Hi all, I've got a stumper that's running me ragged.

>Triton V10

It's possible your spark plug holes are fucked, that thing is notorious for shooting them out or having fucked up threads.

>>15720115
I thought bad o2 sensors always went rich. But I'm just a benchracer. I hear those V10s are awful and I just saw a new F550 Penske truck or some bullshit with the badge today. Didn't even know they made those anymore when the obvious choice is just a diesel.

Bad injector.
Replace cylinder 3 injector, replace all plugs.
I dealt with this exact issue just 2 weeks ago on an F-150.

It 100% has an obd2 port.
No firing on the entire right side? maybe timing is kill, do a compression check.
The COPs do die, it doesn't matter if they are ohming right, they are dead. It's a Ford thing.

>>15720128
No, grandfather does VW beetles so we're familiar with helicoils and fucked plug holes. He swears the threads are perfect and were antisiezed
>>15720146
That's what I said. I know the chain guides go kill.

>>15720128
That's on the 3v heads, a 00 won't have that

>>15720143
To carry on. Test cyl 1, 2, 4, 5, 6, 7, 8, 9, and/or 10 injector for ohms. Test cylinder 3. If c3 reads way different or 0 its a bad injector.

I'm thinking you might need a dummy plug, but besides that have him triple check the plugs and injectors.

>>15720199
Sorry I meant dummy o2 sensor

Small update
To quote

"It idles fine but as soon as you touch the gas it starts stumbling real bad like, maybe a CPS partial fail?"

I don't see how it could idle well with timing out.

>>15720115

I'm assuming its a custom body+cab on a Ford frame, which I'm sure makes things 10x as complicated. It WILL have an OBDII port, but knowing what these installers are like, its probably located right next to the shitter pipe.

>>15720211

Is it possible that its simply not getting fuel to the cylinders? Or at least enough to have equal combustion. I'd verify that its getting spark to the bad cylinders and then test to make sure they get fuel too.

>>15720115

>Removed, gutted and reinstalled cat

Correct me if I'm wrong OP but don't most newer cars have O2 sensors before and after the cat?

No wonder it runs like shit if you just put a hollow cat back in it

I'd ask here as there are a shitload of Ford techs who post frequently.

Here's the V10 section:

http://www.ford-trucks.com/forums/forum49/

I've used the resistor trick when gutting cats on the smaller Fords of that engine family for many years and zero issues. (I do the soldering on the bench after harvesting the pigtail from the secondary sensors.)

I'd go at the coils with an ohm meter.

Call me retarded, never owned a big ol Ford but not burning the gas you have and not having enough gas will be similar

>>15720373
Second o2 should just be for checking cat efficiency, not compensation in engine parameters. I think. Sounds like a stuck open or sticky injector or spark issue, since extra unburned fuel would cause the cat to go red.

>>15720115
leaking intake gasket causing it to run lean by getting unmetered air. were the plugs white?