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Question on 99 4.3 Vortec , swaped engines both 4.3 but one was CPI, the one put in is CSFI, both out of 99 s-10, would I need CSFI PCM are they different? The truck has no power and fuel trims are -25 at higher rpm. Droped exhaust no difference, maf was clean and tested ok, un plugged maf no change. O2s are switching, fuel trims at idle are 2-5, map checked out ok. Engine ran fine before pulled. I know I am asking a lot but any help would be greatly apricated Thank you
US market?
I thought that the 4.3 vortec only came with the CSFI "spider injector". For the 99 model year s10 anyway...
In either case, I don't think the CFI (with two injectors), would have the drivers necessary to fire six injectors.
I'm honestly surprised it runs.