Help!

[perkelerttu]

I have litle problem with my car.:aigo:
how to check the o2 sensor, i think its broken
but it dont give any codes.
and car runs very rich:1zhelp:
somebody please help!

 

[GrimJack]

http://www.cygnusx1.net/supra/library/TSRM/fi/FI_119.html

 

[jetjock]

I doubt your problem is O2 sensor related because:

1) The engine will run only slightly rich with it bad or disconnected, at about a lambda of .95

2) The sensor is monitored 3 different ways and can set 3 different codes, none of which you claim to have.

But check it the way Grim pointed you to. Look for at least 8 cross counts in 10 seconds but more importantly look for an average of 450 mv. If it's not cross counting note the voltage it's stuck at and let us know. You can also check the sensor off the car with a propane torch. Look in the tech tips section for instructions. Based on what you said I'd be surprised it turns out to be your problem though

 

[GrimJack]

My guess would be a boost leak after the AFM, personally.

 

[jetjock]

I bet you're right Grim. As I mentioned in another post you can cheat on lots of stuff but the airflow thing will get ya every time

 

[GrimJack]

The only doubt in my mind is because this guy is from the Finland club, and these guys are right up there by the Aussies when it comes to being nuts about their Supras. In the past they've always been a fair bit more competent than the average North American Supra expert, I'd be rather surprised if they missed a boost leak...

Hopefully he'll come back and let us know what the issue was.

 

[perkelerttu]

The only doubt in my mind is because this guy is from the Finland club, and these guys are right up there by the Aussies when it comes to being nuts about their Supras. In the past they've always been a fair bit more competent than the average North American Supra expert, I'd be rather surprised if they missed a boost leak...

Hopefully he'll come back and let us know what the issue was.

I let you know when i get problem solved

 

[perkelerttu]

The only doubt in my mind is because this guy is from the Finland club, and these guys are right up there by the Aussies when it comes to being nuts about their Supras. In the past they've always been a fair bit more competent than the average North American Supra expert, I'd be rather surprised if they missed a boost leak...

Hopefully he'll come back and let us know what the issue was.

OK now i found what the problem was! o2 sensors signal wire was broken
but im confused why it didnt give any codes???

 

[GrimJack]

Not all of the ECUs will throw a code when the O2 is malfunctioning. My Canadian 89 does, but I know several people who have not run into this.

 

[jetjock]

Oh, so now you tell me Grim . You're right, I checked the books. O2 codes (21, 25, and 26) are set only in US, Canadian, and OZ models. Damn internet and it's worldwide capabilites . By set I mean light the MIL. As far as I can tell they should still be set in memory but the books aren't clear on that. Funny though, mine runs only slightly rich if I simulate this fault.

 

[perkelerttu]

Not all of the ECUs will throw a code when the O2 is malfunctioning. My Canadian 89 does, but I know several people who have not run into this.

Ok! next time i know that...thanks!

 

[GrimJack]

JJ, you're the reason I know this! I know from experience that an open circuit on the heater element will set a code on my car, ran into that when mounting my wideband. Then a discussion with you a while back explained that some cars don't get this... so there had to be a difference.

Exactly what it was I didn't know, thanks for looking it up for us!

 

[jetjock]

The books have enough notations and footnotes it's hard to keep it all straight so I tend to forget them. Near as I can tell all of differences apply only to diagnostic routines and concern emissions rules. Makes sense as the engine would need to run pretty much the same everywhere.

However it's clear the intent of the diag coding for the US, Canada, and Oz is to inform the driver of problems that increase emissions. Cali cars are even more stringent in this regard. These differences all involve lighting the MIL but I'm surpised to find DTCs are not still set in memory for all cars. The books imply they are but aren't 100% clear. He said he didn't have any codes though so there you have it I guess.