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HELP!!!!! misfire problems 98 expo 5.4

Old 11-28-2010, 10:59 PM
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Default HELP!!!!! misfire problems 98 expo 5.4

I am having severe misfire issues. It started about 2 weeks ago. I had number 3 spit a plug. Since I'm working out of town in Minnesota. I have no garage or proper tools with me so I took it to a shop that services fleets of fords. The repaired the plug and replaced the cop then replaced the other plugs with autolite double plats at a tune of 650. After that a day or so later it would misfire sporadically like a cop was starting to go out. I keep spares with me at all times lol. So here is where my problem started. I decided to Suprise my parents for thanksgiving and drove down to Kansas on the way the misfire became worse about 300 miles down the road and final through a code and it was p0308 misfire number 8 cyl. So I replaced the cop with a spare and then another and another still misfired so when I got to their house I replaced all cop With new motocrafts at 50 a piece ( it pays when ur brothers girl works for the dealership) and pulled and cleaned all the injectors then it still misfired Num 8 so I did what I should have done to start with and replaced the plug. It ran like a dream once I reset the comp. Drove 450 miles back up here today without a prob ran 80-85 the whole way up I35 and got 15 mph which is the best ever for that truck before I would get 13-14 running 70. When I arrived back to the hotel I parked it and went in for a couple hours. Then ran to the store for milk and it misfired like it did before I changed the plug. Wtf could be wrong. It hasn't thrown a code yet for me to check if its Num 8 again or another one. And its cold as azz out with a steady 40 mph wind any ideas. It's driving me nuts and costing me lots. If I wanted to drop this kind of cash I would buy a whole in the water (boat).
Old 11-29-2010, 09:28 AM
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Well here's an update
Drove the truck to doc today and on the way it ran like a champ till it got close to operating temp and the got worse now has a dead miss and has thrown a code and will check when I get out of the docs. My local mechanic said that I could be an intake basket leak since it has an aluminum intake there is little chance of it being cracked but a basket would make a lot of sense. He said that the head baskets generally don't go bad. He sees many of the fleet trucks get 600k before they are sold or overhauled. Wonder if one of those cold snaps we head the other day would cause that basket to go.
Old 11-29-2010, 09:33 AM
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Sorry for the horrible spelling etc.... this is supposed to be a smart phone lol. EVO 4g.....
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