1999 Engine jumping

[Rockt]

1999 Toy 4Runner. usually between 50-60 MPG the engine will jump or stutter. Happens at low speeds also. It cause the vehicle to shake a bit when it happens. Tranny shifts beautifully. Not sure what it is - help? All coil packs, spark plugs and wires have been replaced.

tim

 

[CJ3Flyr]

between 50-60 MPG the engine will jump or stutter...
tim

Don't touch it!:lmao::lol:


I don't know a lot about that specific engine but in general I'd check the crank position sensor (it may use a cam position sensor). The other thing that I may consider would be O2 sensors. That vintage T4R has issues occasionally and if the O2 sensor is causing it run very lean that would cause 50-60mpg and a stumble/skip. Clean the MAF too on principle. They all need a MAF cleaning periodically.
:cheers: