Check engine light

[Firetacoma]

It came on a couple of days ago. Didn't have a chance to get it checked. Today driving home it shut off by itself. I didn't know they did that.

?

[Mythica]

o2 sensor might be going dead.


They act wierd, i have had my cat off my truck for a while, i have started it and let it run for up to about 20min at a time and i never once through a CEL. So i dont understand the o2 sensors completely. As soon as i started the truck with no cat or muffler the light should have come on, but it didnt.

[Firetacoma]

o2 sensor might be going dead.


They act wierd, i have had my cat off my truck for a while, i have started it and let it run for up to about 20min at a time and i never once through a CEL. So i dont understand the o2 sensors completely. As soon as i started the truck with no cat or muffler the light should have come on, but it didnt.

I talked to a buddy of mine who is a mechanic... I guess some codes are soft and others are hard... the soft ones will shut themselves off if the fault goes away. I'll keep watching it I guess!

[RedRunnertc]

While the light is off, the code is still stored. Run by a vatozone or the like and they can pull it.

Might just be your gascap not tight enough.

[crawyota]

While the light is off, the code is still stored. Run by a vatozone or the like and they can pull it.

Might just be your gascap not tight enough.

my light is on , now , and has been fora few weeks, i tried the gas cap , and even unhooked the bat. but it eventually comes on , then i was thinking it might be the cat , since the bracket that holds it up broke.

[RedRunnertc]

Why guess? It's easy to pull the code:

http://personal.utulsa.edu/~nathan-buchanan/93fsm/engine/85diagnosi.pdf

[ike]

I have had mine come on and go off due to a gas cap, and also due to a TPS going bad. Get the code read and you wont have to guess what part you should replace.

[tacotoy]

read the code.... mine showed TPS problems.... adjusted the cables from the cruise control and the pedal and no now more problem.... they just get streched out over time. it was about 1/2 a thread of adjustment

[Firetacoma]

read the code.... mine showed TPS problems.... adjusted the cables from the cruise control and the pedal and no now more problem.... they just get streched out over time. it was about 1/2 a thread of adjustment

Which brings up another issue... my cruise control doesn't work. I turn it on, the light comes on... I try to make it do the whole cruise thingy and whamo blamo nothing.

[ziggy428]

whats funny is if it has some kind of short in cruise control. When driving below 25 mph mine will sometimes go from full throttle to nothing repeatedly and in fast cycles. That turns some heads.

[fondigley]

My CEL popped back on Monday and I stopped by Checkers and read it yesterday and it said 420 again. Damn Cat or O2. Guess I need to get it looked at.

[tacotoy]

Which brings up another issue... my cruise control doesn't work. I turn it on, the light comes on... I try to make it do the whole cruise thingy and whamo blamo nothing.


light come on after you try to use your cruise control?

[Firetacoma]

light come on after you try to use your cruise control?

Nope.

[tacotoy]

hmmmm.... mine would do it randomly and then i finally figured out that it was the cruise control cable that was causing most of my issues

[Well-Strung]

Hey I get the good old 0420 errors too.... Replacing the o2 sensor this weekend and checking for exhaust leaks.

[Firetacoma]

Ok, it came back on.

Went to checker and pulled the code: P0133
O2 circuit slow response, bank 1, sensor 1

So how do I replace this baby? Pics help!

[Blowntaco]

Ok, it came back on.

Went to checker and pulled the code: P0133
O2 circuit slow response, bank 1, sensor 1

So how do I replace this baby? Pics help!

It will be the sensor in front of the cat or closer to the motor. There will be 2 12mm nuts holding it on, will probably want to spray them with WD-40 or some kind of penetrating oil, you can run the engine for a bit to warm them up but don't burn yourself as it gets very hot fast. Follow the wire to find the connector, automatic trans it will be on the side of the trans, manual will be on the top of trans in front of the shifter. Squeeze one side of the connector to release the connector from each other. Make sure that you replace the gasket for the sensor when you do this. Then just simply reverse order to install. You can reset the light by removing the 20amp EFI fuse in the engine compartment for about 30 seconds, then put it back in and start engine. Hopefully this helps, I don't have any pics to show you sorry. I forgot the sensor will be on the exhaust pipe on the passenger side basically just in front of the door.

[mrdoug]

With the caveat that I snapped a bolt that's going to cost a couple bucks to fix I'll say it's not too hard, but that O2 sensor is expensive. Sensor 1 bank 1 is the sensor up above the first cat closest to the exhaust manifold. 2 Bolts, pull the sensor, unplug it (hint, remove the plug mounting bracket makes it 100 times easier), put in the new one (make sure you get a little gasket with the sensor, one of mine came with it, the other didn't) bolt it back down, plug it in, drink beer.

Everyone I've talked to has had trouble breaking the bolts loose. I found that both soaking it in pb-blaster and heating the exhaust up makes it easier. But then you're working around a hot cat. I found putting a piece of cardboard on the cat/pipe and wrenching it helped reduce the burning (note I didn't say eliminate, but you might be more graceful than I).

I did both my sensors last Friday. One was cake (30 min in and out), the other started stripping aobut 3/4 of the way off, and snapped when I tried to lower it back down. I don't believe I did anything wrong, but then I failed so your mileage may vary. Perhaps one of the others can give you a better tip.

[Firetacoma]

Thanks for the replies.

I think I can handle this... damn, the part is 117 bucks at napa!

It must give a bj while it senses O2.

[Firetacoma]

It's finished!

About a 40 minute job, including going to Checker to buy the part.

Couple of interesting things:
I think I broke the plug mount from the tranny case rather than unbolt it. It just kinda kept coming as I tugged GENTLY (I swear).

The wire on the new one is quite a bit shorter... like it's kinda tightish... and the sensor head looked different than the old one?

But I pulled the EFI fuse for a few seconds, the truck started up without the CE light, and it seems to be idling better than it did before.

[RedRunnertc]

Hopefully you got a Denso or NGK (box will say NTK) and NOT a Bosch one ... lots of reports of the Bosch ones not working quite right with the ECU.

BTW, URD has good prices on O2 sensors

[Firetacoma]

Hopefully you got a Denso or NGK (box will say NTK) and NOT a Bosch one ... lots of reports of the Bosch ones not working quite right with the ECU.

BTW, URD has good prices on O2 sensors

Of course I got bosch! haha

I guess I'll see what happens with it. So far it's working great! The truck hasn't run this smoothly in a while. Maybe my gas mileage will go up too?

[mrdoug]

Hey, if that plug mount is busted, you might want to make sure it doesn't have any possibility of coming close to the exhaust.. Troy had some fun with that just a few weeks ago.

[RedRunnertc]

No shit.

But after fixing it, the truck is running much better. Last three tanks after fixing it have been 19.9, 16.5, and 20.5 MPG - beats the pants off the 10-12 MPG I WAS getting with the bad wire!

[Firetacoma]

No, it's still tucked way up, just not attached anymore... with the tightness of the wire, I think it'll be fine.

[RedRunnertc]

Don't think - KNOW.

It's kinda PITA to fix.

[Firetacoma]

Don't think - KNOW.

It's kinda PITA to fix.

I can't know for sure... but it's in a position that unless the plug comes apart, it can't touch the exhaust... There isn't enough slack for it to drag down on it's own... unless another hanger somewhere gives up the ghost.

[mrdoug]

You gotta love that ol BOSH "you don't need no stinkin OEM part, we have a one size fits all".

[RedRunnertc]

Well, that's better than "I think" - if it's going to take an unusual set of circumstances, then it'll be OK!