NON-VVT L92, First Drive, Ran Hot

[7.5in.300BLK]

Good Morning. I finally got the engine in and on the road for the first drive today... Unfortunately the first drive was on the interstate for the 30 mins it takes me to get home from the shop I did the work.

Now I am going to get real with you all, I am a UTI graduate, I was awarded Student of the Course for 2 of the 3 power and performance classes, and I tuned the "Fuel Map" on a 2006 Corvette... in 2014... So when it came down time for me to make a decision to either replace the engine in my Wife's Yukon or the just replace the Yukon, I said, "Who can afford a used car in today's market and, really, how hard could that be?" This isn't my first engine build, but it is my first LS. I feel like I have a pretty decent understanding of what makes an EFI vehicle run, and when I bought my MPVI3 I thought, "How hard could this be?" Ok, here's the slice of humble pie... there are A LOT more settings and parameters in this software than I remember, and, I will admit, I am a little overwhelmed.

All that being said, I could use some help, some being a lot. I would love to post the log of my first drive, but it was 1:30 am when I left the shop and, well, my computer's battery died on the way home. I do not know how to do dongle logging with my phone yet, and, quite frankly, I don't even know what parameters to set in the scanner to make this optimal and efficient. Sure, I could go onto YouTube and watch tutorials, but that already kind of put me in a pickle. My wife had to dig me out by posting here on my behalf. I will post my current tune though, feel free to take a gander and rip it apart if you'd like. Before you pull out the daggers of hate let me say it first, "I have no idea what I am doing." There, I said it so you don't have to. I have to take the truck to another shop to charge the AC after I get a few hours of sleep, I will post a log after that. I am thinking tomorrow I might be able to dedicate a few hours to tuning. Also, If anyone has any links to a good TCC Disable tutorial thread, that would be great.

Thanks in advance.

Step 3 - Base Tune 1.hpt

[gtstorey]

Start with the running hot. Probably not a tune issue. Probably gas an air pocket in the cooling system. Or a wiring issue on the fans although they probably shouldn't have been needed on the interstate.

[gtstorey]

And stop with the starting new threads for every different issue.

[7.5in.300BLK]

Thank you. I'm burping it again before taking it out for another drive.

[7.5in.300BLK]

Now it's showing Bank 2 going lean and multiple cylinder misfire. I'm going to go ahead and post the recent files:

[7.5in.300BLK]

Here is an updated file

[7.5in.300BLK]

The misfires stopped when the coolant reached 150. I burped it 4 times yesterday. The last one was with the nose two feet in the air. The first fan kicks on low at around 200 degrees. I agree that should be irrelevant on the interstate.

[gtstorey]

what was in the truck before the engine swap?

[7.5in.300BLK]

what was in the truck before the engine swap?

It was a stock Yukon XL Denali with a stock 6.2 L92 with a VVT Cam

[gtstorey]

And what is in there now?

[edcmat-l1]

You shouldn't have to raise the front of the truck. There are other, simpler ways to get the air out. In stock form, it's pretty damn easy.

[7.5in.300BLK]

And what is in there now?

It's a stock L92 (freshly rebuilt) with a Summit Racing towing cam

Here's what I installed new: stock crank, stock pistons, Hastings rings, BTR Springs, BTR Trunnion Upgrade, BTR push rods, Earl Steam Vent Kit, Throttle Body, Melling High Volume Oil Pump, ACDELCO 2173347 Injectors, MSD Blaster Coils with coil pack wiring harness, Summit Pro LS Camshaft and Lifter kits (SUM-K8718R1), Summit VVT Delete kit, and replaced all sensors with GM genuine.

[7.5in.300BLK]

At this point, I'm pretty sure all the air is out. It's still over-heating. That's why I'm wondering if it isn't a timing issue.

[Cringer]

I see two logs. One shows ECT at 102*F and the other at 111*F, so I am not seeing overheating. Do you have cats? Your idle timing is floating around 0* so that is one source of heat that needs to be solved.

