[KeMBro2012]

This morning, before I messed around with the o2 sensors on my 00, I polled the ECU for any codes. I had a pending code for "Misfire on random cylinders", which I cleared. It came right back. I tried this several times and it came back almost immediately each time. This is a recent occurrence, as I poll for codes every saturday and this is the fisrt time one has come up.

WTF?

So, I popped the hood and started looking around.

There are 8 brown wires bolted to the right side of the valve cover; these are the ground wires for the coil packs (one wire for each, split off into 2 wires each in the harness, grounded in 2 spots for redundancy). These wires fit individually into a brass ring that gets bolted to the valve cover for ground and these rings were both badly tarnished.

I pulled those rings and took a steel brush soaked in brake cleaner to the rings, the screws, and the mounting points, then wiped everything clean with a paper towel and put it back together and cleared codes one last time.

SHAZAM! Code stayed gone!

After I shut everything down, I went through and gave every single freakin' ground point I could find the same treatment and cleaned my battery contacts and clamps. I think I have a VERY happy Corolla right now.

I drove around for about an hour, freeway, city, granny driving part of the time, with intermittent (and prolonged) WOT and high (5-6k) RPMS. Still no code.

This seemingly severe problem was nothing more than a dirty ground. Always start with the simple stuff!

Oh, and even with a good 5min (not all at once!!!!!!) of 5-6k RPMs and WOT, I still haven't burned a drop of oil since doing what I described in my oil thread a while ago. I think it's at something like 1.5k miles and still RIGHT at the full line.

 

[silverone]

This morning, before I messed around with the o2 sensors on my 00, I polled the ECU for any codes. I had a pending code for "Misfire on random cylinders", which I cleared. It came right back. I tried this several times and it came back almost immediately each time. This is a recent occurrence, as I poll for codes every saturday and this is the fisrt time one has come up.

WTF?

So, I popped the hood and started looking around.

There are 8 brown wires bolted to the right side of the valve cover; these are the ground wires for the coil packs (one wire for each, split off into 2 wires each in the harness, grounded in 2 spots for redundancy). These wires fit individually into a brass ring that gets bolted to the valve cover for ground and these rings were both badly tarnished.

I pulled those rings and took a steel brush soaked in brake cleaner to the rings, the screws, and the mounting points, then wiped everything clean with a paper towel and put it back together and cleared codes one last time.

SHAZAM! Code stayed gone!

After I shut everything down, I went through and gave every single freakin' ground point I could find the same treatment and cleaned my battery contacts and clamps. I think I have a VERY happy Corolla right now.

I drove around for about an hour, freeway, city, granny driving part of the time, with intermittent (and prolonged) WOT and high (5-6k) RPMS. Still no code.

This seemingly severe problem was nothing more than a dirty ground. Always start with the simple stuff!

Oh, and even with a good 5min (not all at once!!!!!!) of 5-6k RPMs and WOT, I still haven't burned a drop of oil since doing what I described in my oil thread a while ago. I think it's at something like 1.5k miles and still RIGHT at the full line.

so did you do bennies engine oil consumptions fix, or something else?

 

[KeMBro2012]

I've been topping off with lighter weight synthetic oil (0w20 Royal Purple) as it's been burning. After roughly 300 miles of no burning, I added about a teaspoon of PTFE grease (Super Lube you can get at Harbor Freight) to a just-shut-off-after-a-spirited-drive engine, scrubbed all the deposits off the dipstick and coated that lightly in the same grease (basically to pass the time, no real purpose) to give the grease a bit of time to melt, then fired the engine back up, let it idle for a couple minutes, and took it back out for some more WOT/redline fun.

Not sure if the PTFE is doing any good, but I can tell you I used to be able to float gears somewhat fluidly before adding it (by the time I slipped it out of one gear and pushed it over to the next, the engine had slowed down enough that it would slide right into gear) and now it takes the engine a couple seconds to rev down enough that I can pop it into gear without using the clutch. I'd say things are a bit slipperier in there, now. This is a good thing, I think; except that I prefer floating during normal driving, it leaves the clutch in better condition for the abuse I give it during funtime.