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Rozay_palm 07-16-2014 12:37 AM

check engine light problem
 
hey guys first time posting
so ill try and make it short.so i have an 06 GT. Mods=full exhaust with longtubes,underdrive pullys, ford racing cold air, 4.10 gears, and tune.
after i installed my long tubes i had a lot of problems with my CEL alot of slow response codes. bama eventually fixed the problem. i thought.
i also replaced the 02S.
about a week ago the light came on again, this time for multiple misfire codes and multiple cylinder misfires. i thought it would be good to replace the plugs and coils(50k on engine) i cleared the codes and after two drive cycles the light was back on with only three codes a multiple mis and a cylinder 3

could it be as simple as a bad plug or coil? tune?
appreciate some help. thank you.

Lethaldosage423 07-16-2014 02:00 AM

It could be all of that.
Does the car feel like is has a misfire?
If so, with the car running unplug coil number 3. Does the car run worse or the same?
If it runs worse you probably have another cylinder misfiring as well.

If the run doesn't change with the coil unplugged, plug it back in and unbolt the coil. With the engine running, pull the coil up a little. Can you hear it?(it will make a snapping noise)( be careful not to Get a shock, they suck.)

If it is snapping, the coil is working .next, ensure you put the correct spark plugs In.
If it is not snapping, most likely the coil is bad.

So let's say correct spark plugs and the coil works. Next you want to check the fuel injector. Easiest way is to use a mechanics stethoscope or a long screwdriver. Place it on the cylinder 3 injector (middle of the injector) is it clicking? Listen to the other injectors, do they sound the same? If yes then your injector is good. If no then you want to check for a signal so get yourself a noid light, it's a small light that plugs into the injector plug off your harnes. Plug In the noid light and start the car, is the light pulsing? If he's them you have signal so most likely tour injector is bad. If no then you may have a wiring harnes issue, broken wire or bad PCM .

So if you have spark and fuel,you may have low compression on that cylinder. Do a compression test .

If you still suspect the coil. Mark it, swap it with say cylindr 1 ,clear the CEL and drive it and see if you still get a cylinder 3 misfire or see if it's now a cylinder 1 misfire.


I kinda sped through the basics so it may be confusing. Feel free to ask any questions and I'll get back to you
-Chris

Lethaldosage423 07-16-2014 02:02 AM

After re reading your post, you could try flashing the car to stock then re uploading your tune just to see if that makes a difference

AMDanBailer 07-16-2014 10:12 AM

Quote:

Originally Posted by Rozay_palm (Post 8409160)
hey guys first time posting
so ill try and make it short.so i have an 06 GT. Mods=full exhaust with longtubes,underdrive pullys, ford racing cold air, 4.10 gears, and tune.
after i installed my long tubes i had a lot of problems with my CEL alot of slow response codes. bama eventually fixed the problem. i thought.
i also replaced the 02S.
about a week ago the light came on again, this time for multiple misfire codes and multiple cylinder misfires. i thought it would be good to replace the plugs and coils(50k on engine) i cleared the codes and after two drive cycles the light was back on with only three codes a multiple mis and a cylinder 3

could it be as simple as a bad plug or coil? tune?
appreciate some help. thank you.

This could be a number of different things. I would recommend returning the car back to stock and see if the codes follow. If so, then we rule out the tune and can continue to troubleshoot what's going on here. That is the quickest/cheapest way to start!

We can also look into your tune for you to see if we notice anything out of the ordinary. Just give the Bama team a call and they'll gladly look into this for you! Our Bama Performance tuning specialists are here in the building Monday-Friday from 9AM-5:30PM EST and Saturday 9AM-5:30PM EST. You can hit them up directly at 888.226.9764 and they'll get you squared away!

-Dan

Rozay_palm 07-16-2014 11:51 AM

i really appreciate the reply's.
Lethaldosage423. i never really felt a misfire, nor does it run bad right now. it has power and when i floor it, it doesn't seem to mis. but first i will mess with the tune and see what happens. also i will go over what you recommended. thank you!

Rozay_palm 07-17-2014 12:37 AM

ok so i switched cylinder 3 and 1 and deleted the codes...
code came back on...when i got home i re flashed my car to stock. ran ****ty.
and the CEL came back.
the codes were...
oxygen sensor heater circuit 1 bank sensor 2
and back 2 sensor 2
bank 1 too lean
bank 2 too lean...
and it read the oxygen sensor codes twice
i had a total of 6

Rozay_palm 07-17-2014 01:57 AM

also...do you think re tuning will at least make it run better?

808muscle 07-17-2014 02:24 AM

Sounds like some sort of air or vacuum leak. Check all around your cai, something is leaking there. Aftermarket coils suck. Stick with the stockers.

Lethaldosage423 07-17-2014 10:51 PM

did you run your car without the tune and it ran poor?

you should re upload your tune. if you have an intake and headers, it will only run properly with the tune.

so no more misfire codes?
like 808 said, sounds like a vacuum leak.
do you have a scanner that will read a live data? you could use that to check the ranges of your 02 sensors and compare them to bank 1 to see if any are out of range.

A lean code will quite often trigger an 02 sensor code.

also
i see you have a cold air intake.
is it an oiled filter?
is there too much oil on it.
a very common cause of system too leak bank 1 system too lean bank 2 is the mass air flow sensor. A lot of people over oil their air filters and the oil gets on to the tiny sensor element causing incorrect readings.

sorry for all the possible scenarios, its difficult to diagnose without the car.

With the engine running, do you hear any hissing sounds?
get yourself a can of carb or brake cleaner. with the engine running, spray a small amount round the intake manifold and vacuum lines. does the idle change at all? if yes then you have a vacuum leak. This is kinda a shady test. the proper way to check for a vacuum leak is with a smoke machine but they are pricey! Just be careful with the brake cleaner, its HIGHLY flammable.

Let me know what you find

Rozay_palm 07-18-2014 05:24 PM

well i didnt get to post this yesturday but, i did re-tune the car. after i tuned it i drove it for 20 plus miles and no codes yet..
so im thinkign it was just that, i will post again if something new happens.
so far so good!
thanks for all the help.


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