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"new to me" 2004 with a p0304


modelageek

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I picked up the 2004 in my sig 2 days ago. the PO said his mechanic cheeked it out and it needs an engine. it has a p0304 and sometimes a p0316.............here is what I know and have done....

I have and been driving it around for 2 days . Before I drove it away from the guys house 2 days ago I cleared the codes and swapped out the #4 plug and swapped the 4 and 5 wires. The cel came on within an hour of driving. I have cleared the codes 4 times. This might be my imagination but seems to be worse right after clearing the codes. The Cel has flashed about 3 times for about 10 seconds. It only does it while idling. The CEL has not flashed while driving. I seafoamed the truck, doing the 1/3,1/3,1/3 way. I did get a p0301 right after the seafoam but I cleared it and it has not cone back. Truck runs good beside this occasional issue. I have plugs/wires on order. I eventually will do compression test. I talked to a mechanic friend today and he thought it could be the injector. The codes I keep getting are the p0304 and sometimes p0316. Another weird thing is sometimes the cel goes out but the code is still there. All ideas are welcome.


P.S. I put my stethoscope on the cam sensor and it sounds perfect. I do have a squeak that I am calming down by spraying wd40 on the pulley bearings.

all help would be appreciated!
__________________
2004 Ranger edge, ext Cab, 2wd, 3.0, M5OD, 100k miles. Currently chasing a p0304!
 


adsm08

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I am thinking injector may be at fault as well. It is at least worth doing a compression test on 4 5 and 6 though.
 

RonD

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I would test the coil pack just to do it and get that off the table, you can test in the vehicle, or pull it out.
There are 3 separate coils in the V6 coil pack.

The Ford coil pack uses a waste spark system which means the two cylinders at TDC both fire, one is on the compression stroke(TDC) the other on the exhaust stroke(TDC).

But if two spark plugs are firing at once wouldn't 2 cylinders get the misfire code if that coil was bad???

No, the two spark plugs on the one coil are in series, so one sparks + to ground the other ground to +, yes reverse spark :)

Google: How to Check an Ignition Coil Pack the easy way

Good video How-To

Testing the coil this way doesn't mean it's 100% good, but if you do find one coil out of range it does mean it's 100% bad.
Just takes 10 minutes and then it's off the table.
 
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modelageek

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Thanks for the feedback. I am going away this weekend but will do a CT next week and post the results. It appears the intake manifold needs to cone off to pull the #4 injector?

I tested the CP. Secondary ohms on all 3 coils were all 10,600. I was not positive exactly how to test the primary but any 2 terminals I tested were all less than 2 ohms.

It appears my coilpack might be mounted backwards over the VC(even though the connector seems to be in the right place abd the 3 bolts holding the CP are in order). Here is my coilpack order.



5 1
6 2
4 3 (connection)

Front.

FYI: my coilpack is a MC
 
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modelageek

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Just looked at the coilpack closer. The cp is labeled. it is wired right, just backwards. Another one of fords better ideas.
 

RonD

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Primary coils should be under 1.0 ohm, .3-1.0 ohms is the spec

There are 4 wires to the coil pack, 1 will be 12v when key is on
The other 3 are grounds controlled by the computer to power up each coil for firing.

The test for primary coil is one probe on the 12v pin the other probe on one of the three coils ground pins, .3-1.0 ohms should be there, repeat for other two coil ground pins.

Usually pin lay out is 12v---gnd---gnd---gnd


Fuel injectors can be test with ohm meter as well, 11-18 ohms is usual range, but test the 3 on that side, and write down results.
The ohm readings on injectors are much like the compression test numbers, where the numbers aren't as important as the average difference between all the numbers.

You can also use a rubber hose as a stethoscope to listen to each injector with engine running, you can hear the click each time it opens.
 
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modelageek

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Primary coils should be under 1.0 ohm, .3-1.0 ohms is the spec

There are 4 wires to the coil pack, 1 will be 12v when key is on
The other 3 are grounds controlled by the computer to power up each coil for firing.

The test for primary coil is one probe on the 12v pin the other probe on one of the three coils ground pins, .3-1.0 ohms should be there, repeat for other two coil ground pins.

