2014 chevy 2500 express 6.0 CNG to Gasolina

[Jak Stoll]

Hey folks I am new to this forum and new to HP tuners. I had a customer call me this morning with a 2014 Chevy Express van. Apparently they have replaced everything and the vehicle starts and runs after a conversion from CNG to gasoline. He has some minor driveability issues says it needs to be cranked a couple of times to start and that there's a delay in the throttle if the vehicles moving from 0 speed but if the vehicle is moving the throttle response is normal .... He says he replaced the ECU and that the new ECU does the same thing. And that a dealer technician was unable to perform programming to correct the problem... So I'm wondering if I can help him with HP tuners? Also wondering if any of this sounds familiar to any of you? Thank you for taking the time to read this I hope you can be of help :-)

[TheMechanic]

Yes, familiar. Attempted the same on an earlier vehicle. DID NOT WORK. It is hard wired to a separate module that is expecting certain parameters to match on the CNG tank. I was going to try and make a few voltage dividers to mimic minimum settings but customer didn't want to spend the time=money. The long crank time is from the system attempting to try CNG first then switching to gas. Like I said sever voltage dividers and I think I could have tricked it. Honestly the best bet would be a complete harness and ECM/TCM swap to a totally different VIN.