Have an 88s10 with the 2.5 and 5 speed that will almost always stall out when slowing down or downshifting gears, always starts right back up . The injector above the throttle body is flooding the TB with way to much fuel and causing the truck to emit real thick grayish colored smoke out the exhaust pipe with the smell of unburnt fuel and a small pile of liquid forming around the end of the tailpipe . Have changed out everything but the TPS. Wondering if it’s that or something along the lines of the o rings on the injector are bad or something. Any help or advice greatly appreciated