Usually pin lay out is 12v---gnd---gnd---gnd


Fuel injectors can be test with ohm meter as well, 11-18 ohms is usual range, but test the 3 on that side, and write down results.
The ohm readings on injectors are much like the compression test numbers, where the numbers aren't as important as the average difference between all the numbers.

You can also use a rubber hose as a stethoscope to listen to each injector with engine running, you can hear the click each time it opens.
OK....I tested for 12v at the wire and on my "backwards" truck it was the one closest to the front.....so I use that 12v terminal and then tested the other 3..........they were all .8 ohms....off to lake Winnipesaukee for the weekend........next week I will do a compression test.....someone had mentioned that a leakdown test might be better for a valve issue......is that true and are they tough to do?
 

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Leak down test requires a compressor set to a stable pressure, like 100psi.
You then connect a gauge on the air line and run that line to the spark plug hole.
Cylinder being tested should be at its TDC for firing so both valves are closed.
You then add the air pressure.
If compressor is providing a stable 100psi, and gauge reads 90psi, then you have 10psi leaking, so 10% leakage.

You then add some oil, couple of teaspoon, to the cylinder, turn engine over a few times, then repeat the test.
If you now get 95psi then you had 5psi ring leakage, and valves are good
If psi is still 90psi then valves are leaking.
And you can usually hear the air escaping the valve at the intake or exhaust when under constant pressure like this.
There is no time frame, 30seconds to a minute is more than enough time to test a cylinder.
Metal rings on metal walls with metal valves on metal seats are not designed to seal pressure tight, they contain explosive pressure of 2,000psi for a moment.
95% on a leak down is a newer engine.

You can do a compression test on all cylinders, then repeat the test after adding oil to each cylinder, and then compare the results, if one cylinder doesn't come up in psi then I would suspect a valve problem.
 

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.....someone had mentioned that a leakdown test might be better for a valve issue......is that true and are they tough to do?
Leak down too complicated for your needs. Just do a hot engine compression test.
 

modelageek

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back from Lake Winnipasaukee .....If anyone cares I took a picture of Mitt Romney house while I was there..........I plan on doing a compression test on 4,5,6 in the next few days. In the mean time I figure most likely I will need to be pulling the upper intake either for the head or the fuel injector......my upper intake appears like it is held on by 4 bolts....I took a picture of 3 of the bolts......one bolt, the one at the top of the picture is pretty destroyed.....I am looking for suggestions on how to remove it......and where to get new ones.....I was think I would grind the head off if it would npt turn and then soak the stem and see if I could get it out.......I have never had to extract a busted bolt before......all suggestion are encouraged.



 

RonD

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Yes probably to close in there for a bolt extractor
They look like a socket but have tapering "teeth" that dig into the head while trying to unscrew it.

Grinding it off will be hard as well but may be the only option


There are stud extractors that are similar to the bolt extractors but a little longer, they collapse in on the shaft of the now headless bolt to grip it as you try to unscrew it.

Those bolts should only have 8-14ft/lb of torque, so not super tight, just rusty from the looks of them, pair of pliers might even work :)
 

modelageek

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I got a compression tester.......this was my first time doing a compreession test..I might do it again just to verify the results....they don't seem good.....I tested 4,5,6. it was getting dark out s and buggy...........I tested 4= 80. I added a little oil..it went up to 120...i tested 5 it was 122.....i did not add oil........I tested 6 it was 150.....I did not add oil........thoughts!
 

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Either your battery is low(engine turning to slow), or your throttle plate was closed or your new compression meter is incorrect.

For a compression test you should remove all the spark plugs, have a look at each when you pull it out.
Google: Spark plug condition images

Then prop open throttle, put something on the gas pedal

Screw compression gauge into spark plug hole, hand held units don't work for this type of engine.
Turn over engine for at least 5 compression strokes, you will hear them, engine will slow down each time.
Then check gauge.
Write result down, release pressure on gauge, move to next cylinder

V6 should be at about 170, 150 would be getting low, lower than 120 would be missing badly.
So if you had a bad cylinder, it might look like this

175
165
170

160
130 << recheck this one
170

Compression test numbers will change a little each time you do it, so they are not "the word of God", but they can tell you if one cylinder deserves a more detailed examination.
10% is the general rule, all cylinders should be within 10% of each other.
So if 165 is the average on your test then all cylinders should be within 16.5psi of 165, than mean 150 to 180 is OK


Compression test with a bad gauge or not done correctly won't really get you any results you can base an opinion on.
Just be patient and try again.

