Cyl 3 misfire

[R_wilson2012]

Good day everyone.im having a head scratching issue with my '12 5.7 have a misfire that suddenly come on in #3 and only happens if I demand a little extra (ex.to pass a vehicle) and fuel mileage has gone through the roof.have been doing a process of elimination started with new plugs ngk g power platinum (as per some of the posts here,which have been very helpful i might add),then replaced the coil pack,than moved to what turned out was a faulty injector and now a new cam sensor.the motor runs excellent with no tick until the misfire than you can feel it struggle (but still no tick)I am steering away from cam because of how it runs,but I could be wrong.lol I'm new to the dodge and 5.7 hemi world and any help will be appreciated. I will be doing a compression test this weekend just as a precaution. Motor has 207000kms

 

[Fast69Mopar]

Good day everyone.im having a head scratching issue with my '12 5.7 have a misfire that suddenly come on in #3 and only happens if I demand a little extra (ex.to pass a vehicle) and fuel mileage has gone through the roof.have been doing a process of elimination started with new plugs ngk g power platinum (as per some of the posts here,which have been very helpful i might add),then replaced the coil pack,than moved to what turned out was a faulty injector and now a new cam sensor.the motor runs excellent with no tick until the misfire than you can feel it struggle (but still no tick)I am steering away from cam because of how it runs,but I could be wrong.lol I'm new to the dodge and 5.7 hemi world and any help will be appreciated. I will be doing a compression test this weekend just as a precaution. Motor has 207000kms

With how many 5.7 HEMI's have lifter problems I would stop driving this truck yesterday and start performing some diagnostics ASAP before you trash the short block by allowing all of the potential metal shavings to flow through the motor.

I am dead serious about this too. From what I could tell from your post it looks like you replaced the plugs, a coil and an injector and it still has a cylinder #3 misfire. Even without the HEMI Tick these motors still have lifter problems.

If it were me I would pull the intake manifold and inspect the VCT solenoid screen for metal. Then I would remove the left bank rocker cover and bar the engine over by hand and watch the #3 valves and their movement and compare them to cylinder #1.

 

[R_wilson2012]

Thank fast69mopar.i was trying to avoid pulling the intake and valve covers but looks like i have a weekend project.lol one question for you I found the faulty injector after I did the plugs do you think #3's plugs could have fouled?still going to pull the covers this weekend i have only had the truck a couple of months and hate to have to give up on it so quickly.paid less than a new motor is.lol

 

[Fast69Mopar]

Thank fast69mopar.i was trying to avoid pulling the intake and valve covers but looks like i have a weekend project.lol one question for you I found the faulty injector after I did the plugs do you think #3's plugs could have fouled?still going to pull the covers this weekend i have only had the truck a couple of months and hate to have to give up on it so quickly.paid less than a new motor is.lol

It is always possible to have fouled the spark plugs with a failed injector.

Question? How did you know the injector had failed? Did you have a constant cylinder #3 misfire that went away with the replacement of the #3 injector?

Did you use a noid light to verify that the injector was receiving its proper power and driver from the PCM or did you stick a long screwdriver against the body of the injector and you didn't hear any clicking from the injector?

Even if you pull the intake manifold and rocker covers off and you don't find any metal in the screen for the VCT it is cheap insurance to verify the mechanical integrity of the motor.

 

[Burla]

Those arent the correct plugs even though people have done well with them. Maybe not your issue, but swap coils packs and plugs with another cylinder see if it travels. Cams can fail without tick, it is a high possibly that 3 cam lob is toast, that is how they tend to fail. No other codes except 3 misfire?

 

[Burla]

2012 is a special year, only year with the 65rfe and if paired with 3.92's it is a very popular and desirable ram year. I would wager the issue started with previous owner.

 

[R_wilson2012]

It is always possible to have fouled the spark plugs with a failed injector.

Question? How did you know the injector had failed? Did you have a constant cylinder #3 misfire that went away with the replacement of the #3 injector?

Did you use a noid light to verify that the injector was receiving its proper power and driver from the PCM or did you stick a long screwdriver against the body of the injector and you didn't hear any clicking from the injector?

Even if you pull the intake manifold and rocker covers off and you don't find any metal in the screen for the VCT it is cheap insurance to verify the mechanical integrity of the motor.

I used the alphaobd graphs for the injectors and when I gave it throttle(not very much I may add) #3 cut right off to nothing and stayed like that for roughly 20 seconds retested when I put the new injector in and it stayed steady after some throttle.

 

[R_wilson2012]

2012 is a special year, only year with the 65rfe and if paired with 3.92's it is a very popular and desirable ram year. I would wager the issue started with previous owner.

Previous owner put a used motor with roughly 50000 and the ecm from that motor. At least they were told that mileage when I got into the ecm through alphaobd It told a different story of 207000kms.lol drove the truck for 4 months no issues at all purred like a kitten.they sold it cause their young lad bought his own truck and didn't need it.not sure of the gearing I had the diff cover off because it had a right rear wheel bearing gone but couldn't find any #'s on the gear set.i may have missed them too was doing it on my back and turning driveshaft at same time.lol I know it revs about 1600rpm at 100kms/h if that helps determine the gears.lol

 

[R_wilson2012]

Those arent the correct plugs even though people have done well with them. Maybe not your issue, but swap coils packs and plugs with another cylinder see if it travels. Cams can fail without tick, it is a high possibly that 3 cam lob is toast, that is how they tend to fail. No other codes except 3 misfire?

