engine misfires

[djyelloboy]

my engine keeps mis firing but the check engine light is not on and i checked the cylinder coils and that was not the problem either. i took it to the shop and they couldnt find what was causing it. has anybody on here had this problem also? if so what causes it?

[Blackened300a]

my engine keeps mis firing but the check engine light is not on and i checked the cylinder coils and that was not the problem either. i took it to the shop and they couldnt find what was causing it. has anybody on here had this problem also? if so what causes it?

Hopefully you don't have the dreaded burnt valve from lack of cooling in the head. Is it popping out the exhaust on the driver side?

[SpartaPerformance]

Did you check your spark plugs? One may have backed out.

[justbob]

We really need more to go on here, MPH, idle, how many miles, what was done recently???

[tjl006]

Do a compression test, then go from there. I like you started with evrything but the compression test $200 dollars in parts later I needed the heads rebuilt.

[djyelloboy]

it does it mostly when goin up a hill or pulling a load. its most common at around from anywhere between 30 and 60 mph. nothing was done recently to it and it only has 56,000 miles. i didnt check the spark plugs and i dont know about the burnt valve.

[LeoVampire]

First things first. When the engine is stone cold after sitting over night check each of the spark plugs make sure they are in proper if all is okay there pull them out one @ a time and take a look to see if any of them look differnt from the others it might help with indicating which cyl is miss firing. Check the gap and so forth.

If you have an ohms meter preferably digital to get a more acurate reading check the coils put the pos lead on the left hand prong of the wire conector and run the neg lead to the bottom of the spring. Mark down the results of each coil check and see if you have a problem there.

If you can rent a set up to do a compression check while your @ it just to make sure there is no problem internaly and log the results.

If you find nothing on all 3 counts then you need to do a load test @ a shop where each cylender can be checked to see which of the coils are cutting out on you under pressure.

Doing the first bit of the process on your own if your capable will save you some bucks instead of paying a shop to do it all.

Once you have more info to present someone might be able to help you further.

[lastdaze04]

If you can rent a set up to do a compression check while your @ it just to make sure there is no problem internaly and log the results.[/QUOTE]


AUTOZONE may let you use one for free if you stay on the property and don't leave. That is where I found that cylinders 7 and 8 had low (125 and 65lbs) compression. They are fixed now:D FWIW
Rick

[burt ragio]

Dude don't get so discouraged just find a good shop or Mercury dealer not some wrench head with greasy pants that calls himself a mechanic. If you can't do the work of previous posts mentioned. I'am sure it is a simple fix.

[justbob]

I'm a wrench head with greasy pants? LOL To get the most accurate readings doing a compression test, it should be done with the throttle body wide open. Autozone rents these for free and yes you can take it home. I crank from 5-7 seconds per cylinder till the guage goes up and levels off, record each cylinder onto paper. I remove all plugs and throw the COPS all to the side and remove the fuel pump fuse. This way you can check all eight in a matter of minutes. Whole job = 20 minutes start to finish. And I do mine on a slightly warm engine............flame suit on.

[Blk Mamba]

sounds like coils, or the connector springs.

[burt ragio]

I'm a wrench head with greasy pants? LOL To get the most accurate readings doing a compression test, it should be done with the throttle body wide open. Autozone rents these for free and yes you can take it home. I crank from 5-7 seconds per cylinder till the guage goes up and levels off, record each cylinder onto paper. I remove all plugs and throw the COPS all to the side and remove the fuel pump fuse. This way you can check all eight in a matter of minutes. Whole job = 20 minutes start to finish. And I do mine on a slightly warm engine............flame suit on.

Didn't mean for you to take it the wrong way it's an expression. As you can see I did say to try the above post mentioned that are suggested by knowledgable people. I should have clarified it further "knowledgable wrench heads" No disrespect ment.

[justbob]

I was pulling your leg friend, I knew what you meant. I have VERY dry humour sometimes.:beer:

[djyelloboy]

ill probably just end up taking it to the shop cuz i really dont havew the know how to or time being in college and playing football! but thanks for all the input i really need to learn more about my car!

[Marauderjack]

sounds like coils, or the connector springs.

^^ BINGO!!!:cool:

[Trinicrew]

I have the same issue with mine but i will check all plugs next. I already checked all coils.

[Trinicrew]

I have the same issue with mine but i will check all plugs next. I already checked all coils. Even replaced one that was ticking loud. It still does it after replacement of coil but not as bad as before.