Cel

[osmoalec]

I have a 99 Explorer with the 4L OHV. I am currently pulling codes for Misfire cylinder 6 P0306, and P0174 system too lean (bank 2). Before I had cleared the cel i also had code for O2 sensor as well as system too lean bank 1. I've read that if have codes for both banks being to lean that it's almost always a vacuum leak. What I was wondering is if this is true, and if it could cause the misfire?

 

[alohamonte]

You shouldnt just clear the CEL, your car is telling you there is a problem.

I'd start by changing the spark plugs and the 02 sensors.

 

[osmoalec]

I had just bought the truck and he said he never cleared the codes, so I wanted to see what came up while driving the truck. I plan to do plugs just as part of tune up, as well as switching to synthetic fluids. I'm just kind of eliminate everything else before I go replacing upper intake gaskets.

 

[lobo411]

The upper intake gaskets can be replaced in about 20 mins. You just unbolt the upper intake and replace three sets of rubber gaskets. The lower gaskets take more like 4-6 hours.

 

[Mike65]

I did the upper intake gaskets on my 00 Ranger 4.0 & they were fairly easy.