shark13

Hello,
I have a 99 RX300. This weekend the family and I did a little staycation. We drive over a 6600 ft. pass along the way. While making our way over the mountain, the check engine light came on. I continued to drive, still uphill, and noticed later the CEL light began to blink. We drove a bit further and pulled over to a safe spot. The light was blinking in intervals of 9. As we pulled into a parking spot I noticed the break booster did not seem to be working. I did the best research I could on my phone to understand what may have been going on. We stayed there for about an hour and made the decision we would continue on and that if the light began blinking again we would have it towed. Instead of the light blinking it stayed solid and stayed that way for the remaining forty minutes to our destination (which was mostly downhill).

Later that evening we were going to do a short drive (flat ground) and I noticed the CEL turned off shortly after leaving. This remained the case as we drove the 5 minutes to dinner and then back again. On the way back home from our trip I took a longer but less steep way. I was very easy on the car, going only about 45 mph, until I reached near the top of the hill. Unfortunately it was around this time that the light came back on and was stumbling off and on pretty bad. I had previously turned off the overdrive thinking this may be the culprit. I'm not sure if it had more to do with the fact the road leveled out, or that I re-engaged the overdrive, but the stumbling stopped. To be safe we stopped for about an hour along the way. The car was not driving perfectly (rough idle and slight lunge on acceleration), but the blinking light CEL did not occur again and stayed solid.

As soon as I made it home I ran the codes and received the following:
P0300
P0301
P0302
P0303
P1349

After some research it looks like the P1349 is a VVT Bank 1 (rear) malfunction. From what I have read so far it seems the most common cause for the P1349 error is a bad/dirty/both oil control valve. It also seems the P0300, P0301, P0302, and P0303 codes can be initiated by the P1349.

Are my above assumption fairly accurate? Should I consider starting with a new Bank 1 OCM? Are there perhaps more likely causes for this situation?

We had no issues with these codes on flat or downhill ground...only uphill. And, after some rest the code disappears. This is leading me to believe that much like a bad fuel filter, perhaps under load the filter in the OCM is becoming clogged to the point that it affect the driving and throws codes. If the vehicle is not being put under heavy load (going uphill) it can function enough in it's semi-clogged state to not cause any stumbling. Perhaps too that after some time the clogged filter settles. This might explain why the CEL turns off after sitting for a period of time.

Any thoughts?

Thanks,

P.S. After reading about the possible effects to the catalytic converter I kept an eye on it. I did not see it ever glow or turn red.

Marc

shark13

Hello,
I could really use some help. My last post got no replies.

I replaced the right (rear) variable valve solenoid thinking that would take care of pistons 1, 2, and 3 due to error codes of P300, P301, P302, P303, and P1349. I also cleaned up the front solenoid and both filters.

Almost as soon as I went for a test drive uphill the engine light began blinking. I drove home immediately and checked the codes. I still have P300, P301, and P302 but P303 and P1349 did not appear. There also was some smoke near the front of the engine. It looked very much like burning oil. I noticed a little tube in that area and wonder if excess oil if being directed out?

Upon reading my first post I realize an obvious mistake. P301 and P303 pertain to the rear bank of pistons, but P302 pertains to the front bank. Getting the rear VVS may have not been enough. Or, is there a more likely explanation for error codes (P300, P301, P302, P303, P1349) then and error codes (P300, P301, and P302) now. Should I buy the left (front) sensor or go a different route? I know the typical answer is to replace the coils. Is it normal though for two sets of coils to go bad at the same time?

Any help would be greatly appreciated.

Thanks,

Marc

shark13

I was able to narrow down problem to a spark plug in cylinder 2. Ten dollars later all is back to normal. I understand there are a lot of threads and appreciate the help I have received over the years.

Marc

owenstrawn

Very interesting info, seems odd that all those codes amounted to a bad plug!

shark13

I think there were two issues. I believe the right (rear) variable speed sensor was kicking on the P300, P301, P303 and P1349 codes and the spark plug was kicking on the P302 code. Replacing the variable speed sensor (listed in previous post) initially caused just the P1349 and P303 to disappear, leaving only the codes P300, P301, and P302. I had read that sometimes a single cylinder can cause error codes to appear (incorrectly) at other cylinders that are not affected. After reading this I did another short test drive and re-read the codes. This time only the P302 appeared. Then I swapped coil locations to narrow down the problem, cleared the codes, did a test drive, and re-scanned the codes. The code P302 remained which left the spark plug as the primary culprit. I replaced the plug and all was well.

Lexmex

Those plugs can get out of gap and throw a code. I saw it using Denso plugs when I was in Mexico and switched to a pregapped Torque Master plug, http://www.extremespark.com/

I get a lot more power out of these plugs, plus can keep them in the vehicle longer. Never had issues since.