Injector #8 failed Cont. test

[cpayne6335]

Hey,

Today I did a buzz test on a cyl. Cont. test. Buzz test passed, and all injectors sounded the same. Then I ran a cyl cont test, and the TE scanner said the test would last 4 minutes, and only lasted about 1 min, and thena screen came up and said Cyl. 8 failed. The main mechanic at the shop said Cyl. 8 fails most of the time, and it may not be a big deal. I can not hear a missfiring.

another problem is blow by. I see some smoke coming out of my oil fill tube when I add oil when it is running. I also get enough smoke while at a stop, I can see it coming out from my wheel well. I did move the CCV tube to dump under the driver side leaf spring.

No related codes came up. I am still wondering about MPG. I just got 13.2 MPG. Not sure if that is good for a 99.5 CC LB 4x4 dually auto truck that wieghs close to 10k. gears are 4.10 Stock for the most part.

Thanks for the help...

[dray8165]

Cylinder 8 fires immediately after 6, which is on the same bank. Because of that, the pressure in the high pressure oil rail is less than when the other cylinders fire. Ford changed the injector type in that cylinder to an AE (you have all AD's) later to address this problem. Remember the old adage, "If it ain't broke, don't fix it"

The 7.3 has a passive crankcase ventilation. The blow-by normally enters the cold air intake and is burned - since you routed it under yor driver's side leaf spring - you're going to get to see and smell all your blow-by. It is normal. Most people route the vent back behind the cab so they don't have to smell it all the time.

13.2 in a 4x4 dually with 4.10 gears isn't bad. You could probably get 15 or 16 if you bought a ScanGauge II and watched the instant MPG's while you adjusted your driving habits to maximize your mileage. I can milk 19 out of my 2wd, F-250

[cpayne6335]

well, I took off the oil filler cap, and it did not build any presure to blow off the cap. for giggles, I found a a plasit cup that would seal the tube, and it did not come off, so there is no presure with the blowby.

I am just trying to get everything working on the truck before I leave for 5 months for Basic training and AIT. My wife said she will drive it a few times week to keep the seals good. It will be about a 12 mile to her work and 12 back. I do not see her driving it much more than that.

Is there any easy fixes for the #8 injector? Like a regulated fuel return or get the shim kit, AKA BB mod. I know the BB will not work on my truck.

Thanks for the replies. I guess for the MPG, I need to chip it to see any more gains, but funds are too tight at this time, and reading about all the windowed blocks kinda scares me about chiping it. But when I get the cash on hand to get one, then i will call the tuners and ask questions.

[dray8165]

Originally Posted by cpayne6335

Is there any easy fixes for the #8 injector? Like a regulated fuel return or get the shim kit, AKA BB mod. I know the BB will not work on my truck.

Thanks for the replies. I guess for the MPG, I need to chip it to see any more gains, but funds are too tight at this time, and reading about all the windowed blocks kinda scares me about chiping it. But when I get the cash on hand to get one, then i will call the tuners and ask questions.

The problem isn't fuel pressure - its oil presure in the high pressure oil rail. You could try the high pressure oil crossover modification - I would recommend going with the solid pipe as opposed to a hose. You could pull and replace injector 8 with an AE injector. Otherwise - just ignore it. It went this long without giving you a problem - the only "problem" is the scan result.

I predict that if your wife starts driving your truck that you may never get it back

As for a "chip" - you can have Jody at DP Tuner burn your PCM for 75 bucks. You get to pick which "tune" you want.

[cpayne6335]

For the crossover line, I have one on. On the driver side, it is in the very back port, and same for the pass side port. do I need to bleed the air out for it to work correctly? The line has been on for about 4k miles.

For my wife, she has already taken out the truck once, and hates it. It was too big and long!!!!!! Plus it was too hard for her to get the kids in and out of, so I hope she does not grow a liking to it. She hated my old f150 and only got in it once in 3 years I had it!!! she has been in the f-350 3 times since Ihave owned it for less than a year. I just keep it dirty, so she stays away!!!

Sounds like I just need to drive it and leave it alone for now. The truck runs good, sounds better (since I cut off the muffler), and fix the other small things wrong with it.

Thanks again for the replies guys, I just want my truck to last another 200k for me, I am ready to hit 253k. I am the third owner. First owner had it for 36k, 2nd owner sold it to me with 243k. Other than basic oil changes, the 2nd owner put breaks, alt, GP's and shocks on it. I have done the starter, alt, IPC and some relays. Still orginal injectors HPOP and trans!!! She is still my work in progress.

[dray8165]

No need to bleed the air out - it works itself out pretty quickly. Sounds like you've got it all figured out. Best of luck on your deployment. Thanks for your service. Just remember, when they shout "duck" in the army, you're not supposed to look up for a flock of birds.