5.3 Base Tune Help

**Acamp2469** · 09-04-2024

OS : P01_12212156 Current Tune : 2002 Chevrolet Silverado Truck Manual LM7 5.3 Litre (12212156) from a tune repository i found via googling and this forum. Ive been having issues with a 5.3 LS Swap with a 700R4 behind it. My current setup is a junkyard swap 5.3 with a LS1 intake instead of the truck intake. Ive been able to get it to start and idle enough to know the engine runs however it does not like throttle at all and is very touchy. I took the base tune above and adjusted the VE and MAF a little and that somehow got it starting/idle when it gets warmed up. I still have to crack the throttle a little to get it to fire up easily. Under throttle it just dies and i feel its going lean. The odd part to me is this motor to my knowledge from a junkyard is all stock other than the LS1 intake with a stock throttlebody but it would not start with just a base tune. I did swap the OS to the one above on my PCM and it definitely got better. We have been thinking is it possible this thing has a mild cam in it causing issues with a base tune working? We've taken the valve covers off and the valve train all looks stock so if it does have a cam its nothing crazy. Im in need of some help finding a good base bin tune to get it running fully so i can drive it on the street to a tuner to get it dyno tuned. If anyone knows where i can find a good tune for this combo that would be much appreciated. My tuning knowledge is very lacking but with some guidance maybe i can get this thing running i just am very unaware of what tables to adjust. Thanks in advance.

**MO LS Noobie** · 09-04-2024

Some PCMs do not have the drivers for idle air control, so is this a DBW "drive-by wire" or DBC "drive by cable" set up?If you feel that it is a lack of fuel you can take a propane torch and feed a little bit of propane into the throttlebody and see if that helps it idle correctly.Always a chance that the injectors are plugged up with a junkyard engine.Are you trying to get it to run without an intake to and/or mass airflow hooked up?There are places on this site to tell you what hardware number is equipped with the drivers for the various systems.I hope this helps. If these don't lead to a solution if you post your hardware number and your current BIN we could look at it and see if there's something obvious, because there's the chance it is a modified BIN.

**2xls1** · 09-05-2024

All the P01 PCMs have IAC drivers. It is the P59 blue/green PCMs that were used on so many DBW vehicles that might not have them. OP what injectors are you using with that LS1 intake manifold? LS1 or 5.3?

**Acamp2469** · 09-05-2024

Thanks for the replies guys. So its DBC injectors were tested/cleaned one by one before installing them with new Holley fuel rails. We are using the original 5.3 injectors but we took the cap guide off and installed them in the LS1 manifold with some spacers so they are properly installed. Attached is the base tune i started with and the modified version i got working (which is prob not a good tune but it got me idling good enough to do a heat cycle). OS for the tunes is P01_512Kb : 12212156. We are running with all sensors including MAF/O2s/IAT etc. it doesnt seem to like to start without the MAF hooked up.