Rough Idle with AC On
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Rough Idle with AC On
I have read through a lot of this form looking for something similar. I found a bunch of threads on rough idle and misfires due to injectors but I have a little different situation...
I have a 2012 6.7L with 115K on it. I have so far replaced the fuel filters and ran a couple of tanks of fuel with some Powershot fuel cleaner. What is going on right now is with the Air Conditioner on the whole truck vibrates weather I am in park or in gear. It is almost like a shutter that does not change with engine speed. If I turn off the AC over a matter of a minute or so the vibration goes away and stays away. There are no CEL or codes ON the dash...
I am getting it scanned tomorrow by a friend just to check injectors but am skeptical that is what it is. Anyone else ever see this happen? Maybe the water draining from the condenser is shorting something out or the load from the AC compressor is just enough to cause the misfire due to injectors?
I have a 2012 6.7L with 115K on it. I have so far replaced the fuel filters and ran a couple of tanks of fuel with some Powershot fuel cleaner. What is going on right now is with the Air Conditioner on the whole truck vibrates weather I am in park or in gear. It is almost like a shutter that does not change with engine speed. If I turn off the AC over a matter of a minute or so the vibration goes away and stays away. There are no CEL or codes ON the dash...
I am getting it scanned tomorrow by a friend just to check injectors but am skeptical that is what it is. Anyone else ever see this happen? Maybe the water draining from the condenser is shorting something out or the load from the AC compressor is just enough to cause the misfire due to injectors?
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Have changed or checked your air filter too?
Also are you deleted? If not, might want to check out the EGR as well. Just thinking of things that a slight load could cause a rougher idle... You are also close to the service life of the DOC/DPF processing plant torpedo that is under the truck as well. Obviously some has lasted a very long time, but other's have failed earlier than the miles you have on as well. Your tech friend that is checking injectors could probably check how all that stuff is working out too.
Maybe M-CHAN or Ford_Doctor can chime in. Since they are Ford techs, they might have a better solution for you.
Also are you deleted? If not, might want to check out the EGR as well. Just thinking of things that a slight load could cause a rougher idle... You are also close to the service life of the DOC/DPF processing plant torpedo that is under the truck as well. Obviously some has lasted a very long time, but other's have failed earlier than the miles you have on as well. Your tech friend that is checking injectors could probably check how all that stuff is working out too.
Maybe M-CHAN or Ford_Doctor can chime in. Since they are Ford techs, they might have a better solution for you.
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This truck is 100% stock, no tuner or EGR / DPF delete. Although, once I get this cleaned up I am planning on it.
Man, you guys are really helpful. I will get under it tmmr and check the belts and tensioners.
OK, so have him scan and check the sensors in the DPF system also in the exhaust...good idea. If you have any other ideas that would be great.
I have rebuilt gas motors of all sorts but this is my first diesel...man what a different engine these 6.7's are
Man, you guys are really helpful. I will get under it tmmr and check the belts and tensioners.
OK, so have him scan and check the sensors in the DPF system also in the exhaust...good idea. If you have any other ideas that would be great.
I have rebuilt gas motors of all sorts but this is my first diesel...man what a different engine these 6.7's are
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My buddy plugged in the scanner last night. He could only communicate to some of the modules. He could see the BCM, brake system, heating / cooling and some others but not the PCM or the engine control module. He thought something may be pulling the comms line down to those. Going to head back out today and start unplugging some modules to see if we can isolate. Any other ideas in this ???
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Alright. I think we found the issue. Long story short one of the cooling fan blades was broken completely off. Not sure how the previous owner would have broken this but the other blades were a little roughed up on the tip closest to the motor. We watched on my buddies scanner that as the fan rpm went up the vibration got really noticeable. Wondering if I should do the fan clutch or just the plastic blades.
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