Hey y'all so I took my truck in finally to have a buzz test and contribution test done. My IDM and UVCH checked out fine. Contribution test #'s 4 and 8 were very low. I know #8 is always a crapshoot since it's the last to fire, but #4 has me concerned. I was told it was probably buildup, but no way of really telling until they pull the cover off and check the condition of the injectors. Ford mechanic said 100k is common for injector issues. My question to you guys is should I just replace the #4? Or should I say screw it and go with rebuilt Rosewoods (all 8)? Also wondering how long the process takes to get the injectors from Rosewood also since my truck is what makes me money I lose about $500.00 every day I don't have my truck. Thanks!

1996 f250 xlt 2wd auto 93,000 miles

 

Jims prices are great! And shipping doesn't take too long either. I'd go all 8 if funds were available to ya. Otherwise ya might end up like my buddy and do one at a time, one right after the other, until ya do all 8 over the course of a year.

 

I am doing all 8 while my engine is out...

 

If you really need to fix it, I'd go with all 8. To minimize the downtime you can order them from Rosewood in advance and send in your old ones for a core refund once the new ones are installed.

If it were going to cost me $500 day in lost revenue while the truck is down, I'd think two or three times about doing anything at all, unless you have other symptoms.

Since your truck is a money maker I suggest investing in your own AutoEnginuity scan tool. You'll be able to do your own buzz and cylinder contribution tests and won't be dependent on a dealer or shop for diagnostics. Not by any means an expert but I've found that cylinder contribution test results are iffy and inconsistent and I wouldn't replace any injectors just based on the results of one test.

Also, your truck only has 100k on it? Regardless of what your Ford mechanic says, that's pretty low mileage to be having injector issues.

So, there is my free internet advice, for what is is or isn't worth.

Bob

 

I would second that^

 

Yea I know it's crazy! But everything else has checked out. IDM, ICP, CPS, UVCH, and injector wiring all checked out fine. It smokes a little white smoke at startup, and the tach jumps once after it starts up. Idle is rough about 15 or so minutes until she's warm. Every mechanic said it is low mileage but that doesn't mean it's not injectors. I'm stumped myself because I'm about to drop 3,500 in new parts and labor for injectors and 17* hpop plus new GP's. I love my truck so I'm willing to do whatever it takes but so far it's been pointed out to me as being a mechanical issue, not electrical. I'm probably going to just bite the bullet on this and do it. I'll lose money yea but if it restores the life of my truck then money won't matter. 😄

 

You won't regret it, my truck has a ton of miles and was beat to death, but slowly Ive been fixing it to my liking and it keep getting better and better

 

Could just need injector o-rings. I have seen too many of these trucks with 300,000 + miles running on the original injectors to say they would need replaced at 100,000.

 

Could air in the fuel lines cause these symptoms also? I just started thinking about that.

 

No air on the regulated return unless you have a crack somewhere, but that would affect all of the injectors, not just one or two. And yes, replace all. You'll be glad you did.

 

It could be be something as simple as a couple of bad glow plugs. That would account for the smoke at startup since one or more cylinders wouldn't be firing efficiently or firing at all. It would also account for the rough idle until the motor warms up and starts clicking on all 8.

How does it run when it's warmed up and rolling down the highway? Has the fuel mileage gone down? Is this warmup problem affecting it at all when you're out working with it?

Here is something I learned, not sure if it has any real value. I ran a buzz test on mine earlier this year. I think I ran two buzz tests, to make sure. I noticed that after the tests my truck started very noticeably faster and it still starts faster than it did. Someone here pointed out that a buzz test can shake injector deposits loose. Someone also pointed out that repetitive buzz tests might not be so good for injectors since they would be vibrating while dry.

Also, I think you mentioned in another thread that your mechanic said that the water in fuel light came on? A lot of planes have crashed because the pilot didn't believe his instruments. Did the fuel bowl get drained and cleaned?

$3500 is a big chunk of change, especially with the holiday season upon us. It's real easy for me to get too involved in working on my truck and lose the big picture. If this were my truck and this problem isn't affecting it once it's warmed up and being used I think I'd try to step back and let it go for awhile and maybe get a different perspective on it.

Bob

 

The truck still idles a little rough even after warmed up. And now at every cold start my engine will jump up once after it starts. Also the fuel filter light is on yea. It was changed about 2 months ago. I don't believe it was cleaned out or drained the fuel in the bowl looked great and the filter wasn't all that dirty.

 

What should the cost be to replace o-rings?

 

Alliant Injector O-rings - Ford 7.3L Powerstroke (94-03)

There ya go.