03 Cobra hesistates/ backfires under wot or above 4000 rpms

[rubior]

thers nothing behind the carpet either, so no bap right?

These. I had the same issues with ix plugs gapped @ .028. Switched to regular TR6's gaped like above, bam, issues gone.

should i try gapping the ix plugs first? or just get the tr6s & gapping them like you mentioned?

 

[03cobra#694]

should i try gapping the ix plugs first? or just get the tr6s & gapping them like you mentioned?

Not sure, I had the ix's for a while, but out of nowhere they got stupid. I'd try the .028 gap first. Not cheap plugs.

 

[rubior]

As stated above that appears to be a 2.93 or even a 2.8 pulley. My initial concern was fuel cut out. Mine did this when I first got it due to my twin GT40 fuel pumps connecting wire being loose. However as has been stated above gap those plugs to .28 and retry that. Regardless of fuel and such I’d do my best to make sure no moisture is getting into the cap. Buddy had that issue on his mach1. He went thru so many tanks drops just to find out his cap had a crack in it. Report back when you’ve gapped the plugs and such

Fuel filter is my guess,

Hard to change,,very tight spot

Has these symptoms

I also had this issue to say just filter can cause this,

Coils have been known to get weak and not give codes,
Ford racing sold a set of 8 which some of us have gotten .

Home

Terminator Cobra Home

www.terminator-cobra.com

Here you will find our service manual,,full PC version has this side of repair,
Very helpful

iv

 

[rubior]

i think i found my issue…
i replaced them with tr6s & gapped them @ .28 & im about to test drive it, im honestly shocked they melted… ive nver seen it happen, when i took off the plugs i sticked a magnet & just dust came out, ill update once i drive it

 

[slow98cobra]

Be VERY careful, you are leaned out and have pre-ignition. I wonder how much timing is in the car. I think you have a fuel problem and your tune needs checked. Your motor is at stake or is already pretty hurt especially with the missing pieces of those plugs. Don’t push it!

 

[Black02GT]

Be VERY careful, you are leaned out and have pre-detonation. I wonder how much timing is in the car. I think you have a fuel problem and your tune needs checked. Your motor is at stake or is already pretty hurt especially with the missing pieces of those plugs. Don’t push it!

+1, that pic is nightmare fuel.

 

[DSG2003Mach1]

i think i found my issue…
i replaced them with tr6s & gapped them @ .28 & im about to test drive it, im honestly shocked they melted… ive nver seen it happen, when i took off the plugs i sticked a magnet & just dust came out, ill update once i drive it

Replying so it tags you - as mentioned above to eat up plugs like that you have something big time wrong going on, hopefully it’s not already hurt

 

[rubior]

Replying so it tags you - as mentioned above to eat up plugs like that you have something big time wrong going on, hopefully it’s not already hurt

update: issue is fixed, i didnt really push the car, & i dont plan on pushing it but it runs so much better, & just merging on to the freeway it felt perfect, it feels like a totally different car now, i will definetly get it checked & retuned, i havent checked for the chip in the ecu but i thank everyone for their input & ill be checking on these plugs & hopefully this issue dosent occur again. the plugs that came with the car were motorcaft platinums, & they didnt melt off or nothing, theyre still in good shape & ill post a picture of them in a bit

 

[DSG2003Mach1]

update: issue is fixed, i didnt really push the car, & i dont plan on pushing it but it runs so much better, & just merging on to the freeway it felt perfect, it feels like a totally different car now, i will definetly get it checked & retuned, i havent checked for the chip in the ecu but i thank everyone for their input & ill be checking on these plugs & hopefully this issue dosent occur again. the plugs that came with the car were motorcaft platinums, & they didnt melt off or nothing, theyre still in good shape & ill post a picture of them in a bit

the problem is NOT fixed, it's just not misfiring/detonating YET. I would highly recommend NOT going wide open throttle, or even close to it until someone who knows what they're doing can look it over and give it a clean bill of health.

the melted plugs are a SYMPTOM of the issue - NOT the cause of it

 

[1FastFord]

I would definitely get it tuned and have a shop look it over