2000 blazer wont start without starting fluid. has had tune up with cap n rotor. new fuel filter my question is.... could it be O2 sensor?? the reason i ask is back several months ago i gutted both converters due to lack of $$. theyre expensive. its thrown the O2 code since then but hadnt had any problems running or starting bfore now. COULD this b something to look at??

 

If it starts with starting fluid you more than likely have a fuel problem. You need to check you fuel pressure at the test port and do a leak down test. Key on engine off pressure should be 65 psi. Key off pressure should hold without leaking down. Fuel Pump, Clogged fuel Filter, leaking regulator, Stuck poppets. Are all possibilities.

 

was just a thought. had fuel pressure tested but wasnt sure of specs n now i dont remember but do remember it was around 55?? but not sure if that was idling?? didnt do leak down test though but surely will thanks

 

You dont test the fuel pressure with the engine running, Test it with the key in the on position, but engine off.

 

head down to the auto store. autozone,oriellys etc lends out fuel test units. Some of them wont charge you a retail deposit (100% refundable) if you test it in the parking lot. try to go somewhere close. fuel results when engines been hot for a while isnt as accurate.

fuel pressure MUST ping at 58-60+ at key on. and hold above 55ish for 10 min.

Incase you ask where you test it. Behind the engine,driver side. you'll see a nipple with a black cap. the tester screws onto it.

 

i wrk nights but will definately test n mornin. thanks

 

Just FYI - those post cat sensors do absolutely ZERO for how the engine runs. Their sole purpose is to tell the computer if the cats are working as designed - nothing more.

If they're not working (as yours aren't, because they're not there) it throws a light with the code P0420 - catalyst system efficiency below threshold. The engine's control of fuel and spark will not change whatsoever. It's just there to keep the EPA & treehuggers happy by throwing a light/code so you fail inspection in areas that test for such things. They get your money for the test, and your forced to spend your hard earned money on a VERY expensive cat, and the state gets more tax revenue on the repair and on the part. It's a win-win for everyone ... EXCEPT US! Just another way to get you to part with your cash ...

 

Moved To: 2nd Gen S-series (1995-2005) Tech

 

update...fuel pressure test was ok but failed the leak down test. gonna put in fuel pump and hope for the best. ill update again. thanks for everyones insight.

 

I hope you go oem on the pump.