Tmulls1995

the first shop found a bad injector after I had replaced all 8, but one showed up to my house already broken and they found another one gone bad on the truck itself so they charged me for that and fixing an issue I've been having on and off with tail lights not working. 2nd shop didn't charge me anything even when I offered to pay them a little just for the intake gasket. For shops I'm only down like $4-500 but with parts I'm down about 2x that at least

1FastBrick

iTrader: (17)

I don't recall any good compression gauge ever saying "Normal" . Normal is not a specification... LOL

If they have changed all the parts that you stated above and you have the correct fuel pressure. I would suspect a mechanical issue.

Did they Physically have the heads off?

Tmulls1995

Both shop stated that "all valves, springs, lifters and rocker arms are in excellent condition" and that the cam lobes are less than 1/5000th of an inch off, and assured me that for 150k on the truck, that's really good. 1st shop did say that a valve guide or seat may be bad and it doesn't get picked up on any sort of testing, then said they dont replace heads because head gasket liability and stuff. The 2nd shop wants to charge $1500 just to pop the heads off and check the everything on the bottom side of them... which I may end up doing myself honestly.

If a guide or something is bad when I pop the heads off then I'll get it fixed and re install the heads but with the help of a pro to make sure I'm torquing them down correctly.

1FastBrick

iTrader: (17)

I haven't seen a bad powder metal guide on one of these engines unless the valve was bent or something went Kaboom.

I suspect it would have to of been run with out oil or with really contaminated oil to damage a guide on these.

Tmulls1995

Problem is .. I adamantly take care of this truck. It's original paint, wheels, body, everything besides the headers and muffler. Bought it with 124k on it and barely any scratches or rust on it. I've taken the best car I could of this thing. Oil change every 3k, kept tranny and coolant topped up, checked oil every other week and it never burned hardly any. I'd put the 5.5qt in it every oil change, and when 3k was up I'd still have little over 5qt in the truck. Oil pressure has always been at 55-60psi at idle even when its hot.... unless somehow an air bubble got caught but I dont have any idea how that could happen. The issue started one day on my way to the tech college I attend, I came to a stop at a light and noticed the wobble. It's been parked for the last 75 out of 90 days at least

1FastBrick

iTrader: (17)

I don't see the guide causing the issue.

bottledls6

iTrader: (2)

Have you considered a leak down test? Sounds like those shops don't want to get to heavy into this truck or your truck is pushing their knowledge of auto mechanics. lol question. what heads are on your truck? If this was me, I would do a leak down test, that will help you if you have any mechanical damage, Id check the fuel rails for debris just for ***** an giggles. ( seen it before) After that id start looking at the harness. You can always do the good old Ford wire wiggle test while its running see if anything changes. If that don't do anything maybe start looking at getting a new harness or chasing wires down. By no means am I saying any of this is the issue, kinda just spit balling ideas off of what I read. Maybe see if you have any vaccum leaks. ALSO I would do your own compression test, I feel like they didn't really do one, they just told you that to get you gone. I have chased my tail before after someone said they "DID" something an they really didn't.

Tmulls1995

its had multiple leak down tests, none of them came back showing any problems. Both shops and all mechanics said the leak down test went perfectly and didn't signify any sort of issues. I've done vacuum leaks myself and couldn't find any, and the shops also did many vacuum tests. I took the fuel rails off myself and made sure they were cleaned out when I did the injectors, so they should still be clean. The fuze block and wiring harness is all that's left, like was stated by someone else previously. I suck with wires n **** tho, so I may buy the harness and block and take it to another shop to install it

1FastBrick

iTrader: (17)

Where are you located?

Have you physically pulled the number 5 and 6 plug and wire and tested it to see if its firing?

What codes does it set?

Tmulls1995

I cant remember the specific code off the top of my head, but they are specific to those cylinders. I have tested the plugs, wires, and coil packs and then the shops did as well. Randomized all injectors and ignition components multiple times and problem persisted on 5 and 6