Help Chase the Misfire 99' SR5

[sixgun86]

When I first bought the vehicle it had a misfire on cylinders 3&5 with slightly rough idle. Smooth power under load. Looking at the plugs from 3&5 the gap was off. Almost touching the electrode. I replaced the wires and plugs, ran some injector cleaner. CEL turned off. Fixed the idle.

Week ago I was playing with the ECT while making a pass and the CEL came on again. This time it flashed. Threw of P0171 lean code. I proceeded to clean the MAF. Code went away.

Today, CEL came back on. Misfire cylinder 5 again. It has a smooth Idle. Smooth power under load. Wondering what to do now.....?

New wires
New NGK Plugs
Injector Cleaner
MAF cleaned (properly)
Switched coil packs around
Clean Oil, No loss of any fluid.

 

[004Gunner]

Have you listened to the injectors yet? A cheap stethoscope should allow you to hear whether or not the injector is functioning properly. You can also find a lot of info by searching "P0305"

 

[yotaah]

I ran into some of the same problems (misfire code primarily) and had the injectors pulled and rebuilt and that fixed it.

 

[whodini]

Sounds real similar to what's happening to me

Sixgun we seem to be having the same problem. Can you hold your rpms at a specific speed?

The suggestions you got from gunner and yota seemed to fix their problems. I'm going to give it a try. It's driving me nuts.