2008 Chevy Tahoe ppv crank not start

[Jooseevh]

2008 Chevy Tahoe crank no start it started before it just had a cylinder 4 misfire but would still start and run

To fix the misfire I replaced

LS7 Style Lifters Cylinder Head Gasket Cylinder Head Bolts Aftermarket OE Style L92 Valley Cover TSP/GM

Single Bolt non DoD Stock Camshaft Exhaust Manifold Gaskets Header Bolts LS Camshaft Retainer Plate and Bolts Gm LS2 Chain Damper Gm LS2 Lifter Trays Timing Cover Gasket and Waterpump Gaskets Oil pan gasket replaced Oil pressure sensor replaced Throttle body and sensor replaced



During this build I messed up in the worsts ways. I placed the alternator block right onto the pom wire harness causing to damage wire going into pcm. I fixed damaged wire by soldering it down with an extra 22 awg cable wire.



I spilled coolant onto the PCM when uninstalling radiator.

Cleaned it dried it off.



I recharged my batteries and at the time of placing them back in I connected the battery cable backwards. So I changed the mega fuse already and checked my fuses. Fuses are good.took battery back to autozone to get tested they said it's good even though a chunk came off.



At one point it was throwing codes P2119 - which I replaced throttle body and throttle body sensor to fix



also had got a p0690, C0561 and p2544 which ssuming it had to do with the battery plugged backwards ind damaged wire.



Still no start just cranks.



Currently no DTCS showing up

I have check for basic spark, fuel and compression anu timing they all checked out doubled checked.



Out of ideas what to do next before taken it apart again.



I did tune out Dod with Hp tuners and still nothing.

 

[j91z28d1]

ouch. you've had a rough time of it.

I have no idea what all putting the cables on backwards could cause. but I'm just curious, you say you have hptuners. can the scanner connect to the ecm and read live data? that would at least be a good sign the ecm is alive.


how did you check for spark and fuel? it would seem like fuel and apart would at least give you some kinda firing.

 

[rdezs]

It should have blown the diodes out of the alternator. As for everything electronic... That's a real tough one. You're definitely going to need to watch the live data. And command the various systems to see what's working and what's not.

I'm assuming you put a new oil pump in and primed the system? Do you see a rising oil pressure while cranking over?

This is probably a scenario where a tech 2 will be the most useful. Not sure if the HP tuners has all the capabilities you might need.

 

[Jooseevh]

It should have blown the diodes out of the alternator. As for everything electronic... That's a real tough one. You're definitely going to need to watch the live data. And command the various systems to see what's working and what's not.

I'm assuming you put a new oil pump in and primed the system? Do you see a rising oil pressure while cranking over?

This is probably a scenario where a tech 2 will be the most useful. Not sure if the HP tuners has all the capabilities you might need.

I did not put a new oil pump in and didn't prime oil in either. With that and the diodes blown on alternator do you think that’s what it is? I’ve replaced mega fuse also and cleaned ground spots everything electrical in the car works fine haven’t found anything off

 

[Jooseevh]

I did not put a new oil pump in and didn't prime oil in either. With that and the diodes blown on alternator do you think that’s what it is? I’ve replaced mega fuse also and cleaned ground spots everything electrical in the car works fine haven’t found anything off

the gauge for oil pressure on dash goes up after attempting to start then back down to 0

 

[rdezs]

If the gauge is picking up oil pressure then the prime would have been unnecessary.

I would think that it would start even with the alternator dead.... It just wouldn't charge worth a damn.

Did you perform a CASE relearn?

 

[rdezs]

Did you look for any fusible links down by the starter?

 

[rdezs]

And was the mega fuse blown?