Another 6.2 for 5.3 swap going on.

[PatDTN]

Too late. I was forgetting that when I hit start my Tahoe will take over and crank it until it starts. Which it did almost immediately. In a panic I glanced at the oil pressure and I had 60 psi. The most the 5.3 had been managing was 40 on the highway turning some revs.

I had a pretty bad exhaust leak where the right manifold connects to the exhaust. I only had 5 of the nuts for those studs and what I thought was going onto the odd one was the wrong thread and had stopped while I tightened the other two. I found a correct nut and backed things loose and drew it up evenly for a snug fit.

At this point I'm trying to figure out why it started and ran for a few minutes then cut off. My guess is it's to do with the partial programming I got done and some signal the computer isn't seeing. Of course I got backed out of my nice warm garage into the cold rain when it quit.

That run showed me the exhaust leak and knew I had some crawling to do. It took 45 minutes but I managed to get it pushed back in up a slight grade by myself. Then I fixed the exhaust.

While I was doing that I kept getting dripped on from a coolant leak somewhere around the back of the right head. Gotta figure out where it's from.

 

[Tonyrodz]

Too late. I was forgetting that when I hit start my Tahoe will take over and crank it until it starts. Which it did almost immediately. In a panic I glanced at the oil pressure and I had 60 psi. The most the 5.3 had been managing was 40 on the highway turning some revs.

I had a pretty bad exhaust leak where the right manifold connects to the exhaust. I only had 5 of the nuts for those studs and what I thought was going onto the odd one was the wrong thread and had stopped while I tightened the other two. I found a correct nut and backed things loose and drew it up evenly for a snug fit.

At this point I'm trying to figure out why it started and ran for a few minutes then cut off. My guess is it's to do with the partial programming I got done and some signal the computer isn't seeing. Of course I got backed out of my nice warm garage into the cold rain when it quit.

That run showed me the exhaust leak and knew I had some crawling to do. It took 45 minutes but I managed to get it pushed back in up a slight grade by myself. Then I fixed the exhaust.

While I was doing that I kept getting dripped on from a coolant leak somewhere around the back of the right head. Gotta figure out where it's from.

At least you got it running, so that's something. Good job.

 

[iamdub]

Too late. I was forgetting that when I hit start my Tahoe will take over and crank it until it starts. Which it did almost immediately. In a panic I glanced at the oil pressure and I had 60 psi. The most the 5.3 had been managing was 40 on the highway turning some revs.

I had a pretty bad exhaust leak where the right manifold connects to the exhaust. I only had 5 of the nuts for those studs and what I thought was going onto the odd one was the wrong thread and had stopped while I tightened the other two. I found a correct nut and backed things loose and drew it up evenly for a snug fit.

At this point I'm trying to figure out why it started and ran for a few minutes then cut off. My guess is it's to do with the partial programming I got done and some signal the computer isn't seeing. Of course I got backed out of my nice warm garage into the cold rain when it quit.

That run showed me the exhaust leak and knew I had some crawling to do. It took 45 minutes but I managed to get it pushed back in up a slight grade by myself. Then I fixed the exhaust.

While I was doing that I kept getting dripped on from a coolant leak somewhere around the back of the right head. Gotta figure out where it's from.

Eh, I'm sure it's fine. Aside from the exhaust leak, how'd it sound upon firing up?

 

[PatDTN]

Sounds strong but...

I looked at the codes and it says crankshaft sensor variation not learned.

With the exhaust fixed it's nice and quiet. I got it to start again after fixing the exhaust and thought maybe the right side o2 sensors caused a problem causing the computer to shut it down. I decided to pull it out again. Shut down and the battery's dying so I dragged an extension cord and charger out to refresh it.

 

[kbuskill]

Sounds strong but...

I looked at the codes and it says crankshaft sensor variation not learned.

With the exhaust fixed it's nice and quiet. I got it to start again after fixing the exhaust and thought maybe the right side o2 sensors caused a problem causing the computer to shut it down. I decided to pull it out again. Shut down and the battery's dying so I dragged an extension cord and charger out to refresh it.

A crankshaft position relearn is very common when you reflash an ECM. The Tech 2 will tell you that when you reflash the software on the ECM.

Do you have a Tech 2?

If so it's pretty easy. You just go into the menu to relearn the Crank position and then rev the engine up to like 4k rpm or something like that.

 

[PatDTN]

Yeah, no tech2. I'll get AAA to tow it to the shop that did the preliminary tune.

I'm more concerned about the coolant drip. I wonder if I heated the plug at the back of the head when I was removing the broken exhaust manifold bolt. I know there's a warning about voiding the warranty if that plug is melted. I didn't examine it closely either before or after removing the bolt.

 

[Geotrash]

Yeah, no tech2. I'll get AAA to tow it to the shop that did the preliminary tune.

I'm more concerned about the coolant drip. I wonder if I heated the plug at the back of the head when I was removing the broken exhaust manifold bolt. I know there's a warning about voiding the warranty if that plug is melted. I didn't examine it closely either before or after removing the bolt.

You mean this one?

 

[iamdub]

I'm more concerned about the coolant drip. I wonder if I heated the plug at the back of the head when I was removing the broken exhaust manifold bolt. I know there's a warning about voiding the warranty if that plug is melted. I didn't examine it closely either before or after removing the bolt.

The parts yard probably glued a heat tab to the freeze plug. The center of the tab is designed to melt at a certain temperature. If that center of the disc (looks like the back end of a bullet) is missing and/or molten, they'll know the engine was overheated and won't warranty it. The tab itself isn't sealing the coolant jacket, though.

I doubt you got that area so hot that the head warped enough to spring a leak at the freeze plug. I'd double-check the coolant block-off. Did you use new O-rings on them?

 

[kbuskill]

Are you sure it is leaking from the engine and not the plastic T-connectors on the passenger side of the firewall?

 

[PatDTN]

Are you sure it is leaking from the engine and not the plastic T-connectors on the passenger side of the firewall?

T-connectors? I had the stud on the end of the coil pack hook up a couple of places pulling the engine. You might be onto the issue. It's dripping down across the end of the exhaust manifold so it's kinda far back for the engine. More inspection to come.

Thanks all y'all for great ideas. Seriously I doubt I could have pulled this off without the forum.