80psi then add oil and get 120psi, that's a 50% improvement, which just isn't possible.
First 80psi would mean a valve issue, not rings, and adding oil won't help a valve issue only rings, so I would suspect the 80psi reading and then also the 120psi reading.
This could be your bad cylinder but the numbers are too far off.
 
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modelageek

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Either your battery is low(engine turning to slow), or your throttle plate was closed or your new compression meter is incorrect.

For a compression test you should remove all the spark plugs, have a look at each when you pull it out.
Google: Spark plug condition images

Then prop open throttle, put something on the gas pedal

Screw compression gauge into spark plug hole, hand held units don't work for this type of engine.
Turn over engine for at least 5 compression strokes, you will hear them, engine will slow down each time.
Then check gauge.
Write result down, release pressure on gauge, move to next cylinder

V6 should be at about 170, 150 would be getting low, lower than 120 would be missing badly.
So if you had a bad cylinder, it might look like this

175
165
170

160
130 << recheck this one
170

Compression test numbers will change a little each time you do it, so they are not "the word of God", but they can tell you if one cylinder deserves a more detailed examination.
10% is the general rule, all cylinders should be within 10% of each other.
So if 165 is the average on your test then all cylinders should be within 16.5psi of 165, than mean 150 to 180 is OK


Compression test with a bad gauge or not done correctly won't really get you any results you can base an opinion on.
Just be patient and try again.

80psi then add oil and get 120psi, that's a 50% improvement, which just isn't possible.
First 80psi would mean a valve issue, not rings, and adding oil won't help a valve issue only rings, so I would suspect the 80psi reading and then also the 120psi reading.
This could be your bad cylinder but the numbers are too far off.
thanks Ron, great info

By hand held, I assume you mean the ones that has a rubber stopper on the end that you hold over the sparkplug hole. the testerI have has a small chrome piece that I screwed into the SP hole and then screwed the actual tester into the chrome piece.......

I removed all 3 spark plugs from the drivers side head. I did not remove any from the passenger side( this should be OK, right?)

One thing I did not do was prop open the throttle!

I did crank the engine over for a bit as i was testing ....I had the wife crank it for a bit, stop and then crank it some more. I did this a few times until the I felt the gauge was not moving up at all.......

other then running a little rough, on and off at idle the engine runs good.....goes down the highway at 70 like a champ....

a few more clues.....the temp gauge does not work. I was wondering if maybe the thing over heated and he did not catch it!. I have checked the temp with my torque......the ect is working.....truck runs at 193. I do not see any signs of a bad HG...no water in olil, etc........however when I got the truck the rad was full but the reservoir tank was dry( I added coolant). also then I ended up putting almost 2 quarts of oil in the engine to get it to the top of the thatching. when the oil was low I think it was really just below the bottom thatching.....I was surprised it took almost 2 quarts. .I think he took it off the road in March when this thing happened so truck was sitting around for awhile while he decided what to do.... the truck is a one owner with 100k miles on it...I put my stethoscope o the cam sensor and few times and it sounds perfect. I am wondering if his syncro acted up and that caused this issue and then he replaced the syncro......it is in great shape(other then this)...I only paid $900.... I will redo this compression test........I rented the tester from AZ...maybe I will look into buying one...also....the spark plugs I pulled from the bad #4 cylinder was a newer autolite in good shape......another one i pulled was an older MC.....it looked pretty good but worn.......the gap was a little big......in the dark I misplaced the 3rd plug.........maybe I will find it today.....
 
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RonD

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The fact #4 had a different spark plug brand than the others means it was an on going issue, for the previous owner.

You really need to pull all the spark plugs for the compression test, you need similar crank speed for the compression numbers to be comparable.
When only 3 spark plugs are out the crank will be loping, so at a slower speed for one cylinder than the next.
If you can't pull the other 3 spark plugs then only pull one spark plug at a time and test that cylinder, that way each cylinder tested will have the same crank speed.

I would put your stethoscope on each injector with engine idling, you will hear the "click" when it fires, should be the same steady rhythm for all.
#4 might be skipping a beat causing the idle issue
 
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