2000 Blazer running bad when cold

[friesza]

So how many O2 sensors are there on a 2000 blazer 4.3 4wd? My next maitenance is this....and I have had the same problem with my blazer and it seems to happen this time of year when it gets wet out...so it lead me to replace cap and rotor and it got better.

[old_master]

There are 3 sensors on a 2000 4.3L engine: One close to each exhaust manifold, and one just downstream of the converter. Keep in mind that O2 sensors are ignored by the ECM until they are warmed up, (approximately 3 minutes on a stone cold engine). If the engine misfires during warm up, it's not an O2 sensor causing it. What brand distributor cap and rotor did you use? Did you put a dab of silicone dielectric grease on each terminal, (inside and out) of the cap when you installed it? Is the SES light on, or does it blink on acelleration?

[friesza]

Originally Posted by old_master

There are 3 sensors on a 2000 4.3L engine: One close to each exhaust manifold, and one just downstream of the converter. Keep in mind that O2 sensors are ignored by the ECM until they are warmed up, (approximately 3 minutes on a stone cold engine). If the engine misfires during warm up, it's not an O2 sensor causing it. What brand distributor cap and rotor did you use? Did you put a dab of silicone dielectric grease on each terminal, (inside and out) of the cap when you installed it? Is the SES light on, or does it blink on acelleration?

I was just wanting to know how many to buy...I figured out the stumbling prob last year....just can't do any work on it for a week or two as I just had abdominal surgery and cannot lean or crawl so I couldnt check to see how many I needed...but great info anyway...thanks

[old_master]

Bosch part #15703 for the direct fit sensors, they're about $50.00 each. Don't waste your time or money on the universal fit sensors. Might need to use a little heat to get the old ones out... drive it until it reaches operating temp then remove them, they'll come right out. Invest in an oxygen sensor socket if you don't already have one, http://www.harborfreight.com/3-8-eig...ket-95045.html