3FE Engine misfiring @ high RPM (1 Viewer)

[Coolfishluke]

I have 92 FJ80, and on last long highway drive I had an intermittent problem with the engine 'missing' in firing, at around 65MPH and 2300rpm.

If I backed off on accelerate and went slower after a short while it cleared.

Initially I thought a fuel supply issue at the higher RPM so changed filter and prob still there.

I searched and found an article on similar problem in 4Runner that indicated and earth wire fault? Is this possible for 80?

Has anyone had similar problem and found a clear solution?

FYI Engine is 40K out for full rebuild and all components on top condition

Thanks for help

 

[jonheld]

I have 92 FJ80, and on last long highway drive I had an intermittent problem with the engine 'missing' in firing, at around 65MPH and 2300rpm.

If I backed off on accelerate and went slower after a short while it cleared.

Initially I thought a fuel supply issue at the higher RPM so changed filter and prob still there.

I searched and found an article on similar problem in 4Runner that indicated and earth wire fault? Is this possible for 80?

Has anyone had similar problem and found a clear solution?

FYI Engine is 40K out for full rebuild and all components on top condition

Thanks for help

This sounds like fuel delivery to me.
Is this repeatable in all conditions or does it only occur after a hour or more of driving?

There are 2 fuel filters. The inline filter is mounted to the inside right frame rail below the distributor. There is a fuel pump pre-filter or strainer or fuel sock (it goes by different names on the forum), but Toyota calls it a fuel pump suction filter. These should be replaced every 100K miles or so.