CEL on and was not ready for testing w/ emissions. P0316, and P0300 . Had diagnostic done and showing 1 & 2 misfiring the most and wires arching. Occasional misfire on 4 & 5.
When I change out the plugs and wires will the CEL turn off by itself or must I turn it off myself and go through drive cycle again?
This is somewhat of a ‘station’ car and it has taken a while to get through the drive cycle. Really need to get emission test completed.

For background,Heads,gaskets etc done 4 years ago (10k miles ago) per TSB (they did not change out the wires or coil pack)
I am debating between Autolite iridium xp 103 & Autolite double platinum App103

I was considering Duralast 4734 wires

Any recommendations?
O
Used to use Techron cleaner in this vehicle but am afraid to do anything other than plugs so not to throw it off for testing.

TIA

 

It will eventually turn off by itself, assuming the problem is fixed.
To clear it, remove the NEGATIVE battery lug and hold it onto the positive terminal for one minute (no need to disconnect the positive terminal).
This drains any residual charge in the caps on the circuit board so the CEL will go out.
If the problem isn't fixed, it will come on again.

Use double platinum plugs in a waste spark system.
Doesn't really matter what brand.

 

Clearing via battery I will need to do drive cycle again though. So would be the same as erasing code via obd-2.
Thanks!

 

It doesn't actually clear the code, but it does turn the CEL off.
To clear the code, the reader has to pugged in and the code cleared that way using the reader software.

 

Thanks did not see this at first.

I saw I physically can not reach all wires etc so made appt for a mechanic to come in. The plugs slated from them were Motorcraft Sp-413, which are not dbl platinum. Called some dealers and this is the one slated for this ranger (even checked with vin)
Sp-500 were installed when new heads were done. Am being told 500s were for flex engine. Now I am concerned what the wrong plugs could have done.

I already picked up the autolites.
Is there a great difference with the motorcraft and autolites?

 

The Autolites and the Motorcraft are supposed to be the same, since Autolites makes the plugs for Ford, AFAIK.
If you don't use double platinum plugs, it won't hurt anything, they just won't last as long.

You can use single platinum in one bank and double in the other to save a bit of money.
Two plugs fire at the same time and those sets are wired in a series, so one plug is firing from the centre electrode to the edge, while the other fires from the edge to the centre electrode.

I always get confused which are firing from the centre to the edge and the other way around, so I just use double platinum all around.

Ron would be able to tell you which cylinders are firing either or, and where to use the single and double platinum plugs.

 

The codes before clearing were B1318 (low battery voltage), P0300, P0301 & P0316. I was able to drive it around and fulfill all but one of the drive cycle, It passed inspection with a new gas cap.

He got about 3 weeks out of it without CEL on, and 2 of them it was used lightly due to illness.
He was driving today in the rain, as he was getting off freeway CEL started flashing and experienced lack of power and was shaking. Engine was running, but in limp mode
Stopped for gas and used the techron. Was getting 3 codes P0304, P0316, & N/A. Was able to carefully limp home, but no power when pushed gas pedal to floor.
Since the WIres and Plugs were already changed, I decided to change the Ignition Coil. Still CEL,, though not as rough as before and after driving a couple of minutes Flashing CEL returned . Codes came up P0304, P0316, & now P0300
I was thinking of switching to the nickel motorcraft plugs, but I could not removed the installed ones due to physical limitations.
I thought perhaps the MAF was a problem and needed cleaning. So I started engine and unplugged it and engine did not turn off. I removed it and cleaned it, did the same thing and still unplugging did not turn off engine.
So I replaced MAF with a new one. Still unplugging did not shut off engine. Test drive: Still solid CEL, and missing/rough, and after driving Flashing CEL , on occasion when gave accelerator , or hit bump/hump ,it would go solid.
Got 4 codes, initially P0304, P0316, P0300 and a N/A. Then re-scanned and went to 3 codes P0304, P0316, & P0113
I removed the new MAF and rechecked the codes and am back to the N/A, P0304 & P0316.
My gut is telling me that maybe the MAF connection/plug is bad. But I don't know if I am game to try to unravel the covering and see where to splice in. I have not worked on auto electrical in over 35 years. Engine has been in this heat for 6 years, although garaged the past 3.5. Some things seem a little.brittle.
And we keep throwing money at it. Not sure if to throw another $50 for the connector on a hunch.
I am not sure what else it could be...fuel injectors etc I don't have those kind of tools or ways to test.
This vehicle had the Heads done 4 yrs ago, along with other (inflated) items for a $4K bill. (family medical emergency, so much going on to be able to see all that was getting done at the time.)

Any suggestions??? Other than give up?
16 y/o truck that only has about 78K miles on it, about 10K miles on the Heads.

