Diesel injectors

[76S&S]

I went to crank my F350 7.3 dually this evening and it will barely run. Can anyone tell me how to check the injectors to see if I have a bad one or do I have to put it on a computer?

Woe is me....

[dog paw]

Definently get it hooked up to some diagnostic equipment. Way too many possibilities to take pot shots at. Hopefully its something cheap and simple like a cam sensor...They were a weak spot on 7.3's

[Cloaked]

That 7.3 should not have injector problems, generally speaking. Look to a dirty fuel filter first. However diagnostics tool is your best guess after a filter change.

[TayMC197]

Glow plugs! That 7.3 is old, it's cold. Glow plugs fail and creates that symptom. Let me know more about exactly it's doing.. Might be able to help you better.

[Ben]

Originally Posted by dog paw

Definently get it hooked up to some diagnostic equipment. Way too many possibilities to take pot shots at. Hopefully its something cheap and simple like a cam sensor...They were a weak spot on 7.3's

This went out on mine at about 160k. This was a while ago. It was covered under a recall if I remember right. I also put in a new glow plug relay. Got it at international dealer, much cheaper.

Good luck.

[jschildm]

If its glow plugs it will start hard, but once it is started, run just fine. If it starts and still runs like chit for an extended period of time, then there is something else wrong. Cam Position Sensor is a weak spot on them. If you have someone with a scan gauge or auto enginuity, then you could do a buzz test and contribution test on the injectors to see if they could be the issue. Some more info on exactly what it is (or isnt) doing would help.

If it idles OK, but absolutely won't get out of its own way, then you might check that the EBPV didnt get stuck closed.

[76S&S]

The CPS has already been replaced, it absolutely died when it went bad.

It cranks (starts) but has a horrible miss. I had an injector go bad about three years ago and the symptoms were similar. Missing is worse this time though.

[jschildm]

No CEL, I assume?

[76S&S]

Correct, no CEL.

[TayMC197]

Originally Posted by jschildm

If its glow plugs it will start hard, but once it is started, run just fine. If it starts and still runs like chit for an extended period of time, then there is something else wrong. Cam Position Sensor is a weak spot on them. If you have someone with a scan gauge or auto enginuity, then you could do a buzz test and contribution test on the injectors to see if they could be the issue. Some more info on exactly what it is (or isnt) doing would help.

If it idles OK, but absolutely won't get out of its own way, then you might check that the EBPV didnt get stuck closed.

Yes a cold glow plug will do that, then the cylinder is flooded and takes it a little bit to start firing properly. A failed glow plug won't ever ignite, which cuases the same symptom to be perminate.

Yes, run a tech 2 or similar device on it if you have it or know someone with it. If not time to visit a service shop. They can check your balance rates on your injectors and make sure they are all firing properly. Normally if an injector fails you'll have more symptoms than just missing. It will white smoke (even at idle), have fuel in your oil, knock like crazy... Might not be all of these but at least 1. Normally injector issues, it will still run and move around okay, just smoke and knock like crazy.

Those 2 things are going to be your most likely cuases... beyond that you are looking at possible turbo issues (i believe the 7.3 is a wastegate setup), valve issues (such as breather valves, bypass valves), Position sensors like jschilm said, ecm/wiring issues.

Sadly I blew my turbo on my 08 LMM Duramax yesterday... I'll spend the weekend rebuilding it... ohh fun Thanksgiving for me. lol