2003 Ranger 1 Scan 5 Codes

[aquajock_98]

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. It 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.

Well this weekend I attempted to hunt down the problem without much luck.

- 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

Any recommendations on where to go on troubleshooting this.

[Mike J.]

I highly suggest you get a repair manual. It will help you diagnose your problem.

Your codes are telling you that you're having trouble with one side of the engine, cyl 4-6. My first inclination is that your ignition pack is bad. The Hanes manual gives directions on how to test the primary and secondary coils.

The firing order is 1-4-2-5-3-6. Notice anything here? The side with the trouble is after the good side fires. So, if the ignition pack isn't sufficiently charging before the next cylinder must fire, you'll get a miss fire. Also, two spark plugs are being fired at a time, one on the intake compression stroke and one on the exaust compression stroke. So, with first number the power piston and second number the exaust piston, here's how it's firing: 1&5-4&3-2&6-5&1-3&4-6&2. When you crank the engine the Camshaft Position Sensor always finds and fires cylinder 1 first. It does this from the 36 tooth crankshaft pully. The missing tooth (#37) gives it the reference it needs to send to the computer to know where each cylinder is located. So, a bad coil will always be symptomatic in the same sequence.

I doubt that the Camshaft sensor is bad, since it knows where cyl 1-3 are located.

Finally, there could be some other common error in the intake to the cyl 4-6 bank. The lower compression could be an indicator of the problem. Posibly a bad intake gasket. I've found previously a problem in one bank is due to water getting into the intake and fouling the plugs. Check the vacuum with a guage, a rocking vacuum needle will indicate a leak, which would also cause lower compression on the effected side.

Finally, check your cyl 4-6 exhaust manifold/pipe for a leak or blockage.

[davidw]

i got my check engine light on as well,,,,,,,,heard if the light is blinking your damaging your rig......

[aquajock_98]

I have replaced the coil pack with a motorcraft one and that did make a difference. I also gave it a seafoam treatment that made no difference.
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?

[Mike J.]

Check your exhaust for a split cat system. Some vehicles have a pre-cat in each exhaust pipe before the Y junction to the main cat. It's possible the pre-cat could be blocked on the 4-6 bank side. A blocked main cat, or single system cat, would give trouble in all cylinders.

[aquajock_98]

I took my truck to the Dealer today and just got a call that I have low compression in #6 and that it is a problem in my valve train. From this they say that I need a new engine because I have a 120,000 miles on the truck. They don't recommend just fixing the head.

[Mike J.]

Some would agree with the Dealer, only because fixing the one head could unbalance the engine and cause the other side to fail as well. Besides, the dealer would be out several thousand dollars for the new engine.

Since you don't know exactly what is bad, you might as well take the head off and see what's up and repair it. It could be a burnt/bent valve, pushrod, sticking lifter, or head gasket. The key is to remove the other head as well, even if all you end up doing is replacing the head gasket. More than likely you're going to send the heads to be resurfaced and cleaned, etc. Again, do them both, not just the one that's bad. This should keep them balanced and reduce the probability that the increased compression will cause problems with the lower engine, due to wear.

[aquajock_98]

Yeah I realize I would have to do both but the dealer wants me to buy a long block, do you think that is neccessary

[Mike J.]

Sounds like the dealer is just after your money.