misfire in cylinder 4...goes away when car is restarted...then comes back in 10min...

[qtxdevilz]

well i just got the timing done on my car satuday...then we took the car out and romped on it (it was snowing and we basically climbed mountains with it...)...then cylinder 4 just stopped working (either fuel or spark related)...but after we turn the car off and turn it back on again it would work fine for any where between 5-30 minutes...then it would do it again...i tried swapping plugs but with no success (which shouldnt be the problem anyway because when i restart the car it runs normal again...)...im thinking coil pack but does that take a shit on you and stop working forever or does it start to work again after i restart?any help is appreciated...thanks...

 

[braap]

How did the plug look when you took it out? wet? that could tell you if it was indeed spark related. You've checked the plugs so the only other variable left (aside from the coil itself) is the plug wire. A faulty wire could exhibit intermittent behavior...of course a faulty injector could also fuel foul your plug, but that would usually happen over a longer period of time...

 

[The Foos]

it has to be electrical...

check the ecu, the transistor pack, and related sensors...

Scott

 

[qtxdevilz]

it has to be electrical...

check the ecu, the transistor pack, and related sensors...

Scott

how do i check ecu?i got the codes pulled and it says misfire on cylinder 4...how can i check the coil pack?would the coil pack get ####ed up...then start working after i restart the car?

 

[98spyderboost]

Most FI cars have a diagnostic time for warm up where it uses default settings and assumes everything is ok for most of it's systems including A/F, timing, spark, etc...
I would experiment a little if you havent already. I would see if it is actually an exact timeframe(ie. 10 mins) or if it's just when it warms up. If it's at operating temp BEFORE you restart and it goes away for a specific amount of time then it can be a number of ECU or electrical problems. However if it runs good cold and 10 minutes later when it's at operating temp it starts to do it I would first check the plug, wire, then coil, etc. Also What does the plug look like? Is it wet, fouled, orange or brown, exceptionally worn tip, out of gap?

I had a somewhat similar issue with missfires after warmup on my old Dak, and it turned out that the plug was broken in two. For some reason the 8 min diag sequence on start up kept it going fine. But as soon as 8 minutes hit I lost a cylinder.

That's a pretty complicated problem to troubleshoot but keep at it. There are only so many parts you can replace before it gets fixed

 

[The Foos]

to check the ecu, you have to physically take it out of the car and take the metal case of it apart...there are 3 or 4 capacitors (cylinder shaped, in the center of the board) that tend to leak over time...this destroys the board traces and the other components around them...if this happens, it can make itermittent problems happen...

all you can really check on the coil pack is resistance (unless you can hipot them, most people don't have the equipment)

Scott

 

[qtxdevilz]

to check the ecu, you have to physically take it out of the car and take the metal case of it apart...there are 3 or 4 capacitors (cylinder shaped, in the center of the board) that tend to leak over time...this destroys the board traces and the other components around them...if this happens, it can make itermittent problems happen...

all you can really check on the coil pack is resistance (unless you can hipot them, most people don't have the equipment)

Scott

ive never heard of a 2g ecu having leaking caps yet...also you mean check resistance as in using a volt meter?what is it suppose to read?thanks...

 

[myblack98gst]

you didn't give any information as to what vehicle this is in or anything, but what is happening sounds alot like the issues with doing a 6 bolt swap into a 2g. That is exactly what mine would do. You may try doing the POT mod and see if that works.


10k potentiometer wired in series with the barometric pressure input to the ECU.. it keeps the ECU from looking for missfire. in probably 4 months mine has not done it a single time. where-as it used to do it every day.

 

[96whitetalon]

Also if you do have a 6 bolt you could just unplug your TP senser. Thats what i did to cure misfire

 

[qtxdevilz]

yes this is a 6 bolt in 2g...but the 6 bolt has been in the car for over 3 months already without this problem...the problem you are talking about is the random misfire problem...mine is not random misfire...my problem is cylinder 4 is not working at all unless i restart the car...

 

[myblack98gst]

okay do not belive me.... but I have been there, mine ran just fine for over 4 months then started to do it more with the cooler air coming in.


do the pot mod, I guarentee it will quit..

Mine was not a random missfire code either.. it just started a complete missfire, but have fun trying to find a faulty coil pack or plug wire for that one.

 

[qtxdevilz]

okay do not belive me.... but I have been there, mine ran just fine for over 4 months then started to do it more with the cooler air coming in.


do the pot mod, I guarentee it will quit..

Mine was not a random missfire code either.. it just started a complete missfire, but have fun trying to find a faulty coil pack or plug wire for that one.

do you have an aim or something?i want to talk to you...thanks...

 

[The Foos]

okay do not belive me.... but I have been there, mine ran just fine for over 4 months then started to do it more with the cooler air coming in.


do the pot mod, I guarentee it will quit..

