WTH shudder and shake

Drove home with a load of feed. Got back in truck after unloading and started up, rough idle spitting and sputtering. No CEL, so wait till morning and cold start same thing. Let it warm up a bit pulled out and CEL came on. Drove to work, bad shudder give it gas to get on down the road and CEL would start flashing. Get to work ck the code reader nothing (OBDII) push delete button head out to my work area, CEL is out but still feeling a miss. Rev it out between shifts CEL flashes but doesn't stay on. Get to my building and it is still running rough like a miss. So I guess what I'm saying or asking is does anybody have a idea of what's going on? Coil pack, bad gas, plug, plug wire, baffles me that there's no code and what does it mean when the CEL is flashing?

 

Have you searched for what it means if the CEL is flashing?

It's a severe misfire (more than 50% I believe) and it's warning you that unburnt fuel is making its way into the exhaust system, and potentially your cats.

If you don't have any codes yet, you at least know you have a misfire. Any one of those items you mentioned, coils, plugs, wires, could be a culprit. When was the last time you changed your plugs or wires? I'd also suggest checking out your grounds if it was as sudden as you say.

But, you really shouldn't drive it with the flashing light. Your cats won't last long.

 

there are count limits built into the PCM for each code. if the misfire count hasn’t reach its limit, the PCM wont turn on the CEL. There is a special category of “pending codes”, that is the PCM has recognized there is a problem but the threshold count hasn’t been reached so no CEL. See if your scanner can show you Pending Codes.

 

plugs and wires were done about this time last year. Was getting ready to send it to my fixit guy for trans drain and refill 212k, rack bushings and bushings in shifter. Just ran to the napa store for some sea foam for the tank, I try to run some through every couple of tank fillups. Cel flashed a couple of time then stayed on. It so when I get off work and head back by the shop I will check for codes again. I'm in a bad spot cause I have 30 miles to home. My cats are now almost 3 yr.s old aftermarket. really figured it was upper o2 sensor for whatever reason I'm going through 1 about every year.

 

If you're going through 1 O2 sensor a year, then there's something definitely wrong with your air/fuel mixture that is ruining the sensor.

 

So where do you start? I can replace it and everything runs great, good mileage, good performance. But this time so far I have no code to go by.

 

Take a look at your ground wires and ensure that you don't have some other electrical issue prior to throwing cash at sensors. There is one at the battery, one off the black of the block, and another near the diagnostic port on the intake manifold. Take them off, hit them with a wire brush, and some dielectric grease.

Next move on to the plugs and wires. It might be that you just need to reseat the coil packs/wires onto the plugs. Did you use OEM wires when you changed them out? I've seen aftermarket wires not seat well before, and cause a misfire.

 

they were auto zone wires. i'm thinking about replacing the coil packs anyway due to age it's a 02.

 

You need a scan tool that can display live data, and monitor pids related to combustion (fuel trims, injector pulse, maf, map, etc) so that you can see what's actually going on. If plugs, wires and coils were recently done, my first guess would be injectors.

 

Get yourself some OEM or Denso wires asap. The coil packs are pricy, especially OEM ($100 online pricing each). But again here, Denso or OEM only.

But first, try pulling everything, probably spark plugs included, and inspect it all... It really might be just a poorly seated cable/tube. Don't throw money at parts because of age unless they are prone to age-related failures.

OEM Parts:
Wires: 90919-15551, 90919-15552, 90919-15553
Coils:

$122 90919-02212 Toyota Genuine Parts - Coil, Ignition (90919-02212)

90919-02212 x3

Denso parts:

 

thanks for the parts info my mechanic is very meticulous about trouble shooting he will swap wires around and such to see if the problem moves, coil packs are original. Just plugs and wires were changed this time last year.

 

Look and make sure the valve cover isn’t leaking oil down into the plug hole, causing the misfire.