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Everything posted by TJay74

  1. And hence how outdated info and testing from "decades" ago is when it relates to much more modern engines and ECM's. A LTx engine wont make more power at 230° of coolant temps, it will make less power due to the heat. The coolant temps alone will have the ECM pulling timing, couple that with it increasing the IAT temps and them pulling timing as well. GM's Ltx engines already struggle to not detonate on 91, adding heat to them in the form of coolant temps and intake air temps will only cause the issue to be worse as the temps go up.
  2. The dealer is about the only to program a BCM for you, with that they are vin tied to your vin for the firmware. You wont be able to add on any other features or options other than what your truck came with from the factory.
  3. Intake manifold has to come off to replace the HPFP, with that it only takes maybe an hour to replace it. You will need the high pressure pipe and the high pressure cross over pipe and of course the pump. The intake manifold gaskets are reusable, but they also arent that expensive to replace either.
  4. the OEM cats are covered 8yrs/100k per Federal Mandate. Also a P0420/0430 can mean a clogged cat, a clogged cat can get really hot and possibly start a fire. No matter if they are inspecting or not where you live, it get the issue fixed (replace the offending cat) or delete the cat (harder to do now since HP Tuners doesnt offer the ability to delete cat codes anymore).
  5. You cant use the BCM from the donor truck at all, the modules are all VIN tied to the vehicle now. Cant swap them and cant program them to work either. If this mod requires the BCM (It does) you will be hosed and stuck with a fancy tailgate that doesnt work.
  6. Not much a person can do if they need a truck right now. Used pricing is almost near what the new price of the vehicle was and new vehicles are short on the lot so the ball is in the dealer hands on both sides, gonna stay that way for the next year or 2 unless the pandemic ends and things go back to "normal". I bought my 2016 Sierra CC 4x4 SLT All Terrain 6.2/A8 in March of 2016, at the time with my discount and the rebates a $56k truck ended up being $44k. Truck now has 46k miles on it and is in amazing condition, I went to see what it is worth and I can sell it private party for $40k right now, if a dealer tries to sell it the price is $44k to $47k on a dealer lot. So heck yeah, I am jumping on that deal. Gonna sell the truck in February or March and order a BMW SUV for the wife at MSRP and take the money and run. I tried to look at a 2022 All Terrain Carbon edition, $66k price tag and the dealer wants a $5k ADM! After this move to BMW for us we will only have my 19 Corvette Z06 left in our garage as a GM vehicle, the others are a 18 Audi S5, a 19 Audi S4 and then the new 2022 BMW X3 M40i.
  7. P0430 is because the post cat O2 sensor is saying the ECM doesnt think the catalytic convertor is doing its job. Either gonna be a bad cat (under warranty for 8yrs or 80k miles per Federal requirement) or a bad downstream O2 sensor or a bad harness to the downstream O2 sensor.
  8. Until you pull the code you are just throwing guesses into the wind. As long as the CEL is stored in the ECM and the issue is not fixed and the ECM self-clears the code the remote start wont work. If you clear the CEL all it is gonna do is work for a bit, then once the CEL triggers again it will lock out the remote start. Start with the basics, get the truck scanned and get the code then go from there.
  9. Correct, and as long as the fluid meets or exceeds the vehicle manufactures specs you are free to use what ever fluid you want in the vehicle.
  10. I am guessing this is a new change for the 2019+ trucks then, we all went round and round with this on the K2xx trucks with the GM and the dealers. So my apologies to that and kudos to GM for allowing known tire sizes to be calibrated for in the modules. The newer lane avoidance, advanced cruise control and collision cameras all add some complexity in allowing the vehicle to drive correctly. We also have a 2019 Audi S4 and it is the same way with Audi, everything has to be correct otherwise some of the systems wont work correctly.
  11. Ethanol is a cheap and amazing way to get rid of knock. My 2016 6.2/A8 has been on E85 for 4 years now, it runs great. Even still if a person only has 91 they can add up to E10 with no harm. If the trucks tank is 26 gallons that means you can easily add 2.5-3 gallons of E85 to the 91, it will help with detonation and make the truck run better as well.
  12. This was a very basic run down, once you get into oxygenated fuels you get into a whole new type of conversation.
  13. Dealerships are not required to sell a vehicle at the GM Employee price, so yes the ADM could be something you pay if the dealer is not willing to sell the vehicle at the GM-Employee price.
