Multiple misfire codes

[modelageek]

2004, 3.0 5 speed 108k. I have had a lingering p0304. I think it is a valve. Today the truck all of a sudden started running very bad.

New Sparkplugs, coilpack and fuel filter.

I pulled into a parking lot and checked codes.
P0300
p0302
P0304
p0306
P0353 pending

Thoughts?

I had just got 10 gal of gas about 30 miles before this happened.

 

[RonD]

3.0l has known issues with CPS(cam position sensor) and Cam Syncro shaft
http://www.therangerstation.com/tech_library/camshaft_position_sensor.shtml

The CPS is used to time the fuel injectors, chronic mis-fire(0304) could be caused by CPS, or a dirty injector.

At 108k if it hasn't been changed it should be even if it is not the source of the current problem.

Yes, could be some bad gas(water in it), that is causing the new misfires, there are additives like HEET that help remove water from fuel.
Ethanol mix fuel also helps remove water.

Water is heavier than gasoline so when vehicle sits the water will settle to the bottom.
Fuel pump picks up fuel from the bottom of the tank...........
So if missing is worse at start up then gets less as you drive, water could be the problem.

 

[modelageek]

3.0l has known issues with CPS(cam position sensor) and Cam Syncro shaft
http://www.therangerstation.com/tech_library/camshaft_position_sensor.shtml

The CPS is used to time the fuel injectors, chronic mis-fire(0304) could be caused by CPS, or a dirty injector.

At 108k if it hasn't been changed it should be even if it is not the source of the current problem.

Yes, could be some bad gas(water in it), that is causing the new misfires, there are additives like HEET that help remove water from fuel.
Ethanol mix fuel also helps remove water.

Water is heavier than gasoline so when vehicle sits the water will settle to the bottom.
Fuel pump picks up fuel from the bottom of the tank...........
So if missing is worse at start up then gets less as you drive, water could be the problem.

Update.

I cleared the codes and then drove about 1000 feet. I checked for codes. Got

P0300
P0302
P0306

I believe the 2/6 are a pair.
I tested resistance on the 2/6 and got 8.7k. I tested the 1/5 and 3/4 and got 10.56k

I am thinking i blew that pair in the coilpack and the p0304 was from my earlier issue. Thoughts?

 

[Chris_1]

I had those codes on a 3.0 - turned out to be low compression on 2 cylinders 9it also revved smooth but idled rough. But if you just bought gas and then started getting misfiring it would be awful coincidental if they are not related. Gas line antifreeze or those other products mentioned might help. The main active ingredient in most of those is methyl hydrate, what it does is disperse through the fuel, absorb the water and carry it through to the engine and help it burn off.
Where you buy your gas can be really important - the big chains are much more careful about their fuel handling, plus they put good additives in like gas line antifreeze in the winter.
Another thing to be careful of is - if you see the fuel delivery truck at the station, buy your gas later or somewhere else. What happens is, all the water and other contaminants settle to the bottom of the tanks but when they hook that big fuel hose on and start pumping a truckload of fuel in there, it mixes everything up, then you put a bunch in your truck - doesn't bode well for trouble free driving.
Well we can hope it something as simple as bad fuel. Good luck

 

[modelageek]

Solved:

I bought the cp from autoparts international in July. I called the store and the manager said it had a 90 day warranty. He said he would take it back anyways. However i was 25 miles from that store and 1 mile from another autoparts international. I limped it to that close store. I had to buy one from that store for $60. I will go back to the other store and see what happens. ....crappy Chinese parts!!!!

Thanks for the help.

 

[RonD]

A vacuum gauge is not expensive, and can tell you alot about engine problems or eliminate them as problems.
Google: engine vacuum readings
This would be for the 0304 code

Ford coil packs usually run at 6,500-11,500 ohms on the plug wire connections(secondary).
Primary should run.5-1.4 ohms for each coil
Warmed up will change resistance, and if you test at the end of the plug wires and not at the coil, resistance will be higher.

The waste spark system fires one spark plug from electrode to ground(normal spark) and the other spark plug on that coil from ground to electrode(so reverse spark), which can be slightly weaker.
Since both spark plugs fire on the power AND exhaust stroke you can reverse the wires on the coil, giving "normal" spark to what used to be the "reverse spark" cylinder, and see if that makes a difference.

 

[modelageek]

A vacuum gauge is not expensive, and can tell you alot about engine problems or eliminate them as problems.
Google: engine vacuum readings
This would be for the 0304 code

Ford coil packs usually run at 6,500-11,500 ohms on the plug wire connections(secondary).
Primary should run.5-1.4 ohms for each coil
Warmed up will change resistance, and if you test at the end of the plug wires and not at the coil, resistance will be higher.

The waste spark system fires one spark plug from electrode to ground(normal spark) and the other spark plug on that coil from ground to electrode(so reverse spark), which can be slightly weaker.
Since both spark plugs fire on the power AND exhaust stroke you can reverse the wires on the coil, giving "normal" spark to what used to be the "reverse spark" cylinder, and see if that makes a difference.

thanks Ron.....The issue seems to be resolved with the new CP. I brought the old one back and the guy gave me my money back..........I bought a new Dayco Tensioner while I was there..........it looks like I need a Torx 50 to remove the bolt

Ron.....I have another thread that you helped on about the P0304.. http://www.therangerstation.com/forums/showthread.php?t=142360 ..I am pretty convinced it needs a new head..........I will inspect the spring on #4 when I pull the VC off incase by a small chance the valve spring is busted...........The issue kind of comes and goes........weird.........I would think it if was a burnt exhaust valve it would always be there.

