ford ranger 3.0 misfire

[omgitzjojo]

I have 2002 ford ranger edge 3.0 auto trans 210k miles. I have bad fuel economy. I get 180 miles to a fuel tank no matter how grandmaish i drive. And have rough running engine idle and while driving. Especially can feel it in the steering wheel. Replaced spark plugs, wires, o2 sensors, fuel filter, iac valve, MAF sensor, and fuel injectors. I only have evap code p0457.(dont think that matters). I honestly think maybe the spark plugs i have suck or something. Ive had the truck for 5 monthsand there was a vacuum leak idk if the miss was before spark plugs or not. I heard someone say bosch double platinum caused detonation in there 3.0

 

[Uncle Gump]

Ditch the Bosch Plugs and buy Motorcraft or Autolites.

I personally wouldn't do another thing until it had new plugs.

 

[omgitzjojo]

You think i should? I dont have detonation, i know thats what it looked like i said. If you still think i should i will. lmk

 

[Blindmullet]

Go through some of the cam synchronizer troubleshooting and check your cats.

 

[omgitzjojo]

Not gonna lie idk how to check that stuff. My long term fuel trim numbers aren't good. 13% and 19%. I tried motor craft plugs. Did nothing

 

[Paladin13]

I've got a 2001 Edge 3.0 and had a miss, found the head gasket was just starting to leak into the cylinder.

 

[omgitzjojo]

I don't know if i have a miss actually. I think its just engine vibration. Could it be because i have play in power steering pulley? I found it has play

 

[Rearanger]

You're going to have to determine if this is isolated to one or two cylinders, a bank or all cylinders.

You can pull plug wires one at a time to see if the "rough running" gets worse or stays the same. A compression test would also help provide info.

The + fuel trims show lean burn as the ECU tries to add fuel. Lean burn can cause misfire. Test fuel pressure.

Most diagnosis starts with testing battery voltage then coil pack primary if hunting electrical problems.

 

[omgitzjojo]

Yup engine ran worse with each plug wire out at a time. I did compression test a week ago and the numbers are 160,165,170,180,180,180,180. The last time i did fuel pressure was 5 months ago it was 60 psi. While the engine was running i unplugged the iac and the rpm only dropped 100 so it idled at 900.

 

[Rearanger]

It seems you should pursue the lean fuel trims. If injectors have been replaced and you have no vacuum leaks and fuel pressure is OK then I'd try testing sensors that tell ECU to correct fuel trim, maybe IAT for intake air temp. Your fuel trims are high but not enough to trip a code.

I don't know if the 2002 has an EGR (vacuum source).

A skilled and experienced scan mechanic can read data which should track down the cause if you want to spend money on that instead of parts guessing.

 

[omgitzjojo]

The IAT is built into the MAF sensor and i've already replaced it 10k miles ago. Also there is no egr for 2002 3.0

 

[omgitzjojo]

Also when you unplug the iac the engine rpm should drop to like 4-500 rpm and if not it indicates a vacuum leak. However idk where the leak would be. I previously had a vacuum leak and it was brake booster that i replaced