Missfire in 5.7 hemi
Asked by GuruW3XGP Jun 01, 2018 at 09:22 AM about the 2010 Dodge RAM 1500 SLT Crew Cab RWD
Question type: Maintenance & Repair
I have a 2012 Dodge truck with a 5.7 hemi
the code is 306 miss fire on 6 and multiple
missfire it has new plugs new coil on
number 6 all cylinders pass compression
test at 120 psi visual inspection of value
spring none are broke but still getting
missfire on 6 and multiple missfire
6 Answers
jetjurnigan answered 6 years ago
Run some injector cleaner thru your next tank o' gas. The gas mite also be problematic. Short of that, do you have an engine scanner capable of reading live data? It's the best money you'll ever spend on your electro/mechanical mechanical marvel
Thanks I put a bottle of cleaner in last night I don't have a live scanner could it be the camshaft sensor ? Thanks again
jetjurnigan answered 6 years ago
Just because you don't have a check engine lite doesn't mean you don't have a problem anymore than the CEL being lit means...you do. Your problem can range from anything like something as simple as a dirty air filter to a vacuum leak, weak fuel pump, bad fuel injectors, bad O2 sensors to a clogged catalytic converter. Then, if you've got a bad cat the next thing you'll need to know is what caused it. BTW, all these problems can occur without setting off a check engine light. So as you can see, guessin' can get real expensive, real quick. I know that the urge and suggestions from folks who had a similar problem to shoot the parts cannon at your pickup is prolly overwhelming, but unless you have a really fat wallet n lotsa time...troubleshoot first. Get the scanner first, then get live data on both upstream n downstream O2 sensor/s, long n short term fuel trims, coolant temp n intake air temp readings vs outside air temp n last but certainly not least, find out if you have any current or pending codes. Do your checks at idle, 1500 n 2500 RPM, only once the engine is at normal operating temp at steady load conditions. You can all this in your driveway. Write them down n get back. Unless your problem goes away, o' course.
I got it fixed thanks for the response it was a process first I had bad plugs causing a miss the miss lead to a back fire that bent an intake push rod I replaced the push rod and got the compression back to 120 also put new coil on number 6 and it ran but still would get a miss so I replaced the cam sensor and it ran better but not just like before so I did another compression test all cylinders pass so I checked all injectors with an ohm meter they all passed so then I replaced the crank sensor and the ol girl runs like a scalded dog no problems thanks
Crankshaft position sensor and camshaft position sensor will display random misfire codes.
Christopher answered 4 years ago
a wipped cam lobe will do this too. if it comes back do a cam and lifter swap. since you know it for sure had a bent push rod you should probably change the cam and lifters anyway. these engines are just like the old ones when it comes to the cams. they like to eat them.