Taurus Car Club of America : Ford Taurus Forum banner

1 - 13 of 13 Posts

·
Registered
Joined
·
182 Posts
Discussion Starter #1
I've got 196K on a 2002 Vulcan. It has had a bottle of Techron every oil change (3K miles).

It had developed a rough ide when first cranked which has evolved into a random miss when first cranked. The miss goes away after a short distance. Runs fine otherwise. Good fuel mileage.

I have replaced spark plugs and checked spark plug wires. No change. We finally got an error code which points to cylinder #3.

Does this sound like an intermittent fuel injector on cylinder #3?

Is it time to replace all of the injectors? Would a professional cleaning help? Should I replace just one injector or all of them? Finally, should I go with Ford (Motorcraft) injectors or aftermarket injectors?

Thanks.
 

·
Registered
Joined
·
1,801 Posts
I would think you might want also post up other information on this like when you last changed plugs, wires, coil, etc and the brands used.

Does this miss happen hot or cold?
 

·
Registered
Joined
·
182 Posts
Discussion Starter #3
To answer your questions....
Spark plugs - just replaced
Spark plug wires - 30K miles ago (Belden wires)
Coil bank (no distributor) - original
Fuel filter - just replaced.

DTC: P0316 and P0303

The problem originally occurred at cold crank-up every morning. Now it will occur some times when the engine is cranked at operating temperature. The problem does not last for long - at least not yet.
 

·
Registered
Joined
·
182 Posts
Discussion Starter #5
Is there any easy means to measure the spark output of the coil pack? Sounds like a test requiring specialized Ford equipment.
 

·
Registered
Joined
·
1,304 Posts
Is there any easy means to measure the spark output of the coil pack? Sounds like a test requiring specialized Ford equipment.
http://www.taurusclub.com/forum/82-maintenance-repair/173490-how-understand-diagnose-misfires.html

Would be a good idea to read all the way through, but the section with the video 'cylinder drop test' should especially help with the coil testing. Also, being that they are at 30k, I would do the 'spray water mist around the wires in a dark area' test on those Belden wires.
 

·
Registered
Joined
·
22,642 Posts
^+1 on performing the cylinder drop test. A much better/conclusive test than the primary/secondary resistance tests. Easy to do on a Vulcan, impossible on a Duratec. If you've swapped plugs/wires, coil pack check/replacement is on deck.
 

·
Registered
Joined
·
182 Posts
Discussion Starter #9
Found the problem. I swapped the sparkplug wires between cylinders 3 and 4. I finally got another DTC. This time it was for cylinder #4. Sounds like we need a new coil pack.

Any thoughts about OEM vs. aftermarket?
 

·
Registered
Joined
·
1,304 Posts
Any thoughts about OEM vs. aftermarket?
None personally, but many here have said that they would go for a U-pull OEM coil in good shape before anything other than new Motorcraft or BWD.

Also, if it were me, I would probably check resistance on all of the individual plug wires when installing the new coil. (You mentioned that the wires were checked during troubleshooting, but not the method used to check)
 

·
Registered
Joined
·
182 Posts
Discussion Starter #11
A new Motorcraft coil pack is on the way. Being an electrical engineer, the resistance of the sparkplug wires was the first thing I tested. I even substituted a wire from another set for the affected cylinder.
 

·
Registered
Joined
·
9,730 Posts
A new Motorcraft coil pack is on the way. Being an electrical engineer, the resistance of the sparkplug wires was the first thing I tested. I even substituted a wire from another set for the affected cylinder.
Maybe you have a comment about carbon tracking.
I had this twice on the same car, year apart. Paid Ford garage to diag, they said wires #2 #3 carbon tracked. I let them put new wires on. Then I got it home, running fine, so I changed all the plugs. Same thing one year later, #1 as in the pic. I replaced only one wire with a used one and used good plug.

There is a difference between the upper damaged plug and the lower good plug. It is the top connection, Upper plug is loose in any wire. Bottom one is tight in any wire.

This does not misfire. Makes the car run bad. Recording says this causes the spark timeing to way out of line random spark advance jumps according to the OBDII.

So, we have a spark running around inside the boot, but not going to ground.

What the hey!

-chart-
 

·
Registered
Joined
·
182 Posts
Discussion Starter #13
I put in the new Motorcraft coil pack today and the problem was solved!
 
1 - 13 of 13 Posts
Top