Hello,i recently went back to a stock ecu from a holley unit. i had sold all my hp stuff an deleted most the cars old files. but had found one semi tune that i had from before. i had modded it some from what i new the car liked when on holley for timing and ve idle area. i was just going to drive and log the afr an make corrections to the ve that way. i took that tune and used a mpvi2 an loaded it up. when i went to start the car it didnt want to an backfired threw the exhaust,which i thought was extremely odd.( side note, the stock ecu harness remained stock when i ran the holley.the stock ecu an holley just shared the crank signal and the tps signal. this was so the factory gauges,fuel pump worked along with the stock ecu still working the 4l60e via it seeing the tps and crank signal. i had made splitters for this so i could keep the stock harnesses of each intact. the splitters have been removed and everything is plugged up how it was via factory}
once it did the backfire i went back to that semi tune and stuck the timing tables i had in it from before so basically 24* at idle vs on holley it liked 30ish an left the ve basically the same(just blended it more). i load that tune into it an it starts but runs oddly almost like its misssing or on bad gas now. i think hmm maybe its just hp tuners an then go to reload the tune. now the car wont start an acts like it wants to backfire again. im like wth an go to then reload it and at this point it will not connect to the ecu now. so im pretty sure it bricked the ecu on me. which blows, but my main concern an wonder is if its the mpvi2 doing it or maybe something in my tune. the battery voltage was good at the time so i dont think it was that.
cars background is a 99 z28 cam an bolt on deal. has a custom 243/251 112+2 dur cam with 21 degrees of overlap,sheet metal intake with 102mm tb,gtp white injectors( the correct data is in the tune) 4" cold air pipe feeding the 102mm tb. no maf an is setup for olsd at the moment. compressions right around 10.25-1 an has a high stall.headers,x pipe an bullets for exhaust (the basics). heres the tune i was trying not sure if someone wants to peak at it an see if they see anything that might jump out. car idles in the mid 70s kpa,the base idle airflow should be correct or close. its what worked on the car before i went to holley and the only change is the sheetmetal intake with a 102mm vs before was a ported/worked ls6 with a 92mm on it.
well the ecu connected today for me so thats a plus,only thing i hadnt done the other day was reboot my laptop. Now the crap part is the car still wont fire and sounds like its 180 out some how. i used the tunes i had,the semi tuned one an another i remembered i had from my first olsd tune in emails. the car had started on 3 of them being recent when it acted like it had a miss or from before. none would get the car to fire now.it would just backfire out the exhaust.
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