Backfire between shifts/ HPT
#1
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2 different cars, same mods (just bolt ons and headers/ exhaust) I tuned both of them from VE to MAF, PE and then timing. I kicked them to OLSD, tuned the VE via wideband, enabled the MAF and tuned it via wideband, put all back to CL. All was fine during tuning and was great after I drove them, but now they tell me that between shifts the car will backfire. Why, I have no idea? The only thing I can think of is in some of the VE cells (4800+ at 15-20 kps), the VE changed up to 20%, but that shouldnt matter since the PCM is 100% MAF after 4k, or does that change when the TPS goes to 0% between shifts? Im not new to VE tuning as I tuned my 2 bar CLSD turbo car from scratch.
I would post the HPT file, but my laptop had HD failure
Any ideas to check?
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I would post the HPT file, but my laptop had HD failure
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