2019 5.7 very rough idling and other oddities

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southerncross

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2019
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Hello and thanks for your thoughts/advice in advance.

My 2019 Ram 5.7 started to develop a occasional misfire about 2 years ago. It would come and go so I never worried much about it. Ram electrical systems in my opinion... lets just say they do not age well. Maybe we spend too much time near the gulf coast and salt water. The misfire (P304) started to get worse and seemed to really get bad as the weather warmed up and humidity started to rise. I also noticed various little electrical anomalies. Such as overhead lights pulsing at idle. I replaced the TIPM and the battery. Things seemed to get better. Then they didn't and the occasional misfire came back and slowly got worse. It would occasionally go away sometimes for a month or 2 and would run much better in cold weather. Today the check engine light started flashing and a chime would sound when it flashed. I got a P304 and a P306 code. As well as P0174, P2098, B1208 and codes related to the rear drivers side light assembly being unplugged due to being filled with rainwater somehow. The wiring connector is corroded badly so I left it unplugged. Hoping its not a lifter and/or MDS issue. The electrical issues just make me feel like there might be an electrical issue causing everything.

Thoughts?
 

tron67j

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Assume you are original owner as problems have been going on for 2 years. This is important because with your corrosion you have noted my first thought is flood vehicle.

I have never encountered a Ram electrical system "not aging well" and with your stated corrosion the first place I would start is checking all major connection points and cleaning/repairing any that are suspect like ground connections, fuses being clean and seated properly, etc.

You have a lot of codes that signal misfires, possible air leaks, etc. before chasing those down with replacing things like injectors, sensors, etc. get your wiring in order per above; my two cents is you have wire/connection problems. If you aren't the original owner look up under the dashboard and look at metal areas as a lot of rust there can be indicative of a vehicle that was flooded.
 

BenchTest

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@tron67j solid info here. I have the pulsing map lights/interior lights thing going on in my RAM as well. It annoys me when I kick the map light on at night and it's pulse pulse pulse. I have put a meter on my electrical to see if I can see any voltage ups/downs but haven't been able to pinpoint anything. If that's the only electrical issue that presents, I'll live with it.
 

Sherman Bird

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Assume you are original owner as problems have been going on for 2 years. This is important because with your corrosion you have noted my first thought is flood vehicle.

I have never encountered a Ram electrical system "not aging well" and with your stated corrosion the first place I would start is checking all major connection points and cleaning/repairing any that are suspect like ground connections, fuses being clean and seated properly, etc.

You have a lot of codes that signal misfires, possible air leaks, etc. before chasing those down with replacing things like injectors, sensors, etc. get your wiring in order per above; my two cents is you have wire/connection problems. If you aren't the original owner look up under the dashboard and look at metal areas as a lot of rust there can be indicative of a vehicle that was flooded.
@tron67j solid info here. I have the pulsing map lights/interior lights thing going on in my RAM as well. It annoys me when I kick the map light on at night and it's pulse pulse pulse. I have put a meter on my electrical to see if I can see any voltage ups/downs but haven't been able to pinpoint anything. If that's the only electrical issue that presents, I'll live with it.
Is the pulsing with or without the engine running? Your meter is a very poor diagnostic tool for that type of problem due to it's signal being buffered AND the result of averaging peaks and valleys.

An oscilloscope would be necessary to pin point line interference. Also, I'd eliminate excessive AC ripple on the system. That can be done effectively with a DVOM.

A voltage drop test is called for, both positive and negative. My wife's Sorento did that "winking" when the car was running (as she put it), and I discovered a high ground resistance between the battery and the engine. I ran a shunt ground and it has been fixed for about 4 years now.
 
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southerncross

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I am the original owner and it has never been flooded. We do spend a good bit of time down by the coast but not on the beach per say. Pulsing of the overhead lights is with the engine running at idle. Doesn't pulse with the engine off, only when running and I believe only at idle. I will check tonight as it is hard to tell during the day. I have checked for vacuum leaks and the PCV seems to be good. It rattles. All plugs, wires and ignition modules were replaced about 20,000 miles ago with oem parts.
 

Dean2

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Have you checked that your intake manifold bolts are at the right torque. If they are loose, it will cause rough idle as well as sporadic misfires. Also, open the engine fuse box and make sure every fuse is seated by pushing down gently on each one. My bet is many will click into place. That has also been known to cause issues.

Once these easy checks are done then go to the more complicated stuff.
 
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southerncross

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I have not but I certainly can. Seems like I read somewhere yesterday about that. Ill check shortly.
 

Dean2

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I have not but I certainly can. Seems like I read somewhere yesterday about that. Ill check shortly.
Loose fuses are VERY common, I check mine every 12 months. Intake manifold torque is only 14 INCH pounds, so don't overdo tightening but often you find you can easily turn them with a 5/8" or 8MM nut driver and that is far too loose. Wild One is the fellow that put most of us onto the loose intake bolts.
 

Zoe Saldana

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Hello and thanks for your thoughts/advice in advance.