How are you determining misfires? Since you have replaced the stock cam with an aftermarket towing cam, the ECM's misfire detection is not calibrated properly and reporting false misfires (I mean, there may be real misfires, but we can't determine that yet). I do not see O2 sensor voltages in the logs so a real human determination of misfires cannot be determined.

[7.5in.300BLK]

I see two logs. One shows ECT at 102*F and the other at 111*F, so I am not seeing overheating. Do you have cats? Your idle timing is floating around 0* so that is one source of heat that needs to be solved.

How are you determining misfires? Since you have replaced the stock cam with an aftermarket towing cam, the ECM's misfire detection is not calibrated properly and reporting false misfires (I mean, there may be real misfires, but we can't determine that yet). I do not see O2 sensor voltages in the logs so a real human determination of misfires cannot be determined.

Thank you, this is all super helpful. I shut off cylinders 2, 4, 5, and 7 and there was no response from the engine. When I turned off 1, 3, 6, or 8 it lugged and almost stalled. I had all four cylinders shut off at the same time. This is seems to be an issue with a cold start when I start it in the AM. They seem to shut off until the engine reaches 150 degrees. Unfortunately, my computer died during my last drive. But it reached 225 degrees at 65mph at a slight incline. I honestly feel like I may need help with timing. I burped the system, ran it, burped it again. When I burped it this AM I didn't get any bubbles so I'm assuming I have it all out. I have an Earl's Steam Vent kit. I'm just not sure where to go from here. My computer didn't save the last log correctly so I can't upload it. The ECM is using the spark tables for a VVT L92 and I feel like the majority of the issue is in the timing not the cooling system?

[DanN]

At this point, I'm pretty sure all the air is out. It's still over-heating. That's why I'm wondering if it isn't a timing issue.

When I picked up my LS to rebuild, there were clear signs it had been pretty hot. It turned out the RH head gasket had been installed upside down, and I think that was the cause of the overheating.

Most head gaskets will have a tab along one side that sticks out from under the head on the outboard side; I believe they should be in the same position left and right - check the brand you bought to be sure.

[Cringer]

Thank you, this is all super helpful. I shut off cylinders 2, 4, 5, and 7 and there was no response from the engine. When I turned off 1, 3, 6, or 8 it lugged and almost stalled. I had all four cylinders shut off at the same time. This is seems to be an issue with a cold start when I start it in the AM. They seem to shut off until the engine reaches 150 degrees. Unfortunately, my computer died during my last drive. But it reached 225 degrees at 65mph at a slight incline. I honestly feel like I may need help with timing. I burped the system, ran it, burped it again. When I burped it this AM I didn't get any bubbles so I'm assuming I have it all out. I have an Earl's Steam Vent kit. I'm just not sure where to go from here. My computer didn't save the last log correctly so I can't upload it. The ECM is using the spark tables for a VVT L92 and I feel like the majority of the issue is in the timing not the cooling system?

Update: I think I had a problem on my end, I see O2 voltages in the log. B2 looks totally dead. Check for spark and fuel.

The first issue you should be solving is no fire on those B2 cylinders IMHO. You can spit on the headers or spray water on them to find the dead ones.

Did you replace the thermostat? Are you sure the water pump is good and actually moving water?
Do you have cats?

Attached is a tune that disables misfire detection. The ECM freaks out when it thinks there is a misfire, so this will help to eliminate some of the noise. Use this going forward.

Step 3 - Base Tune 1 (1) - misfire disabled.hpt

[7.5in.300BLK]

Thank you! The dead cylinders only happen before 150. The thermostat is brand new Gates 187 degree. The water pump is brand new AC Delco. No cats

[Tech1340]

Did you check all the grounds? You have 1 on the front of the passenger head with 2 wires, one on the back of the drivers head and 2 wires on the block behind the PS pump.

[Cringer]

No cats

In that case use this file as your base going forward. Some changes you can see...and some you can't due to newer HPT versions removing some options.

Step 3 - Base Tune 1 (1) - cat stuff.hpt