Heres one , not the one I'm looking for. I 'm still looking - will add to this as I find ..

https://www.f150online.com/forums/sh...ac+accumulator


Here you go , this is a good one - read more than just the first post ..It gets explained further on as things develope - Quite a few people get involved. Mileage and performance increase just by isolating the the two magnetic fields from one another..

https://www.f150online.com/forums/sh...1&page=1&pp=15

This should be a sticky..

 

thanks Jbrew ill take a look 2morro. how was ur X-mas party??

 

It's worth a look, maybe two..



Party? It was ok - left early if that tells yuh anything

 

that sucks but yeah been thinkin alot about this prob. and well thinking is not the best thing for me lol. gonna take off the o2 sim's and clean um up and everything. and resest the computer again. look at that been A/c can 2 morro. if that dont fix it you still got a job for after X-mas n new years. lol good way to start the new year with a nice side job for ya! ill have a compression test done by then. ill post the compression numbers up here when i get them. you should come out here for X-mas were having prime rib...UMMM YUMMY! i < 3 prime rib!

 

Did a compression test. Cyl 1 *misfiring cly* 140 PSI cyl 2 132PSI Cyl 3 135PSI cyl4 129 PSI. Cyl 5 137PSI cyl 6 141PSI Cyl 7 137PSI Cyl 8 130 PSI. After that i took an injector from my extra parts put it on. The truck seemed to run fine then all of the sudden the misfire was back. New coil packs. new wires *even tryed swaping back to Stock* The misfire isnt there almost at all in park or at cruiseing. but from a dead stop my truck shakes and has no power. So the PSI is fine there is no pinging or knocking. The spark is fine new coil packs. and i swaped the injector....what is left that would cause One cyl to misfire??

 

Did the compression gauge behave the exact same way in each cylinder or did it take longer to pump up to full pressure in some cylinders? There's more to a compression test than just the end reading.

 

check your fuel pressure too...

 

A bent valve stem will not cause a noise. When a follower comes off it will usually bend the valve stem only, not the valve face. So the valve is still seated in place and will show good compression and leakdown, if it is an exhaust valve. An intake follower off will show low compression because with the intake valve stuck closed no air can be pulled into the chamber to compress. This is because the valve will not operate as the follower no longer is in the picture to move the valve.The follower is laying in the cyl head somewhere doing nothing. I'm not certain this is the problem with your missfire but I have seen this condition on many dealer returns over the years. This is one reason a compression and leakdown test is not always the gold standard for an overhead cam engine. Another problem with a compression test is that usually a dead cyl is one that has raw gas or oil in it and will give you a wet compression test as opposed to the other cyls in your engine that may be running fine. They would have a dry compression reading. A wet test seals the rings better and tends to give higher readings. I still think you should remove the cam cover and check things out but thats your call. Good luck.

 

Shifty 85, maybe this has been addressed, but how do you know it's cyl 1 that has a mis-fire? If you know exactly which one is mis-firing, what color is the ceramic insulator of the sparkplug?

 

i know its Cyl 1 because thats what the CEL says. all of my spark plugs look the same. Grayish ground. white porcelain. i think im going to pull the valve cover off and watch the springs and make sure everything is doing what it should. i check fuses and all of that. i moved the wire from the a/c Can no diff. what i dont understand is. when i frist put that injector in it worked fine drove around i could Feel all 8 cyl's were happy then after about 5 mins the miss returned. Also i dont know if this is a good test or not but i took off my Air filter while it and coverd half of my intake tube and the idle didnt chage i coverd almost all of the intake tube and it didnt make a diff. in idle. bad MAF? if this was a valve prob wouldnt it always be there no matter what i chaged? and would the CEL be on for the valve reading as a Misfire? Sorry for all the question i just dont know whats going on!

 

well just made an 80 mile trip. my truck is almost moody. it will run great for 5-10 mins then run like crap for the next 5-10 and it keeps repeating that pattern. im on winter break so ill prob pull the valve cover and see whats going on under there.

 

Just my opinion but cams, springs and valves are not usually moody. They are mechanical in nature, they either work or they don't work. The mechanical things that cause problems can show variability with RPM and temperature, but from the comments stated I would lean more toward a fuel or electrical, PCM symptom, which are a litttle more random.

 

Sounds like a fuel filter or the pump - #1 is the furthest away. Shifty, after you had the code read and found out it was #1 - Then you pulled #1 plug . Was it wet? I seem to remember that it really wasn't.

I think built54 suggested testing the fuel pressure. At this point , I would throw a fuel filter on it and see what happens. If the problem persists , check the pump and regulator..

Eliminate those things first before anything else .

Merry Christmas :santa:

 

did a fuel filter not to long ago. ill check fuel pressure. Merry christmas to you guys too!...hope santa got me a Diesel!! lol. i know the pump is in the tank...how do i check that? Thanks alot guys i really mean it if i didnt have this site i woulda taken my truck out back and used my 12 Ga Merry X-mas!!

 

I would change it again - You test pressure at the rail by #3 - That 's Haynes book has that all mapped out pretty good .

I doesn't matter if you changed the filter in it last week , I would change it again before buying a fuel pump ..

I just change the filter first if there's any chance a problem may be fuel related - It's easy , cheap and could save you allot of time..

You can test the pump first if that how you want to do it , you may have good pressure - it's possible..