Help with DOD cam swap
 

ok guys im doing a cam and head swap on my 08 5.3 with DOD. i got everything buttoned back up and cranked her up for the first time.... Nothing it fires but wont continue to run... i know that the first and last cylinder on the driver side of the engine are firing because the header primaries are hot after cranking a few time. on the passenger side it is the opposite the middle two primaries are hot and the outer two are cold... any ideas guy ... did the lifter trays get put in wrong.....i will try to trouble shoot it more tommorow after work but thats all i have for know

First off, tell us all the parts you changed, in detail.

Second, the cylinders you named as "hot" on the primaries are the cylinders that (formerly) had DOD/AFM.

Did you remove the LOMA intake cover and install the LS2 cover?

Did you mark your injector harness plugs to correspond to the appropriate cylinder?

Ok i replaced the cam, pushrods and springs. i did not change the valley cover and i left the dod lifters. i did not mark the injector harness because you can pretty much tell which ones go where because the length of the harness

is the injector harness color coated

make sure in the tune that DOD is turned off!!!!

yeah charlie diabled it

You left in the DOD lifters????? Holy crap. Okay, there could be two problems I can think of:

1) You installed the lifter trays in the wrong bores. As you may know, the DOD lifters when you look into the lifter tray have a big spring on them, 2 lifters side by side. These are the lifters that cannot fall out of the tray.

The DOD lifters go into drivers side cylinder # 1 and # 7 (most front and most rear).

and

Passenger side cylinders #4 and # 6, (the two middle cylinders).


Honestly, is sounds to me like you put the passenger side trays in the drivers side, and the drivers side trays into the passenger side. Completely backwards. The DOD lifters are now not aligned with the oil pipes to the LOMA, thus not getting any oil to open the valves. And....now the other 8 standard lifters are getting TOO MUCH oil.

Or,

2) You didn't connect the electrical connector to the LOMA unit (valley cover), and the DOD solenoids aren't passing oil to the lifters.

Or,

3) Both of the above.

In reality, you should have never put those lame-ass DOD lifters back into the engine. You had the heads off, you should have put LS7 lifters, trays and the LS2 valley cover on.

I'm not being a dick, but man oh man you went in that far and then reinstalled a screwed-up design back into your engine?

Sounds like you need to pull the intake manifold back off, see if the electrical connector is plugged in the LOMA. If it is, then unfortunately you are pulling the heads off again, to fix the real problem.

This time buy the right stuff and do it for real. Believe me, you would have hated the truck anyway after you got it running with the DOD lifters. They cannot handle a real camshaft lobe. In fact, the DOD cam has special lobes just for the DOD lifters/cylinders, and running a normal cam on them freaks them out and collapses them, and sets of p0300 codes, and makes the engine run poorly.

Remove those lifters.

If you are really tight on cash, just buy 8 standard 5.3 lifters and LS7 trays, and re-use the 8 normal lifters that are in your engine. You need to buy the LS2 valley cover also.

Ok dont get me wrong im not trying to argue but then why ar ethe headers on the 1, 7 and 4, 6 get then obviously they are fireing or is it because now they have the standard lifter in there and the 3,5 and the 2, 8 have the dod lifters

also if i just changed the lifter and the dod was turned off would i still need the ls2 tray

1) Yes, you have the standard lifters in the DOD holes. Like I said, sounds like you installed the passenger side trays on the drivers side, and vice versa.

2) Yes, you need the LS2 cover to block the oil pipes of the engine block, otherwise the lifter galley oil will backfeed into the LOMA solenoids and reverse circulate right to your oil pressure sender, collapsing the little plastic screen in the LOMA, eventually causing a failure.

The engine would have ran if you had the lifters in the correct hole, and the LOMA connector installed.

I am guessing you are also having intake backfires, or loud bangs from the engine right now when trying to make it run?

The only other thing it could be is that the injector harness in not on correct, but cylinders #1 and #2 (front of engine) have the injector plugs coming from the vertical looms, and the rear cylinders have the other cylinders coming from the rear looms, thus you could sort that out easily.

Good luck.