I just took the truck to get an emissions inspection. On the way over my "check engine" light came on. I turned off the ignition then started it back up and the light went off, but I noticed the truck ran kind of sluggish.

While the guy was dong the emissions test I noticed a lot of blue smoke coming out of the exhaust and the guy is shaking his head.

The test showed my truck was running nine times richer than it should. The smoke was from gas not oil.

Needless to say it didn't pass the test, and it surged and bogged halfway home, after it cooled down a bit it wasn't so bad but still sluggish.

I told the guy I'd bring it back to him next week if I can't figure out the problem.

Any ideas?? What could be making it run so rich?

the oxy sensor, catalytic conv, and idle control valve were recently replaced but I don't know if that makes any difference.

This question was also posted on my oil pressure thread.
Thanks
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Your EGR valve is probably the culprit. Try that and see if it helps

 

If it's as rich as you say I don't think the EGR would cause that. Not saying it couldn't be bad but I would think that your fuel pressure regulator could be bad. Do a pressure test on the fuel rail. I think it should be around 35PSI.

 

Is there a way to check the egr valve?

Would high fuel pressure cause the rich reading? Are the injectors suspect to fail when the fuel pressure is increased? Kind of like an open carb float needle? I'm more familiar with carbs than fuel injection.

I don't think I have the tools to do fuel rail pressure check.
Thanks

 

Defective EGR may cause a lean condition. Defective FPR (fuel pressure regulator), or MAP sensor, or O2 sensor can cause an overly rich condition. If black smoke is noticed, the FPR may go "closed" and push 100lbs. or the diaphram can burst allowing raw fuel to enter the vacuum line and into the engine's crankcase (possibly blue smoke). The fuel pressure should be checked with the engine running, have seen the change to high pressures take up to 2 minutes. Pull vacuum line off FPR and turn key on while watching the FPR vacuum nipple for fuel to exit, if not check that pressure is between 30-40 lbs. The injection system uses a pulse width (time injector is open) and is based on correct fuel pressure, too much pressure, too much fuel.

 

If fuel exits the nipple does that indicate high fuel pressure? Can I check the pressure with a fuel pressure guage? Or should I just replace the FPR and see how it runs?

Thanks for the explanation Fordtech1.

 

Fuel exiting vacuum port denotes blown diaphram, replace it, if no fuel, check pressure and replace only if it goes high.

 

Check your map sensor, voltage output should change as the vacuum changes.

 

Check codes before buying too many parts for it. Go to http://fordfuelinjection.com and click on "Getting Codes" to see how to pull the codes.