 

Have a look at these pages, but don't start guessing and replacing stuff at random, it's also very unlikely a problem with the wiring.
If the wiring looks frayed or has had physical damage due to heat etc., then it's not the wiring.
Also, get yourself a compression tester and do that to take that off the table even if the heads have been replaced.
Fuel pressure gauges can be rented, should be above 55 psi. It will still run at 45 to 55, but not optimal.

https://www.ranger-forums.com/2-9l-3...-p0304-153837/

https://www.700r4transmissionhq.com/p0316-ford-ranger/

 

+1 to what Jeff's been saying

Especially compression test if possible, you really want to take that off the table FIRST, otherwise you really are wasting time and money on non-fixes for misfires
I think you are OK because you are getting "random misfire" codes, and only 1 #4 misfire code, but best to test compression first

3.0l Vulcan spark plug gap should be 0.044

DO NOT used the gap number on the emissions label, there were many with the wrong number
Also don't look at Ford 3.0l numbers they also include the 3.0l DOHC engine which had larger gap
0.044 use it

The early 2000's 3.0l Ranger coil packs were suspect, there was a "lot number" range but can't seem to find it any more, of coil packs to replace because of misfires

Also call local Ford dealer, and have them see if VIN needs a software update, there were glitches in 3.0l software that caused high idle and misfires

 

regapped plugs to .44 gas smell on one plug Battery recharged . Runs rough w misses.
Only code P0174 for the moment. Brought in for testing.
Upon testing O2 sensors good, Fuel trim on long term for bank 2 are up to 25 percent showing lean.
No Vacuum leaks.
compression teat on bank 2 :
Cylinder 4 110 psi Cylinder 6 155 psi

what do you think?

 

I think you have a burnt exhaust valve in #4, and thats causing a misfire which causes the Lean code

O2 sensors detect Oxygen in the exhaust not fuel
When a cylinder misfires no oxygen is used(burned up) so that oxygen is dumped into the exhaust manifold and O2 on that bank see that as LEAN, too much oxygen in exhaust

A cylinder holds compression via piston and rings and the Valves and seats
Ranger engines never had issues with pistons and rings, just not really ever an issue

But valve issues, on the other hand, are common on all 4-stroke engines, especially exhaust valves
Couple of things can happen
A valve needs rotate every time it opens and closes, this spreads out the heat so there are no hot spots, if rocker or valve stem gets a worn spot it can prevent this rotation
Valve heats up at one spot and starts to melt/burn

2004-2006 Ranger 3.0ls had a know issue with exhaust valve seats, they were under diameter and would shift lower into the head, this prevented the exhaust valve from sealing completely so lower compression and valve can start to get "burnt", eaten away, by combustion gases being pushed thru the gap between valve and seat
This is most likely issue, and BOTH heads would have to be changed, or machined with new exhaust valves and seats


Just FYI
Intake valves and seats are Cooled by incoming air/fuel mix, so rarely "burn", they can "tulip" if cylinder overheats but not at all common

 

Frustrating to have to do this again since heads were changed only 10k miles ago (4 yrs)
Thanks for confirming for me.

 

So who did the heads, were they new or from old stock with the soft valve problem ?
Or from an auto wrecker when Ford had the valve problem ?

It doesn't really matter at this point I suppose, I was just curious.

 

Done in respected shop,although they have since been sold. Believe they were new.

 

If the valve seat in #4 is in fact recessed, then they are not new.
It could be just a defective valve, you will know one the head(s) are off.

Can't do the job your self, it's not rocket science, it just takes some decent tools and a manual for the torque specs ?
Most of the stuff can be had from Rock Auto, like Fel-Pro gaskets and TTY head bolts.

That bill is bit odd, you were charged for a head gasket set, that should have had all the necessary gaskets to do the job, what are all those other gaskets ?

Rock Auto is out of stock.

https://www.summitracing.com/parts/fel-260-1997

EDIT:
Those other numbers are Ford part numbers, F2DZ 9439 A, I checked, it's the lower intake manifold gaskets, those should have been in the top end gasket set.
You were charged an additional 97 bucks just for those alone.

I realize that a garage can only guarantee their work if they use only Ford gaskets, but Fel-Pro are just as good or better.

 

Not much to be done now, 4 years later.
doing it myself not an option either.
Probably will look to sell it.

 

What was the reason, 4 years ago, that the heads were changed?

Its a long shot but maybe injector 4 was failing and causing Lean condition, which overheats that cylinder causing burnt valve, not a common issue at all, but certainly not unheard of either
You would have heard pinging/knocking under acceleration now and then, not sure if 2004 had a knock sensor

This is a sequential fuel injection engine type issue, carbs would burn ALL the exhaust valves at once if running Lean, but usually you would notice the Lean condition before that happened, lol

 

Not sure other than flashing CEL

 

Yes, correct

I was thinking of "why" new heads only lasted 10k miles, an underlying reason of why the original heads needed to be replaced but then new heads also failed, something in common, and thats the only thing that came to mind, injector

Yes, if you are not doing your own wrenching on this it may be best to sell it "as is", Mechanics special
Even if you did it yourself its still close to $800 in parts

 

My thoughts are the original TSB issue, was done incorrectly and here we are.¯\_(ツ)_/¯

 

No, they would have to have used "USED" 2004-2006 heads from a factory engine, so pretty slim odds they would do that

The TSB was because the 3.0l assembly plant got some under sized exhaust valve seats mixed in with correct size seats in 2003 and used them thru 2005, those engines went into 2004-2006 Rangers
It wasn't 100% failure rate, but high enough failure rate to warrant the TSB

 

Pick up truck prices vary quite a bit by area, check craigslists in different cities and you will see

Not sure what they are worth in AZ, best to check local craigslist for similar models with similar options and miles

Upsell it in description then you can add "sold as is" with a misfire and code P0304 if thats what it has
No need to mention any tests you have done or what you think it is, you are not a mechanic
Any used vehicle is a gamble at best

Something, anything really, is worth exactly what someone else will pay for it, not a penny more or less, lol

You can knock $500 off asking price of similar vehicles in your area to get some faster responses, its just an asking price