I need some ideas?!?

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BLOWN00GT

New Member
Aug 16, 2006
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#1
i posted a thread a few weeks ago about my #3 and #5 cylinders both not firing. does anyone have any clue what it could be. i have a vortech blower, MAC longtubes and the complimentary full exhaust with a forged bottom end. never been tuned besides sending the ECU to vortech. its a 2000 GT and i recently tore it apart to do valve stem seals. i have done all the work myself(bottom, exhaust and blower). i am not sure if they were missing before the valve seal job or not. the car doesnt idle rough like it would if you would unplug one of the sparking plugs. but you can hear something missing in the exhaust. any ideas greatly appreciated, just throw as many out as you can and I will eliminate them one by one.

thanks guys!
 
#5
i have switched around coil packs and it remains the #3 and #5 cylinders not firing. i have swapped old plugs and new plugs around. still the same cylinders. and there is fuel on the plugs as i change them. so i believe the fuel injectors are firing, also they are new injectors and only have about 10,000 miles on them. they came with the supercharger kit!

so i believe that rules them out.
the fluid on the plugs is not oil nor coolant. I havent had to add any anti-freeze and the oil leak stopped with the new valve seals.
 
#6
i will see if the plug to the coil pack is getting power. if not than i have a wiring problem(burnt wire, fuse, ECU may be fried or something)

any of this sound like a possibility...

its not like i have forgotten to hook anything up. i have had this car and my brothers car apart several times. i know every plug and ground on the car. which also means i have already double checked all this. although it doesnt mean that a wire plug is busted or a wire burnt. but where would i look for this???
 
#7
but than again this is also happening in 2 places. one is on the back of the passenger side and the other is on the front of the driver side(aka #3 and #5 cylinders)

any ideas what would be making both these miss???

there are many plausible explanations for just one but for both to be missing? its a little tougher. that is why i am on here hoping someone has a good answer that i havent tried yet!

let me know and thanks again
 
#8
I don't understand how you've come to the conclusion that those 2 specific cylinders are mis-firing. perhaps some more backround info would help bring out some possible answers.:shrug:

our computer throws a code for a cyl mis-fire, have you gotten those codes? you said that its not as bad as if you pull a cop off while its running, so thats why I don't understand how you came to your conclusion. without getting the code that would be the way to tell.

get a tuner. then see where your at. with the amount of work you seem to have done I find it surprising you haven't spent the $400 for a sniper kit at least.
 
#9
i have one of the small computer readers from sears. it told me #3 and #5 are missing. and when un-plugged the motor makes no different sounds. for instance on a typical V8 if you unplug one coil pack it will idle really rough. this does not idle rough with both these cop's missing. yes it is wierd. i don't understand either. but the only way you can tell is because of the uneven flow of exhaust. but when i unplug one working plug, then the car starts to shimmy and shake when idling. which is what it is supposed to do. apparently when the right two plugs are missing on each side it smooths out the idle. try to unplug your #3 and #5 plugs at the same time... let me know what happens. i am sure it will look and sound different than all 8. but i haven't had all 8 firing properly in 4 months. but i do know what it sounds like with one missing... and it is certainly smoother with 2 missing than it is with 1 missing! I have no idea why and i am not full of ****... lol

i havent spent the $400 for a personal tuner because i have never heard if they were worth it. would it be something that would actually help me tune the car myself to where i would not need to take it and get it tuned. cause i would rather let someone who knows what they are doing tune it.

let me know guys.. thanks
 
#11
no i did not pull the heads. i did pull the timing chain off. some may say timing but i set the timing the first time when i rebuilt the bottom end. its extremely easy and everything lines itself up. also a suggestion of a blown head gasket. but i had no problems before the valve seals. so i would doubt that would be a problem. and i have pulled the plugs out and put in different plugs and nothing happened. it was still missing in those same cylinders. they are new plugs and have no miles on them as i have not moved the car since i installed them... just plain autolite plugs is what i have had good luck with in the past, so i use them. gapped around 30 thousanths.
 
#12
BLOWN00GT said:
no i did not pull the heads. i did pull the timing chain off. some may say timing but i set the timing the first time when i rebuilt the bottom end. its extremely easy and everything lines itself up. also a suggestion of a blown head gasket. but i had no problems before the valve seals. so i would doubt that would be a problem. and i have pulled the plugs out and put in different plugs and nothing happened. it was still missing in those same cylinders. they are new plugs and have no miles on them as i have not moved the car since i installed them... just plain autolite plugs is what i have had good luck with in the past, so i use them. gapped around 30 thousanths.
Click to expand...

pull it down , Id bet you are missing some pieces off the top of your pistons ...
 
#13
alright...
the plugs are sparking! and the cylinders have compression! and the plugs have unburnt fuel on them...
any advice greatly appreciated... thanks
and its not missing pieces off the pistons... that conclusion came from left field!
 
#14
just suck it up and take it to the ford place and see what they say, or another local mechanic that you trust. sometimes its best to get another head looking at it with more diagnostic tools when you have driven your self crazy for so long.
 
#15
i like that response! haha... even though i dont want to i just may have too. i have a buddy of mine who went to school to be a mechanic and gave me some advice when i was building the engine. he is on his way to my place today and we will see what he says. i have a feeling that he won't have any ideas for me...

will the ford dealership actually look at it with as many mods as there are too it? figuring that they won't work on it with the liability factor!
 
#16
i have some more info for everyone...

the scanner my buddy used was a little more fancy than mine and his read some more codes. his read the regular missfire code of P0303 and P0505. which is the missfire in #3 and #5...
his also scanned P0355 which is [Ignition coil E Primary Secondary CKT]
and a pending code which is P0356 which is [Ignition coil F Primary Secondary CKT]

i am assuming that the CKT mean circuit but not sure...

so i am wondering if anyone can shine some light into what these codes are. i figure that a large ford manual would better explain what is going on. so let me know what you guys can find out...

thanks too all!!!!
 
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