Engine Missing

[DORUN]

This is a 1999 S-10, Four Cylinder. It only cuts out at high speed. It idles fine and does fine a low speeds. The spark plugs, wires, fuel filter and air filter have all been changed. A good injector cleaner has been put in the fuel tank. A hand held diagonistic device was inserted but there are no 'error' codes. The 'Check Engine' light is not comming on. It is not backfiring.

 

What would cause the truck to cutout at high speeds?

[firecadet613]

What speed does it cut out at, the governor hits at 98mph.

 

Joe

[DORUN]

I don't know if it will go 98 mph! It starts about 45mph and gets worse approaching 70mph.

[CMNTMXR81]

Possible injector?

 

Just to thoroughly eliminate the spark side at least from a user side (not a Tech's), what kinda plugs, wires and what gap did you set?

 

These new D.I.S. and high energy systems are particularly finicky.  Using a plug that may cause a slight bit more resistance, will tend to fry the wires.  Running a plug with a gap too wide would also cause the same results.  As the flame kernel on the elctrode is either getting blown out or the gap is too much for the ignition to push (causing it to short out elsewhere like thorugh the wires).

 

I'd really stick to the fuel side though, seeing as though it seems to only happen at high rpm's would lend me to believe it's a fuel delivery problem.

[bowtie_pasta]

Since you mentioned basic tune-up parts, how about the distributor cap and rotor?  Did you check/replace these as well?