 

[RonD]

This is a Ford TSB about '04-'06 3.0l engines

**************************
TSB 05-26-3

FORD: 2004-2006 Ranger

ISSUE
Some 2004-2006 Rangers 3.0L-2V "Vulcan"vehicles may exhibit:
- Malfunction indicator lamp (MIL) on with diagnostic trouble codes (DTCs) P0300-P0306 and P0316
- Rough running at various RPM
- Rough idle
- Misfire

ACTION
This may be due to an engine exhaust valve seat recession causing a loss of compression. Refer to the following Service Procedure to diagnose exhaust valve seat recession.
SERVICE PROCEDURE
1. Perform a power balance rest to clarify if a cylinder is misfiring. Identify and keep record of any cylinder that has a concern.

2. Perform a manual compression test with the spark plugs removed to locate any cylinder that may have low compression. Refer to the appropriate Workshop Manual, Engine System, General Information, 303-00.

3. If no low compression is found per shop manual instructions, proceed with normal misfire diagnostics per the Powertrain Controls/Emissions Diagnosis (PC/ED) Manual for the appropriate model year.

4. If low compression is found and it is a cylinder that had a misfire on power balance, perform a leakdown test to determine the source of leakage that may be causing the low compression. Refer to the appropriate Workshop Manual, Engine System, General Information, 303-00.

5. If low compression is found in a cylinder that did not have a misfire detected then proceed with normal base engine diagnostics per the Workshop Manual, Engine System, General Information, 303-00.6.

If the exhaust valve is identified as the source, replace both cylinder heads with the newly released service cylinder heads. Refer to the appropriate Workshop Manual, Section 301-01A.

PART NUMBER / PART NAME
6U7Z-6049-A / Cylinder Head Assembly


*********************************

Yes, burnt exhaust valve would show all the time.
Floating valve seat would come and go as it was either sealing cylinder or wasn't sealing cylinder

 

[modelageek]

This is a Ford TSB about '04-'06 3.0l engines

**************************
TSB 05-26-3

FORD: 2004-2006 Ranger

ISSUE
Some 2004-2006 Rangers 3.0L-2V "Vulcan"vehicles may exhibit:
- Malfunction indicator lamp (MIL) on with diagnostic trouble codes (DTCs) P0300-P0306 and P0316
- Rough running at various RPM
- Rough idle
- Misfire

ACTION
This may be due to an engine exhaust valve seat recession causing a loss of compression. Refer to the following Service Procedure to diagnose exhaust valve seat recession.
SERVICE PROCEDURE
1. Perform a power balance rest to clarify if a cylinder is misfiring. Identify and keep record of any cylinder that has a concern.

2. Perform a manual compression test with the spark plugs removed to locate any cylinder that may have low compression. Refer to the appropriate Workshop Manual, Engine System, General Information, 303-00.

3. If no low compression is found per shop manual instructions, proceed with normal misfire diagnostics per the Powertrain Controls/Emissions Diagnosis (PC/ED) Manual for the appropriate model year.

4. If low compression is found and it is a cylinder that had a misfire on power balance, perform a leakdown test to determine the source of leakage that may be causing the low compression. Refer to the appropriate Workshop Manual, Engine System, General Information, 303-00.

5. If low compression is found in a cylinder that did not have a misfire detected then proceed with normal base engine diagnostics per the Workshop Manual, Engine System, General Information, 303-00.6.

If the exhaust valve is identified as the source, replace both cylinder heads with the newly released service cylinder heads. Refer to the appropriate Workshop Manual, Section 301-01A.

PART NUMBER / PART NAME
6U7Z-6049-A / Cylinder Head Assembly


*********************************

Yes, burnt exhaust valve would show all the time.
Floating valve seat would come and go as it was either sealing cylinder or wasn't sealing cylinder

thanks Ron.............I pretty much did everything up to the leak down test....I bought a leak down tester but it was defective and I could not use it.......my compression in #4 goes from 85 to 160....depending on how the wind is blowing.........someone said it could be a broken valve spring......I am not exactly sure what a floating valve seat is?........

.if I had a garage available I would just tear the heads off and throw new ones on.....hopefully It makes it to the spring......and I can do it in the driveway.......

 

[modelageek]

thanks Ron.....The issue seems to be resolved with the new CP. I brought the old one back and the guy gave me my money back..........I bought a new Dayco Tensioner while I was there..........it looks like I need a Torx 50 to remove the bolt

for anyone concerned.........the bolt for the tensioner was a torx 50...........I have the flat serp bar tool ....it came in pretty handy...........I used the Dayco tensionor..........it comes with its own 13mm hex bolt............the tensioner appears to have solved my issue......

 

[enjr44]

Just lurking; but, I have a question.

What problem did the "new Dayco Tensioner" solve?

Ed

 

[RonD]

thanks Ron.............I pretty much did everything up to the leak down test....I bought a leak down tester but it was defective and I could not use it.......my compression in #4 goes from 85 to 160....depending on how the wind is blowing.........someone said it could be a broken valve spring......I am not exactly sure what a floating valve seat is?........

.if I had a garage available I would just tear the heads off and throw new ones on.....hopefully It makes it to the spring......and I can do it in the driveway.......

A head, any head, doesn't have valve seats, they are installed in the head after it is cast, like valve guides are.
This seat is what is ground at an angle to match the valve's angle to get a good seal.
These seats can be removed and new ones installed.

If there was a casting or measurement problem, a seat could get loose when head expands from heat, so it is "floating" instead of tight.
Exhaust valve and seat are the hottest since it isn't cooled by incoming fuel/air, so that would be most likely seat to come loose.
This is not like it is flopping around in there , just moved so closed valve isn't a tight seal on each cycle of that cylinder.
So compression changes depending on how the seat is sitting.

Over time the above will lead to a burnt valve as the escaping gas wears a bit off the valve each time, but valve rotates so it won't happen quickly.