Another misfire grimlin
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Joined: Jan 2013
Posts: 98
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From: Germany
Another misfire grimlin
Ok so here is my ordeal and a lot of background. I've owned the truck for 2 years. 2005 fx4 5.4 3v. After about the first 6 months I did a complete tune up. All fluids and plugs as well as cop boots. No issues at all never had a single problem. At about the 1.5 year mark when I hit a hill on the highway it started misfiring and cel flashed but didn't stay on. The rest of the trip it ran fine (150 miles) then when almost home it did it again this time I has the sct hooked up and pulled #5. Cylinder misfire. Pulled the plugs when I got home and they looked fine so I put them back in. Ran good for about 3 months then started again (30-40 miles a day). This time the #5 cylinder electrode had burned off. So I changed the plugs and still had the problem. So I ordered new cops. No fix so I returned them and ordered another set. Still same issue. This is where sh** hit the fan. I installed...
Whipple 2.3 supercharger
Comp cams stage 1 blower cams
New valve springs
New timing kit with phaser lockouts
New rockers and lash adjusters
New plugs (FR zero degree)
New cops
New fpdm
Long tube headers
O/R y-pipe
And other things but not related to issue at hand
Before doing all this I did a compression and leak test. All cylinders were the same and none made has any noise out of intake,exhaust, oil cap and no bubbles in radiator. The misfire only occurs when under a load and it idles and drives fine otherwise. I have stayed out of the boost and only pretty much idled the truck back to my house when it happend since I'm also still breaking everything in. I have NO check engine lights on!
Any suggestions are helpful I have researched this a lot and everyone else's issues leads to cops or plugs but since this is my third set of each I'm lost. Also all the cops have good grounds.
Thanks
Will
Whipple 2.3 supercharger
Comp cams stage 1 blower cams
New valve springs
New timing kit with phaser lockouts
New rockers and lash adjusters
New plugs (FR zero degree)
New cops
New fpdm
Long tube headers
O/R y-pipe
And other things but not related to issue at hand
Before doing all this I did a compression and leak test. All cylinders were the same and none made has any noise out of intake,exhaust, oil cap and no bubbles in radiator. The misfire only occurs when under a load and it idles and drives fine otherwise. I have stayed out of the boost and only pretty much idled the truck back to my house when it happend since I'm also still breaking everything in. I have NO check engine lights on!
Any suggestions are helpful I have researched this a lot and everyone else's issues leads to cops or plugs but since this is my third set of each I'm lost. Also all the cops have good grounds.
Thanks
Will
