josediablo

Ten days ago I had a check engine light come on. Took it to the Repair shop and it came up as p1133- Air Fuel Ratio Sensor. Since I was getting my steering rack and pinion and struts done at the same place, he said he would do that last. Anyway I took the car home for the weekend and last Friday as I was driving to the shop I had a check engine light come back on, after almost three days of driving since p1133 was reset. Prior to the check engine light coming on I was doing about 65 mph and noticed a braking motion with the vehicle. This happened twice then the light came on. Took it to the shop and this time it was p1155....VVT-OCT. Anyway since the sensor I got was not the right one. I was told to take the vehicle and come back with the right one. When test driving the vehicle after strut and rack and pinion replaced, the check engine light came back on and this time it was p1154. Anyway since the guys are busy I brought it home and this morning I checked the front bank OCV and filter and the rear bank OCV and they all look pretty clean. I was unable to check the rear bank OCV oil filter, as I did not have a breaker bar to get the 14mm nut loose. I cleared the check engine light (battery negative) and drove to get a breaker bar. Vehilce drives great, no problems, Returned home and as I rounded the corner the check engine light has come back on. I don't have a OBDII scanner and so wondering what the code is this time around.

Has anyone had the same cycle of emission codes ight up? If so what should I do? I will check this check engine light tomorrow and make a decision. My gut says change the A/F sensor that came up first, since the OCV on both banks have no sludge build up and the filter in the front bank is clean.

As info. I have 210K miles on the vehicle. Aout 65k miles on the engine (replaced two years ago with new timing chain and low mileage (45kmiles) engine. I have never replaced either of the oxygen sensors in 8 years since I have had the vehicle.

Any suggestions, experiences, advice is much appreciated. Thanks all.

Baetke

OCV's can be clean and check out electrically but still be bad. Fairly simple and inexpensive fix to do. Have you had "hard braking" because of low vacuum caused by the OCVs? This is a sure diagnosis. Good chance your A/F sensor is bad also at this age. I recommend investing in a code reader so you can diagnose some of this yourself. They are not very expensive and with a car this old you will probably get more use out of it.

Baetke

carguy07

p1133 is B1S1, p1155 is B2S1, there is no p1154 that I know of on this car??

My guess would be that a new Denso in each bank clears the problem.

Why are you looking at OCV at all??

josediablo

Thanks guys. This one's a doozy. What came first, the chicken or the egg!!. Sorry @Carguy07, my bad, it should be p1354 not p1154. p1354 is OCV bank 2.

Please correct me if I am wrong, but these codes, all coming up in series almost in quick succession tell me there is a related problem of improper combustion. The VVT increases engine torque and horsepower while addressing California environment emission limits. It's like advancing combustion by early intake valve opening or retarding combustion by later opening to reduce horse power. So if p1354 (OCV Bank2) is the culprit, then I can see the air/fuel ration sensors start to complain almost immediately. Also I experienced the engine hard-braking twice (in a short spell) before the p1354 light came on.

Anyone agree? I will check out the code this morning and see what i have. Will get me an OBDII from one of the local auto-parts dealers.

Baetke

I agree. See my post #2.

josediablo

Here's an update after the OBDII scan.

1. p0125- Insufficient coolant temperature for close loop fuel control
2. p1155 (pending) - Bank 2, Sensor 1
3. MIL On/IM Montiors - catalyst, evap, O2 sensor, misfire, fuel, compr, O2 htr.

I erased all codes and decided to go fill up the tank as it showed close to end (2 gls left). Drove home 10 miles, so far so good.

I had read one of these threads where a similar set of codes came up and the gentleman changed sensors, and OCV etc., only to have the Check Eng. light back on. He filled up the tank from a different gas station and VOILA! the light never came back on. So I filled up the tank and ensured the gas cap was clicked 3 or 4 times shut.

If the codes come back on, I think I'll just change both A/F ratio sensors. In the interim, I hope that it was a bad load of fuel. I've seen bad fuel damage engines on big vessels when I used to sail deep sea many moons ago!! Any comments, input is much apprecaited. Thanks guys.

josediablo

Drove the car today barely 5 miles and chk eng. light back on. Thanks Baetke for suggesting I buy a code reader. The codes now in there are:

1. p0125
2.p0171.. Bank 1 too lean
3.p1153 x twice.bank 2 sensor 1

Which is the best place (other than the dealer) to buy Denso A/F sensors? Anyone who has had to buy them have a preference?? Thanks guys. Appreciate your help.

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