The Diesel Garage banner

2002 7.3 - Check engine light and rough running

19K views 30 replies 7 participants last post by  kainers 
#1 · (Edited)
Guys,
This weekend my check engine light came on and the truck started running rough when given any throttle. I took it to a local shop and the mech hooked up his computer and got a code(i think it was 1277) that indicated some electrical issue feeding the #7 cylinder. He replaced the wiring to the injectors on that side of the engine and it didn't help. When the truck is cold it runs fine and no engine light. After running 10-15 minutes, the light goes on and vibration starts. On the way home this afternoon the light actually went off and ran smooth for a few seconds then the light came back on and the shaking started again. Could this be an injector? Any suggestions would be greatly appreciated.

Tim

2002 F250 Crew 4x4 (everything is stock)
 
#5 ·
Guys,
Thanks for the input. I talked to the mechanic a few minutes ago and after more study, he suggested the possibility of a problem with the computer(I apologize for not knowing the proper acronym) in the truck which would require reprogramming at the least or a new computer all together. If so it will require a trip to the dealership. If the mech is correct, how much money should I expect to see to reprogram and how much to replace?

Tim
 
#11 ·
did the mechanic run a Buzz test on the injectors?Did he run a CCT.

The pcm controls basically the whole truck.It tells the IDM to fire what Injector for what cyl for what time.There is a bunch other factors but that is semi basics.A buzz test will tell the IDM to fire all 8 injs at the same time the start firing one at a time in order 1-8.Weak buzz you will hear cause the injector will be noticeably audible difference then the rest.

If the PCM need programming or replacement you would have allot more codes then just 1 for #7 cyl.IDM could be at fault but not entirely.A buzz test will tell allot.

To bad you didn't live in Southern Oregon I ain't doing NOTHING for the moment.
 
#13 ·
Tone won't always tell you a great deal, but it is helpful to know #7 sounds different.

If the Cylinder Contribution Test (CCT) could be run, it would tell you if that injector is problematic.

It could be your IDM still. Hard to diagnose over the internet.

I'd lean toward that injector first.

How many miles on the truck?

prt
 
#14 ·
At this point my IDE guess would be Injector #7.They will probably put the hook to you at 250 bucks or more for the injector and 200 for labor maybe less but 2hrs none the less.

If you know another 7.3 owner you could swap IDM's with them.All 99 and ups are located under the drivers wheel well.It is a pain getting that plastic off.I REALLY don't think it is an IDM.

If you could live without the truck and continue to look for updates on this thread for the rest of the day.Maybe someone else might have a better idea as to what the problem is.
 
#15 ·
I think it sounds like an injector... Pull that injector and one next to it it and swap them. If the problem changes to other cylinder then it is def. the injector. You can start the truck w/out putting it all back together also.
 
#16 ·
You guys are awesome for taking the time to help with this. The truck has 164,000 miles. I like the injector swap idea. I'll get with the mechanic and see what he thinks about it.

Another question, would an injector from a 1999 7.3 F250 work in my truck? He's got a wrecked 1999 at his shop. Just an idea?
 
#19 ·
Depends if the donor is an early '99 (AB injectors) or late '99 (AD's)--you can run a single AB in a pinch and if you don't have ANY other option, but it's probably better to track down an AD if you can. I bought a single AD from Swamps to R/R with my LL AE stick in #8 cylinder and it only cost me $150 so that's not a bad deal at all, IMO...
 
#23 ·
Should be--I stuck a reman AD in #8 and once I pulled the glow plug and spun the engine over a bunch of times to clear the cylinder, it ran (and still runs) like a champ.
 
#27 ·
Alright guys, we replaced the injector with a new one from Swamps and drove the truck. Everything seemed fine until it warmed up and the light blew up again and the vibration started again.:bang
We ran a the contribution and buzz tests again and the same results. Code 1277 high/low open(or something like that)

Any thoughts on where to start looking? ICM?

Tim
 
#28 ·
Okay,
We replaced the IDM and we still have the same light and code. Here is what's been done to so far:
1. Replaces the wire harness and cover gasket
2. Replaced the oil sensor(don't know the exact name)
3. Replaced the injector on #7
4. Replaced the IDM

Again, we are still getting a 1277 - high low open on cylinder #7. Any input on where to look next will be appreciated.


Tim
 
#29 · (Edited)
I just checked my PCED manual (2002 MY specific) and for probable cause of a P1277 it said "Open Circuit, Open Injector, Failed IDM" Are you positive you put a good/working IDM in when you R/R'ed your old one?
 
#30 ·
jvencius-Thanks for your research!
As it turns out, I called Dave at Swamps shortly after I made the previous post and he said to check the connection on the injector. He said that there have been numerous times that the connection to the injector had pulled loose when reinstalling the cover/gasket and that is exactly what had happened in this case. He said that everyone in his shop had done it at least once!

YOU GUYS CAN'T IMAGINE HOW THANKFUL I AM FOR THE HELP I'VE RECEIVED ON THIS FORUM! ALSO, DAVE & THE SWAMP DUDES ARE AWESOME. HE KNOWS FORD DIESELS AND HAS BEEN MORE THAN WILLING TO SHARE HIS KNOWLEDGE!

THANKS AGAIN TO ALL

TIM
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top