Cylinder contribution test shows an issue with the number 3 cylinder. Engine has just over 150k on it, no previous issues other than normal worn out parts replaced. Engine starts fine, no hesitation, no power issues, no mileage drop that I can tell. Oil and filter changes have been around the 5k mark, mostly Rotella some Amsoil. Fuel bowl had to be rebuilt a few years ago to replace leaky o-rings and fuel filter has been replaced about every 25k or so.

I am making the assumption that the injector is starting to give up or has an issue. So, my take is that it's parts buying time. Besides a set of injectors and valve cover gaskets - what other hardware should I accumulate and replace while I have it apart?

 

I believe that number 3 and 8 are common failures during the CCT and this should not be considered a bullseye of what is wrong. You can search a bit to determine if I have made my first mistake of the day in telling you this, but I "think" that is right...

I read your post, but did not see any real problem descriptions. Were you running a CCT just to learn about the engine and familiarize yourself with it? If so, good on you!

Monitor things like ICP, IPR DC, FUELPW, RPM, MPH, TFT, EOT, etc... Once you get a good baseline of how the truck normally runs you can get right to the resolution if/when a problem arises.

 

Well, I had #8 initially about 2 months ago when I ran ForScan just to get a baseline on the engine. ( I also have a V-10 RV that I keep track of and now I have some questions regarding that information.)

Anyway, I did a couple of treatments with a Diesel Injector treatment in the fuel and I also found out that that the #8 on these engines can be a "ghost code". I now have the 8 and the 3 showing up so was thinking maybe I'm going downhill here a bit which led to my post. I'm retired and no way I could ever afford another truck so I have to keep this one running. I ordered this truck and took delivery of it November 4, 1999 as a 2000 model. It is a RWD Dualie, Crew Cab w/ 8 foot bed. My next moves are just some early maintenance with a fresh oil and filter change along with the fuel filter. I was also considering a dose of Archoil which I have heard is good stuff for the injectors. I also need to service the trans fluid and filters at the same time. Last fall I rebuilt the entire front end after I had an upper ball joint going away. And there is no performance issues with the engine - I just want to keep it that way.

Thanks for the post, information is always a good thing.

 

I've also remember reading about the #3 ghost code. Pretty sure the claimed cause was a result of grey CPS. Couldn't, wouldn't, shouldn't say that's your issue. If you read enough threads you find that the CPS can cure everything short of the COLD. Lost my gas cap, better swap the CPS. To me it sounds like you have a good running well maintained truck. I wouldn't get too worked up about a CCT with no other symptoms. Personally I don't put much stock in that test for over all diagnostics. If you have a performance issue it can, and I say that very loosely. can help narrow it down to which cylinder.But if you find out you your o-rings or injectors are due are just going to change the one? I'm not, they're all getting changed.

 

So part of the reason for the not so good CCT results for #8 and #3 are due to the fuel system layout and the firing order. The fuel enters the drivers side head from the front, while the pass side is fed from the rear. It's a closed system as well. #8 fires right after #6, so there's a potential for a lower fuel pressure to fill the injector. Same goes for #3 which fires right after #7. But it was bad enough for #8 that Ford had a replacement injector for the position, which became standard at some point. Called a "long lead" or LL. I'm not entirely sure what was changed, but apparently it was a fix. If it wasn't standard on your truck, and you didn't complain about it, then you don't have a LL injector in #8. Which makes me wonder whether Ford is still honoring that TSB.
Another option is for you to install a Regulated Return, which isn't difficult and not too pricey. I have one and I haven't had any issues with it, but I'm not all that certain I really needed it on a stock engine that hardly sees any big loads where fuel pressure consistency is absolutely needed.
If anything, electrical connections and wiring under the hood are simply degrading with age, sensors are getting old, exhaust back pressure tube is clogged. All the things that are now bad on my truck ..

 

Almost forgot, original owner 2000 PSD with 150k? We want pics !!

 

If you are happy with it,just keep it going!

LL injectors in ADs or ABs has 0.1mm shorter intensifier piston.
If my math is correct,AE and AF injectors pushes around 3,33cc more fuel.

 

Thanks to each of you for the input - maybe I'll just run a test as part of its maintenance and keep an eye on it.

Last night I was looking at the ForScan tests again - there's another series of monitors, one for each cylinder, if I am reading internet information correctly, these tests relate to injector function?

 

PERDELS are the quantitative test of cylinder performance. You’ll see higher numbers on 3&8. Make a note of these percentages for future comparison.

#3 and 8 often fail CCT and are not indicative of a problem. I do not advise changing anything.

 

Have to admit, I am starting to wonder about the software. I put the latest copy on a newer laptop and sat with the truck for about 30 minutes running different tests. I watched those PERDELS and you're certainly correct most of the numbers reported are in the lower range, 3 & 8 were higher and I also had 3 cylinders that had zeros, never showed anything. I also looked at CPS status - good, water and trans temps - all good. I am still learning my way around the software but I don't see how I could screw up the PERDELS when the other 5 were providing results. I am going to look again today to make sure and see if I can't record it this time. I spent a good part of yesterday cutting up knocked down trees and was kinda shot.

 

If I understand correctly - ‘Perdels’ is a measure of deviation of each cylinder and uses the CPS to measure the time between each combustion event. More time = less contribution.

You want zeroes or a fraction of a percent. I want to say 5% will trigger a failed CCT, but in my experience you don’t feel a ‘miss’ until closer to 10%.

3&8 commonly fail CCT and produce higher perdels on trucks that run perfectly fine for years and years. Many have changed these injectors to find the same results. As mentioned, this has to do with the firing order and the way the CPS measures data.

I have bought trucks and engines that ‘mechanics’ told people had poor compression because they had no idea what CCT actually was. If engine does not have blowby, I’ll swap a couple of injectors around and if problem follows - replace injectors for a perfectly good running truck again.

I have given many of my non-local customers a ScanGauge2 over the years. I always ask them to study what they see for awhile and only call me if the truck is not running good. Invariably, when given a LOT of new data - people get concerned - even if there is no ‘problem’. I tell them that tool is for me to be able to help them diagnose a problem remotely and not for them to have extra stuff to WORRY about.

 

Take a pic or record (data log) the perdels you see now and compare this to future tests.

You may be able to see a gradual increase as injectors wear.

Fuel and oil additives rarely have any effect - in spite of the fantastic claims on the bottles and great reviews by the gullible......