My Ranger has a V6 3.0L EFI. It the last few weeks the idle has become rougher. When I was in fast food drive thru the check engine light came on but was blinking then became solid. The next day it has disappeared. Tonight driving home I found that it was losing power as a tried to accelerator it seemed as if it was not going anywhere. Again the check engine light came on and was blinking, after I let the engine cool awhile it is now solid.
When I checked the codes I got the following P0306, P0175, P0300, P0304, P0305, P0171, and P0316. So I have read some of the stuff here and is seems like it could be fuel related clogged fuel filter, injectors or air flow problems. I recently changed the air filter and not to long ago changed the spark plugs. Any recommendations on where to start troubleshooting this.

 

Multiple misfires. Could be a problem with the crankshaft position sensor. Also, because it's a 3.0L vulcan, you also have to consider a bad camshaft position sensor and/or synchronizer.

 

Well this weekend I attempted to hunt down the problem without much luck. I did take your advice and
- replaced the Crankshaft Position Sensor with one from Pep Boys made by Wells (SU4101) that didn't change much it seemed to have a little more power but the codes remained.
- I also replaced all the spark plugs and wires with Autolite Double Platinum Plugs (APP 104) and BWD Select Professional Wires (CH86754)
- Cleaned the MAF sensor
- Checked Air Filter still almost new
- Replaced the fuel filter with a Purolator brand one (F55523) from Pep Boys
- Replaced the Upstream (Bosch 13117) and Downstream (Bosch 15716) O2 sensors
- I checked the compression on each of the cylinders and got

Cyc 1st 2nd
1 135 150
2 130 135
3 150 150
4 125 130
5 135 130
6 125 120


- Removed and inspected the Camshaft Position Sensor. I had read the posts here regarding it and visually it looked fine I didn't see anything the struck me as wrong. Is the best bed to just replace it?
I am still receiving the codes P0306, P0300, P0304, P0305, and P0316

 

Those codes are missfire codes look for a bad coil pack or crank position sensor.

 

I agree, test the coil packs. You also should have used motorcraft wires. Those BWD wires are not meant for Ford ignition systems.

 

I did replace the crankshaft position sensor, I will look at the coil pack

 

Your engine is in better shape .None of my psi is over 100.I was told by a ford tech adviser 160 is normal for a 04 and 100 and under is not good.I also tryed a new coil same problem.The thing runs good at engine speed above 1500 rpm.But at idle the miss is there.Off idle it is gone but you can feel it.

 

I replaced the coil pack and gave it a seafoam treatment and neither made a difference. It is still running rough and misfiring.

 

Did you try to disconnect it plug one at a time and locate which cyl is not making a change.Also do this with each injector.If the one on the passenger side doesnt change it might be one under the plinum on the driver side.This should at least tell you which direction to consintrate on.

 

I would not rule out a camshaft position sensor/synchronizer (CMP) issue. If the CMP signal is out of whack it can cause a variety of problems, including misfires.

There is a growing number of issues related the CMP assembly on the 3.0L vulcan. Ford put out a TSB a few years ago regarding incorrrect installation:

https://www.ford-trucks.com/tsb/full...hp?tsb=02-22-1

But there are other problems with the 3.0L CMP assembly that are occuring more frequently these days. The gear at the bottom of the synchro shaft gets stripped because the shaft is binding up on account of a lack of proper lubrication. (That's why there's often a squeaking sound associated with the synchro failure). Once that gear gets stripped, it can no longer spin the oil pump drive shaft, which means the pump stops pumping, the engine gets starved for oil, and then it's bye bye.


I also would not rule out a valve problem. Even though the TSB you posted in the other thread says it applies to 2004-2006, that doesn't necessarily mean your 2003 is excluded. It could be a late build, for example.

 

aquajock did you ever find out what was wong with your truck. i have a 2004 and it is doing the exact same thing

 

Is it just me or his compression really low? My 87 Ranger 2.9, with 146k has about 150-160 lbs on all cylinders.

Even my lawn chipper/vacuum has around 140 lbs of compression.

I'm thinking either somehow your valve timing jumped a few degrees, or your injectors are clogged/on their way out. I would also try getting some motocraft wires as well. Fords seem to misbehave with non-motocraft parts.

 

The truck was purchased in January of 2003 so I don't think it is a late model build that would be covered in 2004. Is the best way to check the camshaft assembly just to take the whole thing out?
Some other details I have noticed when I drive it after the codes are cleared (or when it is cold) it runs pretty well until it warms up and then after a few more blocks I can feel a power loss and begins to run really rough. If it is under high load going up a hill or I rev to and hold at 4000 rpm occasionally I hear a noise like something rattling around. Almost like a bean in a can.
Could misfires be caused by a problem with the cat?

 

If the cat is rattling it could be a loose converter.And that could be cloging up the exhaust.Take a hammer and tap the converter.If you here it rattling in side the material in the cat has broken up inside.

 

If you are find that the mis-fires/bucking starts out at higher RMPs and drops to lower Rpms as the engine warms, this could be a sign of the Syncro failing. The syncro will not produce engine codes for faults over 2500 RPM per Ford. The test is to read the knock sensor cycles under 150 okay over points to Syncro. Ford does have a TSB on this as well. The other Syncro sign is a light belt type squeal that comes and goes with tempature. IE heavy stop and go traffic no squeal at or near idle, hit the highway and run ten miles or so in cold/cool weather come to a stop and the squeal returns. It will sound like belt squeal, and when you put water on the belts to check them the sound will not change.