three issues 1995 Avalon 89K miles

[mnbipe]

After code po130 and po133 I replaced front and rear plugin 4 wire aftermarket o2 sensors and still have the codes come back Bank 1 Sensor 1 .

Second I checked the plugs that are a Bosh twin tip style. Sorry didnt check the number. I am told it is an aftermarket style. And with only 89K on engine I would belive them to be in good shape. Now Since I have checked them and installed new o2 sensors the engine has a rough idel most of the time. And it ran smooth before I checked them. Any thing I could have done come to mind ?
Coil over spark plugs seam pretty stright forward and a non screwup.

Lastly my dome light wouldnt come on. I replace the Bulb and volt metered the new one too.
The dome light came on after disconnecting the battery for the o2 sensors and reconnect. And now it wont work again. Weird
All the fuses are good and the door switch checks fine.
Not the most important issue.
Thanks Kevin

[pmesfun]

Remove those Bosch plugs and throw them away, and get some NGKs or Denso plugs only. What brand are the O2 sensors?

[mnbipe]

Thanks in progress now.
NGK purchased will install tonight and o2 sensors are from a Discount02 sensor company 4 wire heated with plug ends. They dont have the side baffles but a tip baffle.
Dome light came back on out of nowhere and turns out iwth just a slight deflection it will stay on. flipping back and forth dones nothing. I'll do a complete disassembly of it and carbontet it and make sure connections are sufficiant.

[pmesfun]

Originally Posted by mnbipe

Thanks in progress now.
NGK purchased will install tonight and o2 sensors are from a Discount02 sensor company 4 wire heated with plug ends. They dont have the side baffles but a tip baffle.
Dome light came back on out of nowhere and turns out iwth just a slight deflection it will stay on. flipping back and forth dones nothing. I'll do a complete disassembly of it and carbontet it and make sure connections are sufficiant.

Something about these Toyotas, they don't like Bosch plugs. If the cars runs fine after the new plugs I wouldn't worry about the O2 sensors. BTW, NGK (2978) BKR6EP-11 is the correct plug for your 95 Avalon.

On the dome light that happened to me too recently, stopped working for a month, then two weeks ago when my friends opened the passenger doors it started working again. Weird indeed.

[mnbipe]

New NGK plugs Drove 60 miles on hiway. Did fine except it starts to lope at idel after 15 sec gets progressively worse till the tach is showing a bounce. Accell a thousand and it levels off . Return to idel and it slowly goes back to lope. Shut it off and restart and it purrs till the 15 sec lope starts again. Slow driving is no problem RPMS just need to be above idel to purrr.
AND the check engine light is now back with code P0170 this is a new number now the PO130 and 133 did not come back although it appears to be relitiviley the same Bank 1 Sensor 1 if AutoZone is remotely correct.

[BonzoGonzo]

Before you do anything else... add some lucas or sea foam fuel injection cleaner (as per instructions on the can - they ARE different) and run the gas out. Then change the fuel filter. Then change the PCV valve. Then you'll have a safe starting point...

[mnbipe]

Sounds inexspensive and logical. Done and done. Thanks to you all for the input.
Kevin

[pmesfun]

Originally Posted by mnbipe

New NGK plugs Drove 60 miles on hiway. Did fine except it starts to lope at idel after 15 sec gets progressively worse till the tach is showing a bounce. Accell a thousand and it levels off . Return to idel and it slowly goes back to lope. Shut it off and restart and it purrs till the 15 sec lope starts again. Slow driving is no problem RPMS just need to be above idel to purrr.
AND the check engine light is now back with code P0170 this is a new number now the PO130 and 133 did not come back although it appears to be relitiviley the same Bank 1 Sensor 1 if AutoZone is remotely correct.

Progress! Are you sure it was code P0170? All I could find in the factory service manual was P0171 and P0172.
Screenschot from the FSM. Check all trouble areas if that is the code.


If you're gonna change the PCV valve, get one from the dealer, the aftermarket ones are cheap, when I tried to take out the Beck & Arnely I had installed it snapped in half, it was only 4 months old. I went ahead and got a new grommet and PCV hose as well from the dealer as well.

While you're at it clean the Throttle Body and spray TB cleaner into the IACV port hole as well. Let the cleaner soak in to the IACV for 10 minutes. It will take some time to start the car and will run rough, but it will smooth out, and help the car idle better.

This is my throttle body, you can see the port hole inside the throttle body, spray the cleaner down there.

[chuckoff]

Clean the MAF, IAC valve and get rid of the el-cheapo O2 sensors.

[mnbipe]

I put Denso o2 sensors in front and rear and now am stuck with the Bosh brand o2 sensors that did not work. (Note) that the o2 Bosh style of tip is entirely differant than the original and the Denso looks identical to stock. But I paid $100 for each (set) so could be worse.
Now it idels smooth and no check light.
I made repairs one at a time with advice here on where to start, and it was appreciated.
Thank you all.
Kevin

[BMR]

Excellent!... glad to hear the Denso O2 sensors fixed the error codes.

The dome light being intermittent is probably the door switches. I know you said you checked 'em and they're good. But they commonly get dirty and dusty inside and start getting dodgy. Take 'em out and hose them down with WD40 until they're dripping while simultaneously working the switch plunger. I bet that fixes the problem.

[mnbipe]

Turned out the Dome light itself had faulty contacts and after taking it apart and cleaning them it is fine. The door contacts always tuned on the door lighting so they at least were doing there job.
Thank you for the post.