Intermitting misfire driving me crazy & broke. Help!

[2001SportDude]

2001 Explorer Sport 4.0 V6 SOHC
Codes: P0171 & P0301

About 1 month ago I started the truck in morning and right away I noticed one of the cylinders was not firing. Lasted about 5 minutes then smoothed out.
After about 3 days of the same the CEL came on.
After about a week the problem stared lasting longer. About 30 min-1 hour b4 smoothing out.
Took to AutoZone and they told me cylinder #1 was misfiring and gave me the above codes.

After reading here of the notorious intake gasket leak fouling the plug....
1st step was I removed the plug on cyl 1 and sprayed compressed air into the cylinder to remove coolant if any (didn't notice any come out) Replaced with new gapped Autolite plug.
NO change. Still misfiring even with new plug.

Later I removed the spark plug wires. Upon inspection of the old I noticed plug #1 wire had a small spot worn through. I was eager the wires would cure the problem.
NO change.

Disappointed I decided to replace the coil pack.
Again No change.

Currently the truck runs on 5 cylinders most of the time. Sometimes it might smooth out (but never runs good in morning) Sometimes it runs like a champ for 10 mins later in day then runs like crap again. This is driving me crazy & I don’t have any more money to dump into the truck (unemployed)

I have a friend interested in the truck and possibly wants to buy it this weekend so I NEED to get it running properly b4 doing so.

Sorry if long post.
I can really use ANY help and advice I can get on here right now because I’m completely frustrated.

 

[Turdle]

Sounds like a dead injector

 

[2001SportDude]

Thanks for the reply Turdle. Injector has crossed my mind too. Besides the obvious can you explain (from my story) why you think its an injector? Is it common to be intermittent like this?

 

[Turdle]

Thanks for the reply Turdle. Injector has crossed my mind too. Besides the obvious can you explain (from my story) why you think its an injector? Is it common to be intermittent like this?

Well, you have the spark surrounded, so if the compression is good ( which cannot be intermittent) than I assume it is a fuel problem. The only part in the fuel system which is unique to cylinder one is the injector ( and wiring)

When I said dead injector, I meant one which was not firing. This could be the injector itself. However, since it is intermittent, I would assume a poor connection in the wiring.

 

[2000StreetRod]

Test the injector

P0301 Cylinder 1 Misfire Detected
P0171 System too Lean (Bank 1)

Cylinder 1 is in Bank 1. The PCM has detected low power output for cylinder 1.

Did you check for spark at the plug? When you pulled the #1 spark plug did it look like it had been running lean?

I agree with Turdle that you should test your cylinder #1 injector. First, disconnect and then reconnect the injector electrical connector. That will clean the contacts a little and make sure there is a good connection. With a noid light you can check for current to the injector. If it's getting current then it may be blocked or failed. You could test it for an open or short. But whether the solenoid is bad or it is blocked it still will have to be removed for repair or replacement. If you had more time, you could add a bottle of fuel injector cleaner to your fuel tank but it could take a hundred miles or more to have an effect.

 

[2001SportDude]

Thanks again Turdle

Did you check for spark at the plug? When you pulled the #1 spark plug did it look like it had been running lean?

Yes, I pulled the plug wire on #1 put a screwdriver to the block. It definitely had spark. However it was orange. (somebody told me it should be blue?) A test on the other side of block turned same results, orange.

Actually I put Lucas injector cleaner in yesterday but only put 20 or so miles on it so far.

I just ordered an Motorcraft injector on eBay for $30 delivered. Should have it next week.
Ill try the test you suggested and get back with results.

Thanks for the replies and any other advice/suggestions anybody has is greatly appreciated!

 

[kythri]

How did everything work out for you?

 

[2001SportDude]

How did everything work out for you?

I got a job now so I didnt have time to try the tips advised in this thread . I called the service adviser at the local Ford dealer (cool guy) and he really seems to think its a vac leak somewhere or bad intake manifold/gasket.
In any case I ended up selling the truck cheap and the buyer said he will get to the bottom of it.

Thanks for all the help guys.