  14. You need to be very careful tapping into just any 12v source, "noise" on those 12v circuits can affect the CANBUS data system and causes issues with modules on those systems. This has been a problem since the more complex CANBUS stuff started launching in 2010+. The new C8 Corvette is running into this issue now, guys are putting dash cams and radar detectors in the C8's and tapping into the rearview mirror circuits, the noise from that is back feeding into the circuit for the outside power mirrors and causing the mirror glass to spiderweb out. GM has finally found the issue and issued a TSB on it to deny coverage if a radar detector or dash cam is found in use.
  15. No they cant, GM hasnt allowed a reprogram of the BCM since the K2xx (2014+) trucks launched. Doesnt matter if it is a factory size or not, GM TAC has refused those requests for years now hence why people went after the Hypertech programmer to calibrate for tire sizes. 275/60-20 is 32.99" overall height 265/60-20 is 32.52" overall height 275/65-18 is 32.07" overall height Without looking into the ECM/TCM to see the number GM used, in the past the Rev's per mile that GM used for the speedo were the same for all 3 of the tire sizes GM used on the 1500 series trucks.
  16. To reinforce what RCF71 just said: Lower octane fuel burns faster, but doesnt produce more BTU's (energy) than higher octane fuel. The speed of the burn from the octane is what can cause the issue when used in a engine that has a high compression ration. The sound of detonation or knock is caused when pre-ignition happens. As the fuel-air mix is pushed into the combustion chamber and is compressed the leading edges of the valve or the valve reliefs on the pistons can be hot enough they ignite the fuel-air mix before the top of the compression cycle and before the spark plug actually fires to ignite the fuel-air mix. This causes an issue due to when the hot spot in the chamber ignites the fuel-air mix it starts a flame front (propagation) to race across the combustion chamber. As the flame front is racing across the chamber the spark plug then ignites the mix as well, now you have 2 different flame fronts traveling across the chamber towards each other at the speed of sound. When they collide the cause the audible "knock" or pinging that we hear. This also can cause damage of the knock is severe enough, when inspected the tops of the pistons will have marks on them similar to if you hit the piston top with a ball peen hammer. The way you control this is with a higher octane fuel that burns slower and resists pre-ignition, this allows the spark plug to do its job and to ignite the fuel-air mix with a single spark source.
  17. I doubt GM has changed how they did this on the K2xx trucks, typically the overall tire height for the 18" and the 20" are exactly the same, they use the same Rev's per mile in the ECM. You shouldnt need to change a thing as long as you are using the same tire size as the stock 20" tires.
  18. There is no 5v power in the vehicle you can tap into, 5v is a reference voltage that the engine sensors use. If you have a 12v/5v inverter it sounds like you are looking for a 12v source, yes?
  19. You are not going to be able to use the ECM or TCM from the 6.2 setup, you will need to plug your ECM/TCM into the harness and then have your tuner update the tune in each module. The 6.2 ECM/TCM is VIN encoded and TIED to the VIN it was assembled for and that was flashed into them. The only way around this would be to find someone that can reprogram and flash the ECM/TCM with a VIN change, that will just add more costs and complexity to your swap.
  20. No the gain also comes from the timing increase, depending on the composition of the E85 you are gaining anywhere from 2°-5° of timing all through the map. On my 16 Sieera 6.2 I data logged it from new to now. Even on 91 the gas timing tables are very aggressive and the truck would show knock all times of the year, was much worse during the summer months. Even with 93 in the tank the knock was still present. I spent some time cleaning up the main gas timing tables to try and reduce the knock while on 91/93. The moment I put E85 into the tank as soon as the E85 gets over E40 any occurances of knock go away, my truck sits around E70 to E80 year round. I dont ever see knock while I am on E85 whereas if I am on gas even with reduced timing in the main gas timing tables I see tip in knock and burst knock at times even with me reducing the tables some.
