Oxygen Sensor questions

[RyDeFly]

My 1988 Turbo failed emmisions (5 times higher than what it should have been) and the mechanic I took it to said that the oxygen sensor needs to be replaced, which he can do for $315. o_O
The Toyota dealership can get the part and install it for $240...
I was under the impression that O2 sensors were like $40....

My question is, do I HAVE to use a special 1988 supra sensor, or can I buy a generic sensor? Where is it located in the car, and can I replace it easily myself?

The mechanic also said that the inside of the intake manifold has heavy carbon deposits, and they can clean it out for $170.....reasonable or not?

Thanks guys.

[kewlcoconut]

omg do NOT go to your mechanic or the dealership. they are ripping you off by over $200. you can EASILY do this yourself.

you just need an O2 sensor for an 88 turbo. the turbo and NA supras are different. the turbos have a 3 wire sensor and the NA has a 1 wire. make sure you get the 3 wire replacement. from what i know, the Denso 02 sensor is the 3 wire one and the Bosch one is 1 wire. they run for about $50 or so. And it will take you about 5 mins to put in.

just look under the hood on the passenger side. In my NA the o2 sensor is on the headers. on the turbo models i believe the o2 sensor is on the downpipe. but still reachable from the passenger side by the intake.

this will take you 5 mins.....super easy.

go to your local auto place, and try and look for a carbon cleaner to spray into the intake. i think there is a product i heard some people talking about a while ago called seafoam? im not quite sure.

but seriously, do not go to your mechanic or dealership for the o2 sensor. you can save over $200.

[j3pz]

out of curiosity, how do they know you got carbon buildup in the intake? and yes you would get ripped off 200$ for this

[Isphius]

How would carbon even get into the intake? unless you car backfires everyday. I went to meinike to get a 4 wheel alignment and they told me i needed new wheel bearings on all 4 wheels. 75$ each for labor and 60$ each for the bearings and grease seals. so i basically gave them the finger and never went back there. I went to a local shop around my house and they charged me 60$ for the 4 wheel alignment and now its fine. lol. The only reason i did this was because my rear wheel was misaligned, one of the arms was out of adjustment. I would also say just buy the oxygen sensor...i changed it myself in 10 minutes, and i have mechanical experience but never changed an o2 sensor. Just unplug and unbolt the old one, change the plug to the new one, shrink wrap the connection, and bolt it back on. my car actually seems to have a little more power and run a little smoother right through 2500~~3500.

[RyDeFly]

I was mistaken, there was no carbon in the intake....

Mechanic wanted to clean out the fuel line because of the large amount of carbon deposits from the Supra running extremely rich from the bad o2 sensor. Is this also something I could do?

>>the Denso 02 sensor is the 3 wire one
I'm assuming Denso is aftermarket, or least not OEM, right? Where can I get those? The actual Toyota oem part is $154 and I have to order it.

>>Just unplug and unbolt the old one, change the plug to the new one, shrink wrap the connection, and bolt it back on.
How do I shrink wrap a connection? Does it involve actual shrink WRAP? Heh, sorry I've never heard of that before.

Mechanics also said that the Turbo hose is loose i.e. not connected....I was under the impression that the turbo had PIPES, not hoses..

My throttle linkage assembly is messed up, and my car idles at 2500rpm, anybody have any experience replacing one of those?

[mrnickleye]

Trust me (see my profile), you can get an aftermarket 3-wire 02 for about $75. Bosch is the most popular at the parts houses. You can get one with the oem plug already on to just plug-n-play.

You may want to spray some WD40 (or similar) on the threads a few times and hours before removing it.

If your mech. said fuel 'lines', (carboned up) get a new mechanic, he IS ripping you off, cause that just won't happen. Also, we only charge $65 labor to replace the 02. (and we also re-check everything to make sure you are gonna pass the test).

It is very true that carbon builds up on the inside of the intake manifold. This is due MOSTLY from the EGR system feeding exhaust gasses into the manifold. It also builds up on the intake valves.

Maybe he meant that the carbon is built up in the egr passages, and therefore the egr system is not working, and will cause the NOx to be too high.

I would ask around (friends, family, co-workers, grocery store clerks, etc) for a recommended shop to check out your car, and make some of the repairs if you can't. Cleaning the egr passages is work, but easy, but does take some mechanical skill, and knowing what to remove and clean.

If you idle is high, you WILL fail the test. That sounds like other issues. How do you drive with that??

[RyDeFly]

Alright, I'm going to buy a Denso o2 sensor over the internet, but is the Universal one ok? That just means I have to splice and stuff right?

Denso numbers
Universal part#:234-3050
OEM is 234-3051


The OEM Bosch sensor for my car is a single wire.....went to 3 different auto parts stores and they all came up with the same thing, all for the turbo, all single wire. And the Bosch part looks inferior to the Denso.

[kewlcoconut]

your car is a turbo but is single wire? i thought turbos were 3 wires....weird.....but anyways, yea go with denso. i went to an auto part store and got an NTK o2 sensor. same people who make NGK spark plugs. it looked like a really good o2 sensor. and i didnt have to splice anything. came with the connector.

let us know how yours goes.

[brad mccarty]

I have a 88 supra turbo and the o2 sensor is a 3 wire do not get the universal one for a turbo, it will help u about as much as keeping youre old o2 sensor in......

[rnoswal]

It really helps to know exactly what you need from a parts store. It is best if you can take the old part in for reference. If you find a parts house that finds what you need and gets it right, always go back to them. Splicing wires is fine if you know how to solder or can make sure you use a good solderless connector, but if you aren't sure about your capabilities, then go with the o2 sensor that has the right connectors.


I don't understand about why you are having the problems. I use many different part stores around here and shop till I get the best price, or if anyone even has the part I need. I almost always go with aftermarket parts, especially with the lifetime guarantee, but I have noticed on a couple of Supra's I have bought, the the previous owners went religously to the dealer and most of the parts are better made, it's just that they are too damn expensive! But that is what you have to decide on. If you can find a place that doesn't seemed rushed and can spend time to help you with what you need, you will come away with the right part or at least pointed in the right direction.

Russ