I have a 1991 S10 Blazer that failed emissions.

what about the o2 sensor?? that is a very important for the hc and co.

is the motor working on all 6 cylinders??

Roy

I was told the o2 sensor tested ok. As far as I can tell motor working on all 6. What would I be noticing if it wasn't?

how did they determine the o2 was good?? what were the crosscounts??

Roy

I don't know. The place that ran the test said that everything was ok except the cat.

cat only controls the NOX. I think you need another shop with more expierence.

Roy

are the o2 sensors hard to change

nope, easy on this model. it is on the exhaust manifold. you need a 7/8 wrench to remove it.

Roy

one last question before i stop driving you crazy. The blazer has been getting progressively harder to start. sometimes have to turn the key 15 - 20 times to get it to turn over. Starter was replaced. Can you give me an idea where to start trying to correct this?

first, does it crank?? if it does, then i would be looking at fuel pressure.

Roy

I will look into that. You have been very helpful. I will be back I am sure. Have a great weekend.

thanks, you too

Roy