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Feeling some misfiring at cruising speeds. First time around 55 and 60, only in higher gears, manual 6 gear. Car was sitting for a couple weeks. Doesn’t do it accelerating. Wondering if a fuel additive would help?
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Why not go to an auto parts store and have them use a scan tool to pull any codes that the car may have set? If there are codes stored, it might just tell you what is going on and then you can decide what to do.
Didn’t know auto parts stores offered this. Which one are you familiar with?
....all the large chains will scan your car for free (and clear codes if you like), just like free heating system checks in your home, it creates potentially buying customers when faults are found.....
....all the large chains will scan your car for free (and clear codes if you like), just like free heating system checks in your home, it creates potentially buying customers when faults are found.....
Some stores won't clear codes. Stores will also have a list of suggested fixes based on what they have sold to Customers before. Don't take their recommendation until you actually diagnose the problem since the vast majority of codes doesn't tell you what is wrong they just tell you where to start looking. Each code has a dianostic procedure that guides a person through an orderly process to determine where the fault is located.
Feeling some misfiring at cruising speeds. First time around 55 and 60, only in higher gears, manual 6 gear. Car was sitting for a couple weeks. Doesn’t do it accelerating. Wondering if a fuel additive would help?
A majority of misfire are ignition related…about 70%…if the car was sitting for much longer we can guess it may be a stuck injector…like Bill said don’t change parts based on the trouble codes…for instance you can have lean codes that make the engine misfire…you DON’T chase the misfire…you chase the lean code first…if the parts store can identify the misfiring cylinder or cylinders while you’re there it may help…misfires can be fuel, ignition, or mechanical…you just have to get into the right “funnel” and test that system including the electrical part…if you’re not doing the diagnosing take the car to a diagnostic shop…not a repair shop or a dealership…both are not good at diagnosing…where are you located ??
A majority of misfire are ignition related…about 70%…if the car was sitting for much longer we can guess it may be a stuck injector…like Bill said don’t change parts based on the trouble codes…for instance you can have lean codes that make the engine misfire…you DON’T chase the misfire…you chase the lean code first…if the parts store can identify the misfiring cylinder or cylinders while you’re there it may help…misfires can be fuel, ignition, or mechanical…you just have to get into the right “funnel” and test that system including the electrical part…if you’re not doing the diagnosing take the car to a diagnostic shop…not a repair shop or a dealership…both are not good at diagnosing…where are you located ??
Pull a plug on your own. I doubt your coils are bad. Ask them what tests they did to verify this? Did they just plug in a scanner or watch a real time log of the car actually running at speed?
If you do have a bad plug or wire they are correct to change them all.
Unless they look at secondary ignition using a scope they can’t verify that plugs and wires are bad…and I know they don’t use one…I’d tell them if they change the plugs and wires and it doesn’t fix it then you won’t pay for the repair…let them put your old plugs and wires back on and you move on to someone who can diagnose it correctly…dealerships don’t diagnose…they only replace parts !!..below is the secondary ignition waveform on my car…I can tell if the plugs, wires, or a coil is bad by interpreting this waveform.
Dealership says I need plugs and plug wires. What do you think am I being ripped off?
How many miles do you have on the car. Plugs arent due to be replaced till 100k miles. I have 112k miles still going but have new plugs to put in just get the time to have them put in
How many miles do you have on the car. Plugs arent due to be replaced till 100k miles. I have 112k miles still going but have new plugs to put in just get the time to have them put in
chances are they're well beyond their time-based change interval. head seizure is never fun - I'd do those sooner rather than later.
Feeling some misfiring at cruising speeds. First time around 55 and 60, only in higher gears, manual 6 gear. Car was sitting for a couple weeks. Doesn’t do it accelerating. Wondering if a fuel additive would help?
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Lights off in the dark open the hood and spray water on the wires. Bad wires will show exactly. Misfire codes identify by cylinder number. swap coils wires and plugs one at a time and see if the code follows the swap. If you have access to a bidirectional scanner a power balance test can help determine which cylinder is not contributing as much as the others.
Missfire
