2004 Ford Ranger 4x4 missfire in #4 cylinder??

[fazzer]

Hello my first post. I have a 04 Ranger 4x4 with 30k on in in great shape. I had a check engine light come on and I had it scanned at my local parts store, and came up miss fire on number 4 cylinder. I had washed the engine a day before and no problems that day. I have been carefull doing this for almost 5 years now. Any thoughts on what I should look for, or to do. I do have a warranty until 75K for most electrical issues with a $100 deductible. Should I try and replace #4 plug, cap, and rotor? What would be the cost for this? My warranty is pretty good not sure it would pay for plugs though? Any thoughts would be very helpful!!!

[theoldwizard]

What engine ?

Have your parts store clear all the error codes and drive it for a week. If the problem does not return, forget about.

[BroncoJoe19]

I don't know what engine you have, but it is quite possible that you have a coil for each cylinder. IF so there is a low voltage conenction for each coil. Try pulling the connector to #4 clean and dry it (if wet) perhaps put a little dielectric grease on the connections, and see if it works.

IF not... I would replace the coil for the #4 cyl. It'll cost less than the deductible. I think about $60.

[Rob F]

Did you ever find out the problem? I have a 98 with a 4.0 and I have the same problem with a miss fire on #4. My truck only has 1 coil so I have a hard time thinking it would be the coil because this has happened twice and I had the code cleared after the first time. Any thoughts?

[BroncoJoe19]

Rob,
You are absolutely right that it wouldn't be your coil. You have a significantly different igntion system.

First thing to check is... your cap and rotor, if the contacts look at all crapy, just replace them. Be careful... do one wire at a time, use a little dielectric grease on each boot, just a smear, and make sure that put each wire back onto the new cap exactly where it originated from on the old cap.

Check the plug and at least clean and regap it, if not replace it for a couple of bucks.

Check the resistance of the plug wire from one end to the other, and compare it to the ressitstance of another wire of similar length. IF it is different, compare it to another, and if again different, (significantly) replace it.

Run the engine in relative darkness. See if there are any sparks under the hood. Don't stick your head in there, or wear loose clothing that could get caught. Sometimes spraying a little water from a spray bottle will make the arching more evident.

Let us know how you make out.

[msandman57]

Did you ever find the cause of the miss?
I also have a 2000 Explorer 4X4 with a reoccuring #4 cyclinder miss, changed plug, wire injector, comes back soon after any repairs.

[LastTudor]

I hate to sound stupid, but I didn't think any of the 4.0's had distributors. I know even my 92 Ranger 4.0 had a coil pack.

[BroncoJoe19]

Damn.... too many different ignition systems, and they vary not just from year to year, but from vehicle to vehicle. When Rob F stated that he just had one coil, I was thinking One coil... One coil wire! NOT one coil pack... six wires!

[LastTudor]

Originally Posted by BroncoJoe19

Damn.... too many different ignition systems, and they vary not just from year to year, but from vehicle to vehicle.

You think we have it bad, you should have seen AMC. When I sold parts, people would get so angry when they'd come in for a cap and rotor plugs and wires and we told them the distributor could be a Prestolite, an AC Delco, or a Motorcraft distributor, and that they'd have to bring in the old one to match it up. I remember that in one model year in the mid 70's they had like 5 or 6 different distributors. AC, Presto, or Motorcraft, but some were points and some were electronic. It was a nightmare.

[BroncoJoe19]

Oh... yeah.... I remember now I had an AMC gremblin. I loved that car! But yeah some parts would be mopar, others ford or chevy.