing. Won’t start again. I’ve checked all my grounds, I have 60lbs at the rail. Cranks but won’t start. I also ran a separate ground to the injector harness and nothing. Any help would be great. Thanks in advance.

 

[iamdub]

I have a 08 Tahoe z71. I had a 09 block rebuilt. New pistons, rings, all bottom end bearings, btr stage 1 cam, new lifters, new refurbished heads. DOD/AFM delete. Put all back together. Got it started with the old galley cover connected, ran for about 45 sec to a minute then shut off on its own and won’t start again. Threw a code for crank sensor. I’ve replaced both the cam and crank sensors. Still nothing. Won’t start again. I’ve checked all my grounds, I have 60lbs at the rail. Cranks but won’t start. I also ran a separate ground to the injector harness and nothing. Any help would be great. Thanks in advance.

Checked your fuses, particularly the PCM ones? What is/are the actual code(s) that you're getting? Did you clear the code after replacing the sensors?

 

[TTRZ71]

Checked your fuses, particularly the PCM ones? What is/are the actual code(s) that you're getting? Did you clear the code after replacing the sensors?

I’ll check the fuses today. My tuner was the one that told me about the crank sensor code. I don’t know exactly what code it threw and it hasn’t been cleared yet.

 

[swathdiver]

I have a 08 Tahoe z71. I had a 09 block rebuilt. New pistons, rings, all bottom end bearings, btr stage 1 cam, new lifters, new refurbished heads. DOD/AFM delete. Put all back together. Got it started with the old galley cover connected, ran for about 45 sec to a minute then shut off on its own and won’t start again. Threw a code for crank sensor. I’ve replaced both the cam and crank sensors. Still nothing. Won’t start again. I’ve checked all my grounds, I have 60lbs at the rail. Cranks but won’t start. I also ran a separate ground to the injector harness and nothing. Any help would be great. Thanks in advance.

60 psi running? Only supposed to be 43.5 psi. What was your oil pressure?

 

[TTRZ71]

60 psi running? Only supposed to be 43.5 psi. What was your oil

I have a 08 Tahoe z71. I had a 09 block rebuilt. New pistons, rings, all bottom end bearings, btr stage 1 cam, new lifters, new refurbished heads. DOD/AFM delete. Put all back together. Got it started with the old galley cover connected, ran for about 45 sec to a minute then shut off on its own and won’t start again. Threw a code for crank sensor. I’ve replaced both the cam and crank sensors. Still nothing. Won’t start again. I’ve checked all my grounds, I have 60lbs at the rail. Cranks but won’t start. I also ran a separate ground to the injector harness and nothing. Any help would be great. Thanks in advance.

Update!!! I checked all the fuses and it seems like I have absolutely no power to the fuel pump fuse. The fuse is good but no power in that circuit. However I’m still getting fuel to the rail.

 

[TTRZ71]

60 psi running? Only supposed to be 43.5 psi. What was your oil pressure?

It’s not running. Just when I crank it reads 59-60lbs

 

[Dustin Jackson]

I had a similar thing happen to me, ended up being a lose ground on the front of the passenger head but you said you checked grounds already so not sure

 

[j91z28d1]

you have fuel pressure but are the injectors openings, check for wet plugs and do you have spark?

if fuel and spark(plus non fouled plugs) and no start. timing would be next

 

[swathdiver]

Get a Tech-2 on it and see what's going on inside.

 

[Geotrash]

I have a 08 Tahoe z71. I had a 09 block rebuilt. New pistons, rings, all bottom end bearings, btr stage 1 cam, new lifters, new refurbished heads. DOD/AFM delete. Put all back together. Got it started with the old galley cover connected, ran for about 45 sec to a minute then shut off on its own and won’t start again. Threw a code for crank sensor. I’ve replaced both the cam and crank sensors. Still nothing. Won’t start again. I’ve checked all my grounds, I have 60lbs at the rail. Cranks but won’t start. I also ran a separate ground to the injector harness and nothing. Any help would be great. Thanks in advance.

What was the code? P0335? Does the engine sound like it's cranking normally or has it developed any weird rhythms during the cranking process? Did you use the 3-bolt version of that cam and if so, did you also use the correct 58x reluctor sprocket?

Start with the basics. Trace the wiring for the crankshaft and cam position sensors. If you're using a 3-bolt cam, it's easy to overstretch the cam sensor wiring when using the adapter, and/or the harmonic balancer can nick the wires if they're not repositioned just right. If no visible physical damage to the wires, then test for continuity at each end of the wires (you may need a wiring diagram to figure out where they terminate). If everything checks out, then the next step is to pull the timing cover and make sure everything is still lined up the way it's supposed to be.

 

[Geotrash]

Here's a wiring diagram for ya for the sensors to the ECM

And another for the VLOM, sensors and ECM

Don't forget to check the engine fuse in the underhood fuse block.

 

[TTRZ71]

Here's a wiring diagram for ya for the sensors to the ECM

View attachment 400799

And another for the VLOM, sensors and ECM

View attachment 400800

Don't forget to check the engine fuse in the underhood fuse block.

Ty so much for the assistance. I went into full diagnostic mode yesterday. I found that I have spark to the four coils on the driver side. But the four on the pass have no spark. I swapped out two of the coils to the other side and they had spark. Tells me my coils are good. I have power to the harness on the pass side but no spark. I want to reiterate that I got the truck running once. For about 1 min or so. Turned off and now where here lol.

 

[iamdub]

Ty so much for the assistance. I went into full diagnostic mode yesterday. I found that I have spark to the four coils on the driver side. But the four on the pass have no spark. I swapped out two of the coils to the other side and they had spark. Tells me my coils are good. I have power to the harness on the pass side but no spark. I want to reiterate that I got the truck running once. For about 1 min or so. Turned off and now where here lol.

So, a crank sensor code and the right bank coils are dead. If I weren't on my work laptop I'd be able to look up the wiring schematics. But, there's a common ground issue that will kill the left bank coils. Perhaps you have a loose ground or damaged wiring on the right bank that caused you to lose the CKP sensor and the coils? CKP is on the right bank but I don't recall any grounds on that side other than the one on the RH cylinder head in the front, above the tensioner. The other circuit that comes to mind is the one that feeds the CKP and starter solenoid. It runs along the oil pan and across the front, behind the crank pulley in that plastic shield.

 

[Geotrash]

Ty so much for the assistance. I went into full diagnostic mode yesterday. I found that I have spark to the four coils on the driver side. But the four on the pass have no spark. I swapped out two of the coils to the other side and they had spark. Tells me my coils are good. I have power to the harness on the pass side but no spark. I want to reiterate that I got the truck running once. For about 1 min or so. Turned off and now where here lol.

I agree with Chris, that there is a ground issue. Check the ground on the front of the pax side cylinder head. There should be two wires that terminate there. One of them is for the coils on that side.

 

[muncie21]

Not sure if this motor is the same as LS1. However, the LS1 has a ground on the back of the driver's side head.

 

[TTRZ71]

Something went wrong with this build. Ended up being catastrophic failure in two cylinders. Hence the no start. After a lot of testing and diagnosing all electronics checked out okay.

 

[Dustin Jackson]

@TTRZ71 Sorry to hear that, what’s the current status and plan of action?