2002 Dodge Dakota Repair Question
Asked on July 12, 2012
I have a 3.9l. obdii says the code is a p0301 (misfire #1 cylinder) how do i fix the problem?
I have a 2002 dodge Dakota 3.9L. I was recently driving home one night and the check engine light came on (it stays on and does not blink)when I got home I hooked the truck up to the OBD II and I received a P0301 (#1 cylinder misfire). I tried replacing the Plugs, Wires, Distributor cap, Rotor, ignition coil, drive belt and the air filter and rest the code about 50 miles later the light came back on . I switched the #3 fuel injector with the #1 to see if it was bad (it wasn't) . I also checked the wires to the injectors to make sure they are getting power and they were. I checked the pressure coming from the fuel rail and it was at 49 PSI. I did a compression check and here are the results 1. 155 PSI, 3. 167 PSI, 5. 166 PSI, 2. 164 PSI, 4. 155 PSI, 6. 169 PSI. I checked the vacuum pressure from the booster lines and set the idle to 2000 RPM (a smooth idle). The pressure was at 50 PSI with a tiny bounce in the needle and the gauge said it was a normal motor. Nothing has worked so far. Any suggestions?
Replied on July 12, 2012
I recommend you check and test the crankshaft positioning sensor or replace it as you wish -start here and let me know
Replied on July 17, 2012
rasmataz, I tried the crankshaft sensor drove it 20 miles and the light came back on.
Replied on July 30, 2012
I had the truck hooked up to a computer and it said that cylinder #1 was not the problem and that it was actually cylinder #4 that had the miss. I guess 1 and 4 fire together. It also said that bank 2 (passenger Side) was running lean at idle but was ok while driving. Any advice?
Replied on July 31, 2012
Check both no.1/4 injector resistances