AG

Hey out there, I'm new to YotaTech but I've been searching for a while to find some answers to my multiple cylinder misfires on my 96 4Runner. First the CEL would come on but after a day or two would clear itself. I hooked up a code reader and saw that at different times it showed a different cylinder each time even after I cleared the history. A few days/week later the CEL would come on again. At first the performance change wasn't very much but then it started to idle rough from start up and doesn't really get much better on the road. In my searching I have heard everything from coil packs, spark plugs & wires, fuel injectors, fuel pumps, to other more complicated ideas involving loose bolts etc. If this is so common why is it this hard to find a solution??? I Love my 4Runner but can't drive it.....PLEASE HELP, THANKS!!!!

toyota4x4907

Start with the basics. Like you said- spark plugs, wires, cap and rotor, coil packs, ignition modules, etc,etc,etc.
Take a mechanics stethescope and listen to the injectors to make sure they are firing.

Is this a 2rz-fe, 3rz-fe, or 5vz-fe?
I might be beneficial if you post the exact code(s)

zlathim

I have seen this happen when the valves were in desperate need of adjustment.

Godzilla

Post your codes
Also, by chance have you had a timing belt changed in the recent past?

AG

Thanks for your responses, I dont have the codes so I cant post them until another Diag test is done, I haven't changed the timing belt but I think the mechanic who owned it before me did. And thnaks for the valve adj tip...anymore suggestions......

mt_goat

http://www.motor.com/MAGAZINE/Articles/012007_04.html

https://www.yotatech.com/forums/f2/c...ighway-128206/

Godzilla

Get the codes and list them if you want better help.

Do a process of elimination.
-Check plugs/wires (might as wel change them)
-If the codes are jumping then most likely not a coil pack.
-Check and clean your MAF (Do you run an aftermarket air filter?)
-Check crank pulley, cam/crank sensors, timing belt

AG

I was also told when it failed CA Smog Test that it was running rich....seems like the Yotas frustrate alot of owners with these issues!!!

sinister_rn61

I had a random cylinder misfire CEL and it turns out my head gasket blew.

kingbiscuit

That could just be the O2 sensor. I changed mine and it passed smog with flying colors afterwards. Before it was failing.

Definitely start with the spark plugs/wires. Don't get any fancy plugs just get the OEM suggested plugs. Pepboys suggested the wrong plugs for my vehicle and they overheated and melted my spark plug wires!! ers! Not to mention they cost more than the suggested ones. Just start with the simple fixes and move on from there.