geekrunner

Hello all! I've had this car nearly three years, and about 18 months ago we began getting an intermittent CEL along with VSC and VSC OFF lights. It seemed that when the lights were off, the car ran OK, but when the lights were on, it ran a little rough.

Purchased car with 201,000 miles and it has 258,000 miles now.

Now, in the past few months, the car rarely shifts into OD, and occasionally will not downshift to low gear. My wife drives this car to Louisville to work, a 3 1/2 hour round trip and I don't want a breakdown. When she has had trouble, I have had her stop, shut off car for a minute or two, then restart, then it will shift into OD so long as she doesn't get into stop and go traffic. Mostly she drives highway speed between Indianapolis and Louisville.

I bought a scanner/code reader, connected it and this is what I got:

P0125
P0325
P0330
P0420
P1133 (showing as a pending code also)
P1135 (showing as a pending code also)
P1349

I'm a DIY guy and have done extensive engine work on my 95 Honda Civic (318,000 miles and counting) so I'm confident I can do any repairs of this nature.

Based on my research on this forum, and to get my best bang for the buck, this is my plan:

Replace A/F ratio sensors on both banks (1133, 1135)
Replace the knock sensor harness(es). (0325, 0330)
Clean MAF sensor, intake manifold and plenum (0420)
Clean or replace right bank OCV (1349)
Clear codes, drive car, scan for pending codes again.

Questions for the Forum:

• Would you do anthing differently than what I described?
• Is there just one knock sensor harness, or is there one for each sensor?
• Considering I'm doing my own work, is it worth the gamble to just replace the knock sensor harness instead of also replacing both sensors? I ask because the CEL, VSC OFF and VSC lights were intermittent issues at one time, however now they stay on all the time.

Thanks for any advice you can give! Dave

lostape45

I am by far no expert on this topic but merely speaking from personal experience. I would replace the OCV first imo. I had the same code as you (P1349) and my transmission did the same thing when driving my car. But I also had codes for cylinders 1,3,5 and a random cylinder misfiring and oh man could you tell, my car sounded like a dirtbike when it was running. I think that is what is causing your transmission to act so odd, as mine did the same thing. I think in all honesty that the car is forced into limp mode when it can't fire the cylinders correctly, causing the trans to try and safe itself.

I can't shed very much light on the other codes as I haven't had any of those, but I would definitely start with the OCV. I would just replace it outright as they aren't terribly expensive. Start with that and let me know where you end up.

geekrunner

Thanks lostape45, I will be working on that today. I will remove it, try to clean it first. If I somehow break it, I can get one from Autozone today. I will also clean the MAF sensor and throttle body, add Seafoam to oil and gas, change air filter, reset codes and take for a drive, then change the oil.

Dave (geek)

geekrunner

OK, got the oil and filter changed, cleaned the MAF sensor, cleaned the OCV filters (did not remove the sensors themselves), cleared the codes and test drove. Car would shift to OD on the first startup, but once I slowed to a stop at an intersection, it would not shift to OD after that. Then about five minutes later, the CEL and VSC OFF lights lit up. Immediately checked the codes and got P0125 stored, and no pending codes. Drove at highway speed (65mph at 4000 rpm) for about five minutes, stopped and reran codes, got the P0125, P0330, then pending codes of P1133, P1135.

Next move, replace knock sensors/harness, and right A/F ratio sensor.

Dave

geekrunner

Happy New Year!

I finally am to the point where I can begin work. Since my last post, the ES has gotten worse, even though it is not throwing quite all the same codes. I connected the code scanner yesterday, and now these are the codes that appear:

P0125
P0325
P0330
P1135 (showing as a pending code also)
P1346
P1349

I'm getting more rough idle now, which prob is related to the P1346 code, which is new code to appear.

I've already gathered the two Denso knock sensors, new harness, coolant bypass hose, and socket to remove the rear upstream air/fuel ratio sensor. I still need to score the correct a/f ratio sensor, gasket kit, right VVT sensor, PCV valve and grommet, spark plugs, coolant thermostat, and new coolant.

But first, I need to clean out my garage and rent a salamander. It's pretty cold outside!

Dave

geekrunner

OK, garage is cleaned out, work bench cleared off. Kerosene heater is operational. Mrs. Geekrunner is out of town working for the past week, won't be home till Friday afternoon. I'm off work the next two days. Outside temps should be in the mid-30s tomorrow.

