My 1999 dodge durango idles and runs terrible, sitting at an idle it ranges fro 400-1400rpm and stalls out occasionally, it also runs rich all the time and puts out block soot when I give it gas, I have replaced the tps sensor, map sensor, idle air controlle, alternator, and spark plugs, help
What led you to all those random parts? Have you checked for a vacuum leak? That will cause a varying idle speed, and it will introduce extra air that the Engine Computer will try to compensate for by adding more and more fuel. Too much unburned fuel causes black smoke from the exhaust.
December, 8, 2012 AT 10:40 PM
Already checked for vacuum leak, after I put in the new map sensor and new spark plugs it ran terrific for about 30mins then started doing the same thing
December, 8, 2012 AT 10:46 PM
The first thing to do is check the diagnostic fault codes. Cycle the ignition switch three times from "off" to "run" within five seconds, then watch the numbers show up in the odometer display. If there's no codes, you'll need a scanner to view live data to see what the Engine Computer is seeing from the sensors and how it is responding.
December, 8, 2012 AT 10:53 PM
I will try checking the code on the diagnostics, but when I put it on a scanner it threw a code for tps, po123 I think, we changed tps, and map sensor which both can cause it to throw that code and neither was successful, could a faulty computer cause this behavior?
December, 8, 2012 AT 11:00 PM
Or is fuel pressure and regulation a possible solution
December, 9, 2012 AT 12:02 AM
Don't worry about fuel pressure until we eliminate the cause of any codes. Code 123 isn't related to the map sensor. That code will set if the tps is unplugged while the ignition switch is on. Did you erase that code and did it come back after you put the new one on? If it comes back, what voltage is it reading on the scanner when you run the gas pedal from idle to wide-open-throttle?