  21. E40 -50 doesnt produce max timing, the ECM use a ethanol scaler table in order to determine how much percentage of timing the ECM sees as an adder from the main flex fuel timing table. The scaler starts at 0% then 10% then 20% then 50% then 80% of E85. At 50% (E50) the scaler table is using a modifier of .5 which means if the Flex fuel timing table is offering say 4° of additional timing and the ECM is seeing E40-50 the main timing table is only getting an additional 2° of timing for the E85 fuel. All of those works on a variable sliding scale depending where at on the modifier table the composition is at. Also not "all fuel in the USA has E10" in it. I live in OKC, we still have 100% gas. It depends on the station and what fuel rack they get their fuel from. I still see E0 at times when I have ran 100%, just like our E85 here is around E80 in the summer months and E60-E70 in the winter months depending on the gas station. We do have a gas station that keeps race fuels on their pumps, their E85 hits dang near at E85 and they sell E100 as well that is spot on. The problem is N/A just wont see the gains from E85 as say a forced induction engine. My 16 Sierra 6.2 and my 2017 Camaro SS 1LE both saw gains of around 25-30 at the wheels on E60. My 19 Corvette Z06 picked up 70rwhp on E60 over the gas tune. My 16 Sierra 6.2 sits around E70-E80 year round, my data logs confirm it sees more timing advance on E75 than it does on E50.
  22. While the physical swap is plug and play, you will need to update the tune in the ECM from the 5.3 to the calibration from the 6.2, so tuning will be required for this swap to work. For the person who said why dont you swap a diesel into the truck, that wont be possible without a major overhaul and a complete new wiring harness and custom modules as the gas ECM is not setup for controlling a diesel. The L86 physically is the same engine as the LT1. The block, pistons, rods, crank, cam and heads are exactly the same. The LT1 uses a different intake manifold and different exhaust manifolds and as said different tuning. The high plenum of the L86 will allow it to produce a better torque response over the LT1 intake manifold. If it was me I would swap all of the fuel system as well, the LPFP, the HPFP and the injectors over the L86 stuff and then add in a ethanol sensor and tune the truck for E85 flex fuel as well. I own a factory L86 truck setup on E85 and runs solid for a 4x4 truck.
  23. You would need to be using HP Tuners using the scanner app and log all of the timing modifier tables to be able to see what your actual timing is. I have about 8 or so timing channels I log to see what is actually impacting timing. With that E85 has a octane rating of around 105 octane, E85 also imparts a cooling effect on the combustion process and keeps the combustion chamber cooler which allows more timing to be added. While E85 does require more fuel, it isnt anywhere near the 30% or 40% I see people quote as it depends on the EQ Ratio that is being commanded and if it is part throttle or WOT. There is no reason to run E30-E40, if you have the ethanol sensor installed and the tune is setup correctly you can run E85 at full strength (what ever your local pumps are, mine in OKC are anywhere from E60-E75 in the winter and E75-E80 in the summer) with zero issues. Only running E30-E40 is only going to give you maybe an additional 1° of timing advance.
  24. P050D is the code that triggers when an injector is failing during cold start. There is a service process to determine which injector it is that is failing. The increase in oil pressure is part of the reduced power mode as part of the fail safe for the engine. If swapping the plug, coil and coil wire didnt change the position it leaves either the injector is failing or the AFM lifter has failed on that cylinder. While the injector is not hard to R&R it does require pulling the intake manifold and the injector rail. Per the service manual you will need both of the hard fuel pipes to be replaced as they are listed as 1-time use, I have reused them in the past with no issues as well. If you buy a new GM injector you will need the injector info printed on the injector to determine which injector you need as at one time there were 3 or 4 injectors to chose. The brand new injector comes with the teflon seals already installed.
  25. I am glad someone point out, there are more than just the 2 timing tables used when on E85. You have the high/low table for gas, the high/low table for gas when DOD is active, you have the main adder table for E85 and then the modifier table for the composition of E85 that the ECM is seeing from the Ethanol sensor. The E85 main table adds to the main gas table and then based on the E85 percentage composition reported then uses the modifier to determine how much of the E85 main timing added is used. So if the E85 main timing table is calling for an additional 5° of timing and the Ethanol sensor is reporting E70 then the composition modifier table references the percentage of timing adder allowed (say 50% for this example, but it is a sliding scale) and adds 2.5° of additional timing to the main timing table for gas. You can log all of the timing PID's in the HP Tuners scanner app and see exactly where the ECM is adding or subtracting timing from at any time.
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