1999 f150 4.2l v6 4x2 130,000 miles. No power under load.
History: oil changes every 5k, plugs every 30k, wires @60k and 110k, fuel pump replaced @ 90k, new frame @ 60k, dark odometer solder fix @ 100k. This truck has purred along until...
What Happened: the positive lead from battery to the starter came in contact with the hot EGR cross-over tube, arced and burned a quarter sized hole in the cross-over tube near the #3 cylinder.
I disconnected the battery and added fuel stabilizer to the ½ tank of gas and then the truck then sat for eight months.
Repairs:
1. Replaced the routing bracket for the lead to the starter and the lead.
2. Repaired the cross-over tube, replacement is only available for V-8's and 10's..
3. Changed plugs and wires (1,2,3 5,6,4).
4. Cleaned/lubed IAC and EGR valve.
5. Cleaned throttle body and EGR differential feedback sensor.
6. Changed the oil and filter and air filter.
7. Checked vacuum hoses, wires, fuses, ect. in prep for CA smog check.

The truck starts and idles fine . All cylinders contribute and I have verified spark on all cylinders at idle. Low load or cruising acts fine, under moderate load, hills, quick acceleration, acts and sounds like only five cylinders are firing. No codes or check lights, and the full drive cycle has been completed. I don't know where to check next. Any help is appreciated.

 

Well one easy check i would do is the injectors. Maybe one is alittle sticky after sitting for a wile and when u demand more fuel the injector is only putting out what it can vs what it needs and giving u a slight miss fire that wont throw a code. Or maybe that injector was on its way out and when that Hot wore arced it was just enough to tweak that injector. So id just do a ohms check on them all and see which one reads different the rest

 

Did you run out the old gas and put fresh gas in?
Next is to use a Scanner to look at live data for something out of spec.
Otherwise it's all just guessing.
Good luck.

 

Thanks Dutter 2. I grew up a carb guy, so I never even thought about injectors. It makes since that they might be the culprit at 130k. Do you know of a good instructional for getting at the fuel rail and injectors? I might just go ahead and pull them and send them to MrInjector for a cleaning.

 

Bluegrass 7, I haven't run the old gas out yet. I'm going to add some Berryman's 2616 since the tank is still half full, the run it out and top with fresh fuel tomorrow. I wish I could just dump it down the gopher holes in the yard, but that wouldn't be very sporting of me, would it?

 

My comment is you can't make good gas out of old gas with additives.
Berryman is a cleaner.
At this point you should open the fuel system at the filter and pump good fuel through to that point, change the filter, then what is left in the line to the injectors is what is left to handle.
Also additives change the makeup of the fuel.
Ox sensors detect this and shift the fuel tables trying to compensate.
A vehicle left that long is often bad news as your experiencing without running it down on fuel to minimize the old gas results when it's time to fire it up again.
Good luck.

 

yep i get were ur coming from then, yeah just think of it like a sticky float or needle.. And sorry to say there really isnt much of one. Its just how ever you can get to them and take off the connector and hook up your multi meter leads to the prongs on the injector, i got some long fancy leads that help me. And you dont really have to know the exact rang of resistance they have to be in. All you have to do is see which injector has the odd reading. Like 7 injectors read 16 ohm and one reads 5 or 20 ohms, theres ur problem. But if its hard to tell then yes get the exact ohms rang.

 

Point well taken. My thought process was not to solve the problem with soap, rather that running the gas through the engine would likely foul things more, adding Berryman's and running the gas through might knock some of the gunk off and Not that I could fix things with a canned mechanic. When I start with a new tank, and a cleared and refreshed ECM, the problems that remain are more likely to throw a code to help with diagnostics. And I don't have to worry with disposal of the bad gas.

 

You might consider looking at it this way, If you have no misfires, the injectors nor ignition are not the cause of a large drop in power.
Old gas is a formulated mix of cracked gas, chemicals and Ethanol.
The lighter parts of the mix separate and evaporate out.
This leaves a gel like heavy part behind and permanently alters the gas for it's intended use..
The BTU content is not there to support much power from combustion.
Additives certainly add to what is left so you can't predict what the results will be.
.
Power equipment for Lawn and Garden are very subject to this end result if left at end of use until the next year the equipment is used.
I do use Berryman in the gas and PBS Blaster intake spray on these small engines. I saw it do an amazing job within about 3 minutes of starting the motor on fresh gas.
How this was seen is the motor has a carb that is non adjustable. The fixed air bleeds were plugged up with evaporated fuel leaving the heavy part. What happens with this situation is the carb meters fuel too rich or in excess, making the motor 'put put' under load because a basic air carb meters more and more fuel not in proportion to the airflow, but more as airflow increases hence the use of air bleed channels to keep the ratio more constant with the airflow.
The additive and spray mentioned dissolved this within minutes. The makers/ marketing knows this works on small engines.
In auto uses you don't have quite the same access to get this result. That would be to easy.
Clean the tank, put fresh gas in, then some 'limited' amount of cleaner.
And you still don't know if there are additional issue to be solved for but address what you do have first..
Good luck.

 

Well... ... Crud. Now I am convinced that I will need to drop the tank anyway, just to be sure. A "How to" on cleaning the fuel rail anyone?
Thank you Bluegrass

 

Found this on F150onlie forums Thanks to RoscoeT , now hosted in my dropbox until I need the space.
https://dl.dropboxusercontent.com/u/...-2003_1231.zip

 

Oh just throwing this out there dont over look the FuEL FILTER once u clean the tank out, Dont know if someone brought that up already but just wanted to be sure. Because im sure shes all clogged up will give u problems. Hell maybe try that first because its easy

 

And cheap.

 

Update:
Fuel tank dropped and cleaned. New fuel filter. Full tank of fresh gas. Coils check at 13.5k 13.3k 13.4k and all signal to ground .00ish. Plugs are Autolite Iridium Spark at all plugs. Drive cycle test: Idle smooth. 1000-1300 rpm at speed smooth. Hesitation and stutter under light throttle with ?less? power at 1500 rpm than at 1300. Still gets to 45. Higher rpms 3000+ smooths out but still lacks power. cruising at 45 mph is 1000rpm. getting to 55-60 on any grade requires 4500-5000 rpm to get there. 4th speed up/slow to 45, just making 45 the check engine light flashes until it slows to 45. U-turn back to home and once more to 55 and the light flashes again. 40 mph back home with 1200 rpm cruising and no hard acceleration. 25 miles total and close to 1/4 tank of gas.
Finally, 2 codes, P0300 and P0303. Random misfire and #3 cylinder misfire.
I pulled and checked all the plugs, all clean porcelain and black at the threads. #3 cylinder had oil on the threads of the plug, the others were clean.

Guessing my next is to do a compression test and check the injectors. The way ford hid the fuel rail, I feel I need to pull the upper intake to get at them. Any suggestions on what to do first?

 

Ok to check compression but based on your report of smooth idle, that cylinder was not misfiring before the code set.
Resistance check of the coils is not all inclusive. If a coil has shorted turns not just shorted you won't pick that up with a normal resistance check, so keep that in mind. A few turns shorted kills the ability to produce max voltage during high air fuel ratios when it's needed the most.
At this time, your Scanner live data looking at all the parameters should show up something. It almost has to.
I would want to look at what the ignition timing is doing during acceleration for one.
Next at mode 6 test 53 misfire monitors to see if it is a general ignition or just a single cylinder issue.
Your certainly getting an education by going through chasing these troubles.
It's an example of not letting any vehicle set a long time without prepping for it.
Good luck.