Running very rich-91 navajo 4.0 v-6

[miked666]

I do not know where to start-exhaust smells rich, gas mileage is in the toilet(10 mpg), sooty tailpipe, weak acceleration. Check engine light comes on after about four miles. Put new plugs in, air filter, muffler. Cannot afford to put gas in every 150 miles anymore.

 

[liqhx2]

#1 thing to check for is the Fuel Pressure Regulator warm up the motor shut it off pull the vacum line off the FPR and then start it back up if gas comes out of where the vacum line connects to then you need a new fpr the FPR is located next to the intake manafold on the passenger side and its a little hard to see if your not looking strait down on the motor

 

[MrShorty]

The next thing to check, since the CEL comes on, is to pull the trouble codes from the computer. Look under "tests" at www.dalidesign.com/hbook/eectest.html

 

[slow-demon]

check the fuel pressure..symtoms indicate that its very high. A bad fuel regulator. How do I know..mine did the same thing.