I was trying to tune a 2003 Silverado LQ9 swap: LQ9, 212/218 TSP, 799 heads, LT headers 81.L injectors (aftermarket Radio subs)
I was trying to tune this truck, I get to it and write the PCM 2-3 different times w/fueling changes, spark, and varies other changes, and a new OS for RTT (which the RTT didn't work). I get to the end of the street to make a change and nothing. write timed out no crank nothing! Tow it back and put a charge on it and writes fine. I left and issue occurred again. Next day bought a new battery and wrote only with a charge on it (2amp). This worked a handful of times and the issue came back had to disconnect everything touch the battery cables and it worked for 1-2 writes and then timed out. Eventually that stopped working all together removed subs and Radio Fuse still no luck. After re-syncing my MPVI2 the PCM would write flawless or so I thought. I go to write the PCM, it loaded and now just Cranks and cranks and nothing. It read RPM during cranking I didn't save the scan file for cranking no start. I up loaded the last file that I was using and it didn't work. Go back to the file before that and it still wouldn't fire off. So I just started over with a base file and only made start up changes with no effect. Could someone look at this and tell me if its the files or another issue? This is an absolute ball buster as I drove an hr to help a friend w/a truck that would start messed with it for two and half days but ended up leaving with a truck not starting (just my luck).
'03_Silverado_Base_changes_Current_File.hpt