7.3L Faulty Injectors Out-Of-Box
As a Ford dealership technician, I would like to share an experience (or nightmare) with you 7.3L owners that I hope will "open your eyes" a little bit. I'm sure most of you are aware of Ford's FSA 07S57 CMP sensor replacement recall.
Well, just at the end of last month, a 2000 F-350 tow truck darkened my doorstep in for his 07S57. This vehicle has 745,000 kms. (approx. 423,000 miles) on it. It was business as usual. I brought the vehicle into my bay, changed the sensor and the owner went on his merry way.
About two weeks later, my dealership receives a phone call from the owner of this vehicle complaining that "ever since you guys replaced the cam sensor this thing has been running rough, and now it will barely run". The typical "ever since you did THIS, my car now does THAT......yada yada yada" that us mechanics have to listen to all the time.
A day later, the vehicle arrives on a flatbad (from the same company) waiting for my diagnosis. I manage to "limp" the truck into my bay and run some self-tests that very quickly determine that cylinder #4 is not pulling its weight. At this point is where I now inform the advisor that this guy now owes me my diag time, and the cost to replace cylinder #4 injector with labour if he chooses to repair it. Reluctantly, he agrees to the repair. Once the job is said and done, everything appears golden. I rerun the injector buzz self-test, and all eight are working once again. I road test it around the block with no problems. I even cold start the vehicle the next morning, before the vehicle is released with no problems.
Fast forward to the next weekend and my boss gets a phone call from the owner again. Now, he's a little pissed (and I don't blame him) that when he picked up his truck, he claims the truck started doing the same thing AGAIN! So, in rolls this vehicle back on the flatbed. I finally get to it on Monday, and low and behold, it sets another hard P0270/P1274 DTCs (cylinder #4 injector low side circuit open/shorted). At this point, I'm thinking in my mind, okay this truck has a bad-out-of-box injector. So off I go to order another injector for this truck, and in the mean time I check and double check, and triple check the cylinder #4 injector low side circuit. All checks out good. "New" injector number 2 arrives and I go to test it, and P0270/P1274 sets AGAIN.
Now, at this point I'm wondering if there was a misdiagnosis on my part. I'm human just like everyone else. So, off I go to order an IDM (I don't have a "tester") to plug into for "testing" purposes until I can determine the problem conclusively. At this point, after exhausting all possible avenues to isolate a problem in the wiring, I consult with Ford Hotline to see if they can be of some assistance. After trying some load tests (powering up a sealed beam headlight bulb through the injector #4 high and low side wiring), it still indicates wiring to be good. I even test an adjacent non-problem cylinder only to achieve the same results! Now I'm getting desperate, and I overlay my own wiring directly from the IDM to the injector, STILL P0270/P1274 does not go away. At this point, Hotline's last "suggestion" to me, is to replace the entire wiring harness. In other words, tell the customer he needs to spend $2400 on a wiring harness PLUS MY LABOUR to install it, EVEN THOUGH IT HAS BEEN TESTED GOOD.
Here is where I am now ready to "throw in the towel". The two DTCs are a very straightforward problem. It either comes back to the injector, wiring or the IDM. Both the IDM and wiring have been tested, and tested, and tested, and tested GOOD. What are the chances of having TWO bad-out-of-box injectors? Well, at this point I'm willing to try just about anything. I "borrow" two 7.3L injector core returns from the parts department to retest. One happens to be the original core from the first injector I replaced. It fails (no surprise there). I then proceed to test the second core return (from a parts over-the-counter sale to another shop) and what do you know? IT PASSES!
Okay, after much discussion with my boss and the parts manager, I finally convince them to get me yet another injector. The third injector arrives and it passes!!! I guess the third time is the charm, right? So, I quickly reassemble the vehicle back to its original form, and retest (yet again) with the injector installed and connected to the original wiring and IDM, and low and behold it passes!!! At this point, is when I get the service advisor to authorize for me to drive the vehicle home for the evening. This way, the customer can't accuse me of releasing the vehicle to him with a problem still present.
The next day on my way back to work (and 80 kms. or 50 miles later), the vehicle still runs smoothly, and P0270/P1274 DOES NOT RETURN!!! Now comes the interesting question. How am I going to get paid for this mess that obviously was NOT my fault?
Last edited by m-chan68; 04-10-2009 at 10:59 AM.