Have done the coil swap still 3 going to try the plug swap today and see.and yes it is only #3 no other codes and only happens if i give it a little throttle.if these are not the correct plugs what ones would you suggest?any suggestions are welcomed.

 

[Burla]

oem Mopar has 2 iridium and copper/nickel, so not iridium. These were the last ones I bought from Mopar store/.

 

[Wild one]

Have done the coil swap still 3 going to try the plug swap today and see.and yes it is only #3 no other codes and only happens if i give it a little throttle.if these are not the correct plugs what ones would you suggest?any suggestions are welcomed.

Do Not buy plugs off Amazon or Ebay,especially NGK's,buy them from Rock Auto or a local brick and mortar shop or the dealer.Your 12 will call for the older cheaper copper plugs.
The majority of NGK plugs on Amazon or Ebay are knock-offs and aren't actually legit NGK's.
A few minutes googling fake plugs will give you lots of information on fake plugs on both sites

 

[Burla]

Do Not buy plugs off Amazon or Ebay,especially NGK's,buy them from Rock Auto or a local brick and mortar shop or the dealer.Your 12 will call for the older cheaper copper plugs.
The majority of NGK plugs on Amazon or Ebay are knock-offs and aren't actually legit NGK's.
A few minutes googling fake plugs will give you lots of information on fake plugs on both sites

Rick, is there a way to tell if you got a knockoff?

 

[Dean2]

Do Not buy plugs off Amazon or Ebay,especially NGK's,buy them from Rock Auto or a local brick and mortar shop or the dealer.Your 12 will call for the older cheaper copper plugs.
The majority of NGK plugs on Amazon or Ebay are knock-offs and aren't actually legit NGK's.
A few minutes googling fake plugs will give you lots of information on fake plugs on both sites

Good info, was about to order some Denso FK20HBR11
Iridiums from Amazon for the Lexus. Will get them from Rock or the Dealer instead.

 

[Wild one]

Rick, is there a way to tell if you got a knockoff?

If you google fake NGK's,there should be several video's pop up on how to identify the fake ones Mike.
NGKs and Denso's apparently have the worst rep for being copy cat knock offs.
If the plugs are alot cheaper on Amazon or Ebay then anywhere else,good chance they're knock-offs.

Google Search

John even has a video up,and how he got took with fake NGK's

WATCH OUT FOR FAKE NGK SPARK PLUGS

In today's video we discuss fake ngk spark plugs and how we come across counterfeit spark plugs in the garage that we have used in our Dodge Dakota and other...

www.youtube.com

 

[R_wilson2012]

If you google fake NGK's,there should be several video's pop up on how to identify the fake ones Mike.
NGKs and Denso's apparently have the worst rep for being copy cat knock offs.
If the plugs are alot cheaper on Amazon or Ebay then anywhere else,good chance they're knock-offs.

Google Search

John even has a video up,and how he got took with fake NGK's

WATCH OUT FOR FAKE NGK SPARK PLUGS

In today's video we discuss fake ngk spark plugs and how we come across counterfeit spark plugs in the garage that we have used in our Dodge Dakota and other...

www.youtube.com

I'm with you on that wild one.i don't buy parts period offline.i go too my local parts store or canadain tire for tune up stuff.

 

[Wild one]

Good info, was about to order some Denso FK20HBR11
Iridiums from Amazon for the Lexus. Will get them from Rock or the Dealer instead.

Dean check your local Bumper to Bumper for Denso's. My local one used to keep a good stock of Denso 3381's on hand as they knew i'd be in every spring buying a set of them,lol

 

[Dean2]

Dean check your local Bumper to Bumper for Denso's. My local one used to keep a good stock of Denso 3381's on hand as they knew i'd be in every spring buying a set of them,lol

Thanks, checked Bumper to Bumper, Toyota dealer at $25 a plug, is 10 bucks a plug cheaper. Lexus dealer wants $42 per plug, Parts King is the same price as the Toyota dealer and they have them in stock. Rock Auto at $20 each, is cheaper than the Dealer or Parts King but only has 4 plugs and by the time you add shipping, $28.50, works out to about the same cost as the dealer. Can't wait till they start adding 25% tariff.

Checked direct from Denso, $23 each, free shipping on all orders over $69, and no GST.

Video make by Denso themselves on how to spot fakes.

DENSO Spark Plugs Genuine vs Fake

This video will show you how to spot the differences between counterfeit and genuine DENSO spark plugs.

youtu.be

 

[Burla]

If you google fake NGK's,there should be several video's pop up on how to identify the fake ones Mike.
NGKs and Denso's apparently have the worst rep for being copy cat knock offs.
If the plugs are alot cheaper on Amazon or Ebay then anywhere else,good chance they're knock-offs.

Google Search

John even has a video up,and how he got took with fake NGK's

WATCH OUT FOR FAKE NGK SPARK PLUGS

In today's video we discuss fake ngk spark plugs and how we come across counterfeit spark plugs in the garage that we have used in our Dodge Dakota and other...

www.youtube.com

I think resistance tells the absolute story, I have 16 Mopar to go in soon, now I can test them. thanks

 

[Tominator223]

I used stock plugs in my gen3 & my coils lasted 350k + miles. I did the stock plugs always ,because I heard the coils were failing with other than stock plugs.

 

[aepowell]

When my cam failed I didn't get any codes at all. The truck ran great. It just had the tapping in the engine. My lifetime warranty paid for the replacement.