Ok, so for a while now my truck has had a miss/studder at around 1200rpm. It's not everyday but it's there sometimes and it's annoying. I took it to rockin s and it passed buzz but #4 injector failed contribution. He replaced it and for about a day it seemed better, again it doesn't do it everyday. The next day it showed itself again, I would have called rocky but I'm a one chance kinda guy, if you don't fix it the first time I'm not goin back. So now I'm at a loss, it's a very sight miss at idle but it's pretty bad at 11-1300, but no where else does it do it in the rpm range. Already replaced the uvch, gpm, fuel filter and oil. Please help me figure this out!! 147k miles
7.3 miss at 1200rpm???????
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backwoodsboy
New member
What speed range?
Is it with the torque converter locked, or unlocked as well?
Is it with the torque converter locked, or unlocked as well?
Lethalthreat7.3
New member
Flat spot in the throttle position sensor. Can you consistently make it miss at the same rpm?
psduser1
Active member
Loose electrical connection, maybe at the uvch? I feel it comes and goes, I'd rule out mechanical.
No codes?
No codes?
lengelhardt
New member
I'd say look into the tps if you haven't already.
matthew.hussey.79
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To know for sure I would take it to someone who has a oscilloscope and scope throttle and injectors seen alot of wiring harness chaffing especially where engine harness on drivers side valve cover goes to bulk head connector will have to look on very bottom and on top of driver side shock mount area
Lethalthreat7.3
New member
My truck seemed to do the same thing, intermittant but seemed to happen usually after it had been running for awhile. No codes. Couldn't see it on AE but I could make it happen between about 1/16th and 1/8th throttle. Using an ohm meter I found a "flat spot", the resistance could be seen increasing, drop then pick right back up. Replaced and problem solved.
Curious to what you find. My obs does a similar deal. Once warmed up and driven for a while it will sputter a bit in the 1200 range when you lay into it hard on the higher chip settings. It is intermittent and comes and goes. I've been still trying to figure it out. In the factory tune position it will not do it at all.
I unplugged my tuner and it still does it. Mine does it on low speeds like from a stop and roll into slowly, plus it has a rough idle, if I floor it from a stop it goes through that range so quick it doesn't do it......I'm still looking for answers or suggestions
gnxtc2
Active member
My OBS does it also in the same rpm range, don't matter if it's idling or driving. I believe it's in the tune. Probably the only way to eliminate is by live tuning.
Billy T.
[email protected]
lincolnlocker
Well-known member
its a crap shoot if you dont have a way to monitor perameters and pull codes.
maybe pull driver side valve cover and make sure all the connections are tight. if it went away fir a while after replacing the #4 injector then maybe its a bad connection. possibly ohm out the wires from idm to injector.
live life full throttle
maybe pull driver side valve cover and make sure all the connections are tight. if it went away fir a while after replacing the #4 injector then maybe its a bad connection. possibly ohm out the wires from idm to injector.
live life full throttle
gnxtc2
Active member
Even with a scan tool, it would not give you the fuel/timing map vs EOT and other tuning info. I would like to overlay the datalog to the fuel/timing cells. In this instance, tuning software would beneficial.
Billy T.
[email protected]
Billy T.
[email protected]
