QuestionQUESTION: I have a 1999 chevy blazer 4wd 4.3l 6-cylinder. When I first start the engine my rpm reads 900. As the engine gets warmer, the rpm drops down to normal idle speed. Why is this?
ANSWER: HI CHRISTOPHER, THIS IS NORMAL,WHEN THE ENGINE IS COLD THE COMPUTER WILL RAISE THE IDLE SO IT WILL NOT STALL OUT..IT PUTS MORE FUEL IN THE ENG BY ALLOWING THE INJECTOR PULSE TO STAY OPEN LONGER AND AT THE SAME TIME RAISES THE IDLE.. BEFORE FUEL INJECTION WE HAD CHOKES,THIS WOULD ALSO RAISE THE IDLE UNTILL THE OWNER HIT THE GAS AFTER IT WARMED UP AND THIS REMOVED THE CHOKE DROPPING THE IDLE....YOU SEE IF YOU START A COLD ENGINE UP AND THE IDLE IS NOT RAISED UP IT WILL STALL UNTILL IT GETS WARMED UP..THIS IS A GOOD FEATURE.. HOPE THIS HELPS YOU ,,TOM...
SORRY I FORGOT TO ASK YOU WHAT EVER HAPPENED WITH THE TRANSMISSION PROBLEM ????
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QUESTION: I have a 1999 Chevrolet blazer 4wd 4.3l 6-cylinder engine with code Po452 that was scanned by Autozone. It reads fuel pressure sensor low input, check connector and wiring and hose and fittings. The question is where is this sensor located and how to fix it?
AnswerHI CHRISTOPHER, THIS SENSOR IS ON TOP OF YOUR FUEL TANK. THE TANK WILL NEED TO COME DOWN TO GET AT THIS SENSOR...THEY DO GO BAD. CK THE WIRING TO THIS SENSOR ON TOP OF THE TANK AS WELL. I HAVE FOUND SOME CORRODED WIRING HARNESSES THERE AS WELL. GOOD LUCK TO YOU,,,TOM.....