I have all the parts I need for now: two Denso knock sensors, wiring harness, six spark plugs, Denso Bank 1 air/fuel ratio sensor, Denso Bank 1 VVT solenoid, intake manifold and plenum gaskets, cylinder cover gaskets, PCV valve and grommet, thermostat and gasket, coolant bypass hose, and appropriate tools.

I'll attempt to write down my disassembly steps, and take a few pictures. Work begins tomorrow morning. Wish me luck!

your geek

geekrunner

We have a 99% success! I finished the work last week. I took several pictures but have not had a chance to process and post them. I also attempted to write down my disassembly steps. I got most of them, and can fill in the reassembly steps (basically reverse of disassembly).

Progress report:

Car drives much better! No hesitation off idle, and shifts consistently into OD after proper warm-up.

I had a problem with one spark plug acting like it was cross-threaded. It was very difficult to back out, so instead of possibly breaking it off in the head, or making it impossible to thread in a new spark plug, I opted to leave it in. It was the front right cylinder, as you face the engine.

I lost one of the little o-rings from the tip of a fuel injector, so I bought a whole new set and replaced them all prior to reinstallation.

No coolant leaks, no extra parts!

One issue that occured, was after about three days, on a normal drive, the CEL came on. Code scanner showed P0420, which was a code it displayed back in August, but was not right before I began work. Catalyst System Efficiency Below Threshold (Bank 1). I cleared the code, and drove it for about 25 miles, then the VSC OFF and VSC indicators lit up, but not the CEL. Ran scanner, and P0420 only comes up as a Pending code. Car still runs great. Because the code doesn't immediately come up, could it possibly be from an occasional misfire from the old spark plug I didn't remove? I'm not really in the mood to replace any O2 sensors yet, and have no way to test them. Unless someone has any sure-fire answers, my tendency is to just drive it as-is until I decide to try to remove that last plug. I don't want to do it unless I can be prepared to remove the head in case I break off the plug or can't thread a new plug in.

I appreciate your thoughts!

geek

ES300NZ

totally FYI:


I like to use anti-seize on spark plugs.
http://www.antiseize.com/index.html

tomf

NGK recommends NOT using anti-seize, due to the potential of over-torquing the spark plug.
http://www.ngksparkplugs.com/pdf/dyk_5points.pdf

geekrunner

Thanks for the video reference! I did use some anti-seize on the five plugs, but I used it sparingly. I will try again later to remove the last plug, and use some PB Blaster first to help it along.

BTW i've cleared the P0420 code twice, and it reappears after about 30 miles of driving. Car still runs great though! I have previously cleaned the MAF sensor. It seems odd that I get the P0420 code pretty consistently now, while it wasn't showing up when the other codes were occuring just before I replaced the knock sensors and A/F ratio sensor.

geek

ES300NZ

maybe its genuine.

PFB

Did you check for exhaust leaks, including the flex pipe?

Phil

geekrunner

I have not. I need a mental break from the car, so when the weather warms up in the spring, I can get it back up on the stands and look underneath. For now, it' only a minor nuisance. The car runs better than it has in a couple of years!

Maybe I misspoke when I said "pretty frequenty". It actually has been occuring, but not at any regular interval, such as a certain number of miles, or minutes of driving, or if it occured during sustaned highway miles. My thinking is that it is less likely to be the fore/aft o2 sensors. If one of them has failed, wouldn't it throw some hard code rather than a soft one? If I ultimately replaced the catalytic converter, would I need to also replace the two o2 sensors too?

geek

PFB

You don't even have to lift up the car to look for exhaust leaks.

All you need do is start the car, cover the tailpipe completely with the palm of your hand, and listen for the sound of escaping exhaust. If there are no leaks, the engine may (but may not) stall.

When you are ready to try it, a helper observer can be usefull to identify the source if a leak exists.

If you can do this test with both a cold and a hot engine it's even better.

Shouldn't take you longer than 10 minutes.


Phil

geekrunner

Thanks PFB for the advice! I'll try that this weekend.

After I cleared the P0420 code for the second time last week, I thought I would try running 93 octane Super Unleaded wiht some Lucas fuel injector cleaner. After three days of in-town driving, no recurrenc eof the CEL. We'll see how that goes.

geek