I've got a 1998 Ford Winstar that I've had for years.It's been a very good vehicle.Lately I've been having problems with the check engine light coming on and staying on. I had it checked at 2 different places and was told that the code coming up when tested was P0304 ( Number 4 cylinder misfiring.) We recently took a trip in it and almost didn't make it back home. As I said earlier, this van has been like a very good friend. I've also noticed that when I start up the van, the battery light on dashboard stays on for a few minutes. Last year I replaced the alternator,engine belt and a tension pulley. I've also noticed that I need to put water in it quite often. It's not visibly leaking anywhere. I've also recently replaced the spark plugs and wires. Anyone know what I can do to correct this?
Thanks, for any help.

 

If you are adding water quite often with no leaks, and have a misfire, then the coolant is going somewhere. Is it going into the motor oil? You would know by changing the oil and looking for coolant to be the first liquid coming out of the drain plug.

 

No sir. I've checked the oil regularly and there is no sign of oil residue in the radiator or coolant reservoir. The #4 cylinder misfiring code is still showing up when I get it checked @ the local auto zone store. I've switched the number 4 plug wire with one of the other spark plug wires, but still get the same reult.I've been told that the coil pack could not be the problem because only one cylinder is misfiring. I've thought about the fuel injector to that plug and cylinder, But it seems you have to take the intake manifold off to get to the injectors. I though of maybe switching out two of the injectore and having it checked out to see if the problem switches over to the other cylinder. Got any ideas on how to check that coil? thanks for any advice you may have for me.

 

p0304 is cylinder 4 misfiring. This could be any number of reasons.

1. Bad plug
2. loose lead
3. Bad Ignition coil
4. Ignition circuit going bad
5. Injector failing
6. Upstream HO2S have a build up of carbon on them
7. Compression pressure issues
8. Timing belt needs replacement or adjustment.
9. Crankshaft position sensor dirty or failing
10. Air intake dirty of failing
11. MAP Sensor failing
12. Fuel pressure dropped or even have a clogged fuel filter
13. Crankshaft position sensor circuit and connector failures

Putting 2 and 2 together I would look at the plugs, leads, O2's and check your injectors. Without really being able to see it first hand I am guessing at what would need to be replaced, but with the indications and codes it generally falls into one of the 4 i pointed out.

 

Thanks for the help. When you refer to leads, are you talking about the plug wires? If so would that not be the number 4 cylinder plug wire?

 

Yes plug wire's

 

I'm hoping to be able to work on it tomorrow after work . If not maybe this coming weekend. Do you know of any possible to check the coil to see whether it's bad?

 

Yes to see if you are getting a good spark for that cylinder you can use a spark tester or use an old spark plug in the #4 wire and ground the body of the plug or tester and have somone crank the engine to see the condition of the spark. [hr]Also if you can reach it try to tap the #4 injector while it is running to see if it will run better if it does you will need a new injector.

 

I will give it a whirl tomorrow and se how the coil ckecks out. Thanks for all your help and have a wnderful evening. And Thanks Again

 

Well, I've been trying to log into this website without much success, but I have prevailed and here I am again. I've tried the spark plug checking and seem to get a very good spark from the #4 wire from the coil pack. Does anyone know if I have to remove the intake manifold to check the #4 fuel injector? If so can I have some kind of guidance on how to check it properlY?
Thanks