Misfire could be a number of things:
a) spark plugs - change them if used over 15K miles - inspect/regap.
b) spark plug wires - change them if over 15K miles - inspect
c) ECM (electronic control module) - test with HEI (high energy ignition) tester.
The shaking tells me that the engine is running on less than its normal compliment of cylinders - the shaking is produced by the imbalance caused in the engine by one (or more) cylinder(s)
not firing at all.
The "Check Engine" light probably is coming on due the the misfire condition. Go to Pep Boys or
Advance Auto Pats, where they'll tell you (free) your codes causing the "Check Engine' light to be
lit - the code coming from your truck's computer will probably be one or more of:
P0300 - Random/Multiple Cylinder misfire detected
P0301 - Cylinder 1 misfire detected
P0302 - Cylinder 2 misfire detected
P0303 - Cylinder 3 misfire detected
P0304 - Cylinder 4 misfire detected
P0305 - Cylinder 5 misfire detected
P0306 - Cylinder 6 misfire detected
P0307 - Cylinder 7 misfire detected
P0308 - Cylinder 8 misfire detected
P0313 - Misfire detected with low fuel
SOURCE: vehicle shaking like it is missing real bad
when was the last tune up done and fuel filter was changed?
there is no spark plug wires I had to replace the boot for the number one cylinder on a 2000 expedition that was also having the same problem if the check engine light is on take it to auto zone and they will put it on a tester free of charge and I hope and pray that it is not the problem like the one I am working on right now I am replacing the upper and lower intake gaskets
SOURCE: service engine soon light comes on and engine in
The blinking light indicates a sevier miss fire. Get the codes scaned to determine which cylinders and we can go from there.
Auto Zone will scan codes free of charge.
Chances are you have an ignition coil or injector driver issue.
let me know.
Regards,
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