Failed California Smog

[4.3LXJ]

The cleaner may affect emissions until it is done going through. Run it down to empty and fill again.

[xj4life2]

Cleaner shouldn't run the co's up that high , its way to rich and not burning it. With a new cat I would have never expected those numbers. I also noticed that the RPM are very low at Idle. I'll do some checking and see what I can come up with

[4.3LXJ]

Mark, if I remember he bought a used cat. Might be the problem.

[xj4life2]

could be but its not in fuel control or the fuel pressure reg is blown and is pushing strait fuel down its neck, with the CO at 6% he would tear up at cat. i would check the fuel reg and see if its good if it is he may have a bad comp. Need a data stream to confirm but fuel control is the issue . Pull the vac line on the regulator you should not see,smell fuel and be sure you have vac at it. Other than that your back to not going into fuel control.

PS . SHHHHHH its illegal to install a used cat on a vehicle in CA.

[greenchevy]

Bought a new cat and installed it. not used.

[4.3LXJ]

Sorry

[greenchevy]

Pulled vacuum on the pressure regulator and it holds with vacuum pump. Not sure how much pressure I'm supposed to pull from it but at 5psi it holds with no drop. I then hooked up a fuel pressure gauge and the needle (shakes) around 32-34psi. When i accelerate the fuel pressure will go up 2 or 4 psi then it will go down (bellow idle psi). When i let go of the accelerator it will go back up to 32-34psi. When i turn off the engine the fuel pressure will rise to 40psi.When i pull off the vacuum from the fuel regulator the psi goes to 40psi.

[greenchevy]

I've lost 26 psi with the engine off in 30 minutes.

[4.3LXJ]

Are you running premium or regular gas when testing?

[greenchevy]

Regular

[4.3LXJ]

Our gas contains ethanol. The greenies think this is supposed to lessen our dependence on foreign oil and lower our carbon footprint. However ethanol makes gasoline molecules sticky and they don't evaporate as well and so don't atomize as well. So in effect we take a milage hit because some of our gasoline ends up being burned in our catalytic converters instead of inside the cylinders. One trick the smog guys have for marginal vehicles is to burn premium instead of regular. I do on all my vehicles when I smog. So use up your gas and then refill with premium.

[greenchevy]

Could a faulty coolant temp sensor or manifold intake sensor cause my high CO%? What symptoms do these sensor cause when faulty?

[4.3LXJ]

Faulty coolant temp sensor will make it run rich

[greenchevy]

How can I test it and where is it? Is it in the engine block?

[4.3LXJ]

The CTS is in the thermostat housing