My 2019 Ram 5.7 started to develop a occasional misfire about 2 years ago. It would come and go so I never worried much about it. Ram electrical systems in my opinion... lets just say they do not age well. Maybe we spend too much time near the gulf coast and salt water. The misfire (P304) started to get worse and seemed to really get bad as the weather warmed up and humidity started to rise. I also noticed various little electrical anomalies. Such as overhead lights pulsing at idle. I replaced the TIPM and the battery. Things seemed to get better. Then they didn't and the occasional misfire came back and slowly got worse. It would occasionally go away sometimes for a month or 2 and would run much better in cold weather. Today the check engine light started flashing and a chime would sound when it flashed. I got a P304 and a P306 code. As well as P0174, P2098, B1208 and codes related to the rear drivers side light assembly being unplugged due to being filled with rainwater somehow. The wiring connector is corroded badly so I left it unplugged. Hoping its not a lifter and/or MDS issue. The electrical issues just make me feel like there might be an electrical issue causing everything.

Thoughts?

Try some Redline S! Fuel System cleaner.
 
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southerncross

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I don't have a torque wrench that small but I did check them and all were easy to turn with a 1/4" driver and 5/16 socket so I tightened them until they gave a little resistance and stopped. Doesn't seem to make a noticeable difference at idle but I will take it on a road test and see how it behaves under a little load.

On a fuel system cleaner note. When I started using fuel system cleaner around 80,000 miles is when the check engine light started coming on more frequently. Every time I would add some it would come on within 20 miles of driving.
 
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Sherman Bird

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I don't have a torque wrench that small but I did check them and all were easy to turn with a 1/4" driver and 5/16 socket so I tightened them until they gave a little resistance and stopped. Doesn't seem to make a noticeable difference at idle but I will take it on a road test and see how it behaves under a little load.

On a fuel system cleaner note. When I started using fuel system cleaner around 80,000 miles is when the check engine light started coming on more frequently. Every time I would add some it would come on within 20 miles of driving.
Which fuel system cleaner did you use?
 

BenchTest

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Is the pulsing with or without the engine running? Your meter is a very poor diagnostic tool for that type of problem due to it's signal being buffered AND the result of averaging peaks and valleys.

An oscilloscope would be necessary to pin point line interference. Also, I'd eliminate excessive AC ripple on the system. That can be done effectively with a DVOM.

A voltage drop test is called for, both positive and negative. My wife's Sorento did that "winking" when the car was running (as she put it), and I discovered a high ground resistance between the battery and the engine. I ran a shunt ground and it has been fixed for about 4 years now.
I agree, the multimeter isn't the best option. It was the "what I have at my disposal currently" option. The pulsing was/is at idle. I haven't put time into it to see if it exists above idle or engine off. It's just annoying on the very few times I use those lights. I don't notice anything else happening electrically that makes we want to investigate it any further. I've spent enough hours working on this truck so I'm going to let sleeping dogs lie with this one.
 

Atcer2018

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Hello and thanks for your thoughts/advice in advance.

My 2019 Ram 5.7 started to develop a occasional misfire about 2 years ago. It would come and go so I never worried much about it. Ram electrical systems in my opinion... lets just say they do not age well. Maybe we spend too much time near the gulf coast and salt water. The misfire (P304) started to get worse and seemed to really get bad as the weather warmed up and humidity started to rise. I also noticed various little electrical anomalies. Such as overhead lights pulsing at idle. I replaced the TIPM and the battery. Things seemed to get better. Then they didn't and the occasional misfire came back and slowly got worse. It would occasionally go away sometimes for a month or 2 and would run much better in cold weather. Today the check engine light started flashing and a chime would sound when it flashed. I got a P304 and a P306 code. As well as P0174, P2098, B1208 and codes related to the rear drivers side light assembly being unplugged due to being filled with rainwater somehow. The wiring connector is corroded badly so I left it unplugged. Hoping its not a lifter and/or MDS issue. The electrical issues just make me feel like there might be an electrical issue causing everything.

Thoughts?

The tail light sockets are replaceable. If it’s badly corroded you may want to replace it. I suggest going with OEM as some have had CEL issues using aftermarket.
 
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southerncross

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After driving it under a little load nothing seemed to change. I think it ran slightly better but who knows for sure. Same codes are back.

I don't remember the fuel additive that I used.

Would it be ridiculous to just replace the injectors and O2 sensors. Doesn't seem like it would be difficult in the least on this engine.
 

Zoe Saldana

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After driving it under a little load nothing seemed to change. I think it ran slightly better but who knows for sure. Same codes are back.

I don't remember the fuel additive that I used.

Would it be ridiculous to just replace the injectors and O2 sensors. Doesn't seem like it would be difficult in the least on this engine.

I'd start with the low cost things first and move up. Try Redline s1
 

Dean2

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After driving it under a little load nothing seemed to change. I think it ran slightly better but who knows for sure. Same codes are back.

I don't remember the fuel additive that I used.

Would it be ridiculous to just replace the injectors and O2 sensors. Doesn't seem like it would be difficult in the least on this engine.
If it is injectors or sensors you will get codes telling you that. No point in replacing stuff on a guess, the parts canon gets expensive. Track down the codes you are getting and work from there. Live monitoring of it running using an mx+, may also give you some leads. As will running a vacum gauge. Do not start replacing parts until you have figured out the issues.
 
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Sherman Bird

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After driving it under a little load nothing seemed to change. I think it ran slightly better but who knows for sure. Same codes are back.

I don't remember the fuel additive that I used.

Would it be ridiculous to just replace the injectors and O2 sensors. Doesn't seem like it would be difficult in the least on this engine.
... as ridiculous as sending a thousand dollars to some televangelist who promises you a miracle after you plant a "seed"... Yeah!
 
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