BearsLexus

Yesterday on the <4 mile trek home from work, my 2000 AWD suddenly felt like it didn't want to accelerate. I pushed a little harder on the gas and it did, somewhat, and then the CEL started flashing.
Well, I laid off the gas pedal, since I know that's a really bad sign... and since I was only 1/2 mile from home on a 35 mph street, I figured I'd limp it home. Less than 1/4 mile later, the CEL stopped blinking, and just became solid lit. The car also suddenly felt like it was driving "properly" again. I tried to accelerate and it sped up as I am used to.

Anyhow, this morning, I started it up, let it warm up and checked my trans fluid which was properly full, and the engine oil is properly full (checked before starting). I drove the mile to the AutoZone and got my DTCs read. I got P0300, P0302, and P0306... Misfire codes...

Now any of you who are familiar with me and my Lexus, I have had plenty of problems with it... Rebuilt engine about 2 to 3 years ago, and a rebuilt Transmission and replaced front Differential less than a year ago... Mechanically this this SHOULD be sound. I don't trust it though. Probably never will.

Anyhow, the print out for those codes reads:
Defintion:
1. Large Vacuum Leak
2. Fuel System Concern.
3. Ignition System Concern.
4. Engine Mechanical Condition

Really specific, huh?

Has anyone else had a situation such as this, and if so, what can I do to ensure this situation doesn't happen again... especially with all the driving I may have to do tomorrow...? Basically, I need to know how to troubleshoot the problem quickly and effectively, so I can fix it and move on.

Baetke

P0300 is a multiple misfire code (set because of P0302 & P0306). When this code is set the engine computer will go into limp mode which is why you had poor throttle response.
P0302 is misfire on cylinder #2
P0306 is misfire on cylinder #6
Are you sure there wasn't a P0304 code as well?

Your misfires are all on Bank 2, the one closest to the radiator, so thank goodness for that.
If you had a P0304 too I'd suspect an OCV failure. If you really only had P0302,6 then try checking the coils for those plugs. This will be pretty difficult if you don't have your own code reader but you could swap a suspect coil, say #2 with a good coil, say #4 and see if the misfire moves to that cylinder. If it does, that coil is most likely bad.

BearsLexus

nope, didn't have a 0304. I don't have a code reader yet. Guess for the moment, I'll just have to keep my fingers crossed... get paid on Friday
Thanks Baetke.

OCV... oil control valve? that wouldn't be the VVT valves would it?

I'll let you know what I find when I find it!

Bear

Baetke

Yes, the OCV (oil control valve) controls the VVT. Failure of this valve is often associated with multiple misfires on one bank or the other. They each have their own OCV. Also associated with low vacuum as in, "my power brakes don't seem to work any more".
Please keep us posted on your progress. Solutions to these problems are the "gold" of this forum.

salimshah

Here is a reference:

http://en.wikipedia.org/wiki/VVT-i

VVT is a system while the OCV is one part of it. You are right, it stands for oil control valve.

Salim