Was driving home from work ripping on it a bit trying to monitor the AF and tweaking the SAFC and everything felt ok. Got to my house checked the oil and made sure everything looked ok.

Left my house to my friends house and wasn't beating on it, got off the highway and was driving normal low speed and all of a sudden I got a strange slower rhythmic vibration like it wasn't running right. Feels like I'm misfiring. When I listened to the motor u hear a sort of ticking sound right under the manifold near the rear cylinders (5+6?). The car has been running really rich sometimes so maybe the plugs are fouled? Theres no check engine light. Car idles rough and dies out after a few mins. It's drivable just doesn't have power. My gauge clusters speedo doesn't work and some of the lights are out so who knows if my check engine light even works.

So what should i do now? What are my first steps to diagnose this? Jump the diagnostic port? See if the CEL even works? I've never done it before so I don't know what pins to jump or the procedure? Should i pull the intake manifold and check the plugs? Do a compression test? Any help would be great! Thanks everyone.

 

If you suspect a miss, or can hear it ( usually I listen to the exhaust) I would check the plugs.

Pulling codes is simple its just a jumper in the front (search) I forgot it since im obd2 right now.

Also I would double check whatever you were doing tuning wise before.

 

Still misfiring on Cyl 2 and 3. Checked the gauge cluster and appears that the CEL bulb was removed. Replaced it and got code 25 Air-Fuel Ratio Lean and code 27 Sub Oxygen Sensor signal. Proceeded to pull the Manifold and checked the plugs on Cyl 2 and 3. They looked kinda fouled but not really bad. The plugs are Iridium and only have 1000 miles on them. I cleaned all the plugs and wires but the wires had been submerged in oil from the bad valve cover leak. I put everything back together and still misfiring. Suspecting the plug wires at this point so im gonna pull the manifold again and test the wires using a test light inline with the plug. I was thinking the excessive amount of oil submerging the wires for an extended period of time could of damaged them. I am getting spark at the distributor because the spark is arcing when I pull the wires off to test for the misfire. Here are some pics and videos. Thanks for any help!

TESTING FOR MISFIRE THIS ONE DID CHANGE A LITTLE BIT SO I THINK THIS ONE ISNT MISFIRING AS BAD AS THE OTHER:



THIS ONE IS DEFINITELY MISFIRING THERE IS NO CHANGE WHEN I DISCONNECTED THE WIRE:



BARELY ANY LIGHTS GO ON WITH THE KEY ON ENGINE OFF





CYLINDER 2 PLUG



CYLINDER 3 PLUG

 

I was going to say the distributor and maybe plug wires if the plugs are fine

 

how does your rotor look inside the distributor, those do go out eventually and start dropping cylinders.
plug 2 looks wet.

 

It seemed like there was a strong arc of electricity from the distributor when I pulled the wires from the cap but maybe not strong enough? And I will be testing the wires tomorrow as well as a compression test.

I didn't check the Rotor inside the distributor. What would I be looking for? Just carbon tracks or something? I haven't dealt too much with distributors but wouldn't if the rotor was going bad it would misfire on all cylinders most likely?

Also the plug is probably a bit wet from the residue from that MASSIVE valve cover leak. I tried to clean the plugs as best I could.

Thanks for the help guys!!

 

there is a rotor in the middle that spins around (you must have seen it when swapping to the 4runner cap), and it has a flint looking stone on the end, this hits the points in the cap as it spins around, and when it contacts it will spark. over time, the rotor edge gets ground down, and it will start not making contact randomly, as a slight miss here or there, then give it a few more weeks, and in the middle of driving you will start to loose cylinders probably a few at a time until it no longer makes contact with any of the points in the rotor. when mine went I only lost 2 cylinders before I changed it, it is definately not an all or nothing type of thing.

Also since you are using a 4 runner cap, that is not helping things and I would definitely use a new rotor when changing caps, unless the one on there is relatively new. IF you have no idea, just change it is not expensive.

just clean the wires, generally they are the most reliable part of the whole system. mine worked after bending them various ways as you have to do with the 4 runner cap mod, stretching them, dropping things on them, you name it, they never stopped working for me.

I never did like the 4 runner cap but it did help just barely clear the turbo intake pipe (still leaned against it). Consider going coilpacks in the future.