Mine was not a random missfire code either.. it just started a complete missfire, but have fun trying to find a faulty coil pack or plug wire for that one.

Sorry...didn't know you had a 2g...I didn't think that you wanted to use a 2g computer with a 6 bolt...but I could be wrong...I know my 1g's front and back, but I haven't had to deal with a 2g, so I don't know all the quirks with them...

Anyhow, it sounds like a ecu issue or a mas sensor issue to me. If the problem gets worse as it gets colder, you aren't measuring the right amount of incoming air...I would think a vacuum leak, but since it resets after restart and it is only one cylinder, that kind of rules that out. I would check the mas when it is running right and then when it is running bad...see what changes...

As far as checking the coil, you have to check resistance of the coils...check both the primaries and secondaries...a haynes manual will tell you how to do this...it is not a voltage measurement. DON'T CHECK THE VOLTAGE on the secondaries. You will get 40k+ volts and at minimum smoke the fuse in your meter. Could destroy it.

good luck

Scott

 

[myblack98gst]

do you have an aim or something?i want to talk to you...thanks...

aim = donnienall626

 

[EcLiPsE-BoY]

aim = donnienall626

Ever try consulting a Mitsubishi Dealership they know these cars inside and out and have had lots of time to come into mostly all problems the eclipse/talon have most diagnostic cheks will solve the problems and give you a error code it might be costly but will give u Piece of mind to know how to solve this issue...

 

[coltboostin]

Ever try consulting a Mitsubishi Dealership they know these cars inside and out and have had lots of time to come into mostly all problems the eclipse/talon have most diagnostic cheks with sole the problems and give you a error code it might be costly but will give u Piece of mind to know how to solve this issue...

Holy crap that’s a good one.
If you asked them a question like this, especially about a 6 bolt in a 2g, they would look at you like you were an alien.

qtxdevils: How the hell are people suppose to help you when you have NO info about what kind of car you have available anywhere in your post? Your lucky Myblackgst knows what he is talking about. He is too nice, I would have just yelled at you and told you to research.

Do the POT mod, that is 100% your problem.

While your at it, solder one into your brain circuitry, it also may run better.

 

[EcLiPsE-BoY]

sheesh man i guess you are mr know it all so your saying the people who build these dam automobiles dont know sh%t coulda fooled me man i guess you're the one who needs a soldering joint welded to your brain they know every inch of these cars you don't think the own eclipses either nat why would they do that...

 

[coltboostin]

sheesh man i guess you are mr know it all so your saying the people who build these dam automobiles dont know sh%t coulda fooled me man i guess you're the one who needs a soldering joint welded to your brain they know every inch of these cars you don't think the own eclipses either nat why would they do that...

Spoken English lately?

 

[qtxdevilz]

you didn't give any information as to what vehicle this is in or anything, but what is happening sounds alot like the issues with doing a 6 bolt swap into a 2g. That is exactly what mine would do. You may try doing the POT mod and see if that works.


10k potentiometer wired in series with the barometric pressure input to the ECU.. it keeps the ECU from looking for missfire. in probably 4 months mine has not done it a single time. where-as it used to do it every day.

can anyone else confirm this?or had this happen to them before?thanks...

 

[CheapTalon]

This happens to many 6bolt swapped 2g's. One of the cases that I heard of also started roughly 3 months after also and he tried almost everything to fix it. Most people buy DSMlink cause it has a feature that cures Random Cyl #4 misfire too.

 

[qtxdevilz]

This happens to many 6bolt swapped 2g's. One of the cases that I heard of also started roughly 3 months after also and he tried almost everything to fix it. Most people buy DSMlink cause it has a feature that cures Random Cyl #4 misfire too.

just to make sure this is the problem where cylinder 4 stops firing altogether not just misfire...

 

[The Foos]

sheesh man i guess you are mr know it all so your saying the people who build these dam automobiles dont know sh%t coulda fooled me man i guess you're the one who needs a soldering joint welded to your brain they know every inch of these cars you don't think the own eclipses either nat why would they do that...

Hey...just FYI...car companies are in the business of making money, NOT designing/making a good car...I would never take my car to a dealership anyhow...chances are that you will pay twice as much and get it done half right...I will take my chances with myself and my Chevy buddies on figuring stuff out...

Scott

 

[coltboostin]

Hey...just FYI...car companies are in the business of making money, NOT designing/making a good car...I would never take my car to a dealership anyhow...chances are that you will pay twice as much and get it done half right...I will take my chances with myself and my Chevy buddies on figuring stuff out...

Scott

He will learn, probably the hard way soem day.

 

[EcLiPsE-BoY]

Well guys if I had the health to fix it myself I would but...unfortunaly I don't so I guess this makes me a loser for not being a grease monkey like you !

 

[kevingst]

Man, to own these cars, you gotta either be really able to work on it...or have LOTS of money so you can pay someone else to do it!