1998 Shutters upon acceleration (1 Viewer)

[Nefyn]

So it only used to happen when accelerating above 55mph, and no shuttering when cruising, just hitting the gas. Now it’s happening at any speeds and a little when sitting at a stop light. Today the check engine light started flashing for about 10 seconds then stopped. Any ideas????

 

[MountaineerLC]

First step is get a code reader and see what codes you have. If the check engine light was flashing then stopped you may have a misfire that comes and goes from a bad coil or plug.

I'm not 100% sure on Toyotas, but when the check engine light flashed on my old Rover it meant a misfire.

 

[JunkCrzr89]

Flashing CEL = Misfire is so bad that You may be causing damage to the cats (dumping fuel).

 

[Nefyn]

Flashing CEL = Misfire is so bad that You may be causing damage to the cats (dumping fuel).

Thanks guys. What could be causing the misfiring?

 

[Ayune]

Bad coilpack(s).

 

[Peter S]

A bad coil caused these same symptoms on my 100. The bad coil caused a misfire that initially felt like a shudder/vibration, it quickly got very bad and the truck was almost un-drivable. I limped it home, scanned it, replaced the coil on cylinder 6, and it has been fine since.
I now keep a spare coil (and tools) in my winch bag so I don’t get stranded far from home, I guess these coils going bad is kinda common.

 

[BullElk]

Sometimes you will not get a CEL on nor will it have a code to read....but still have symptoms of a misfire for some reason. If reading your scan guage it may still have a pending code available to check. Usually that will continue into an actual code with CEL on. Even as a pending code it can tell you which cylinder to check. Then you may want to swap the coil pack at that cylinder and check results. Also check that spark plug. It could be a bad or broken plug at the cylinder as well.

I had this misfire issue recently with no CEL light and no code. Only a pending code. Found that the plug was cracked on firing end. New plug solved that issue.