Misfire issues
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Misfire issues
I've got an 85 e-350 with a 300 straight six in it and its been giving me some issues. I bought it a couple weeks ago, its my first ford. It was misfiring occasionally when I bought it. Since then I have replaced the plugs and wires, distributor rotor and cap, ignition coil and ignition module. I have not checked the timing on it yet and the idle is a bit rough. The misfiring is particularly bad when I shift into forth gear, so bad that I cannot accelerate up the slightest incline. I'm getting 9-10 mpg as well. Thanks for any insight/pointers in advance.
Andre
Andre
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Joined: Apr 2011
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From: Orlando area
Check for vacuum leaks. Spray some carb cleaner around intake to head gasket and carb base. Any change in idle speed indicates a leak.
Also don't forget to check your fuel system (change the filter and check pressure/volume from the pump).
Good luck.
Also don't forget to check your fuel system (change the filter and check pressure/volume from the pump).
Good luck.
FTE Legend
Joined: Jul 2010
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From: Northeast, OK
And, there are always the myriad of vacuum hoses that, given their quarter-century age, are usually brittle and some times cracked. Ditto the plastic fittings, check valves, etc that Ford used. So check all your hoses and associated hardware.
I agree it probably isn't electric at this point. While an electrical issue can certainly cause the reluctance to accelerate, and especially when under high load such as in top gear, a very lean air/fuel mix can do the same.
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Thank you for the input! greatly appreciated.
I checked the gasket and it does seem to be leaking, the rpms increased increased when I sprayed the cleaner on it. I will pull and clean the carb tomorrow and replace the gaskets.
I can't find any leaks in the vacuum lines but I will look more tomorrow.
I will change the fuel filter tomorrow. What is the best way to check the fuel pump pressure/volume?
I checked the gasket and it does seem to be leaking, the rpms increased increased when I sprayed the cleaner on it. I will pull and clean the carb tomorrow and replace the gaskets.
I can't find any leaks in the vacuum lines but I will look more tomorrow.
I will change the fuel filter tomorrow. What is the best way to check the fuel pump pressure/volume?
FTE Legend
Joined: Jul 2010
Posts: 32,875
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From: Northeast, OK
I've not worried about the fuel pump pressure nor volume. In my limited experience if the pump works it usually has enough pressure and volume. But, most inexpensive vacuum gauges have a fuel pump scale on them if you really want to test it.
By the way, if the truck wasn't in daily use there is a good chance that the gas in the tank is bad and that there's junk or rust in the tank. Because of the problems I've had with junk in the tank of the old trucks I've bought I run two filters - one ahead of the pump and one after. And, I use the cheap see-thru plastic filters so I can tell when it is time to change, and I change them frequently early in the game.
By the way, if the truck wasn't in daily use there is a good chance that the gas in the tank is bad and that there's junk or rust in the tank. Because of the problems I've had with junk in the tank of the old trucks I've bought I run two filters - one ahead of the pump and one after. And, I use the cheap see-thru plastic filters so I can tell when it is time to change, and I change them frequently early in the game.
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