Update on lean codes

mcate

mcate

Registered User
Car was frequently throwing a CE light last week. I was getting codes 136 & 172, lean on both banks. I fixed a vacuum leak, the purge valve on the charcoal canister, but I was still getting the light frequently. But after driving the car to & from work a couple of times, I stopped getting the light as often. Haven't gotten it at all the last couple of days.
So last night a friend came over who's a mechanic at a local Ford dealership. He hooked up a scanner & looked at "streaming data", & the only thing that didn't look right was the bank one 02 sensor wasn't switching right. We left the scanner hooked up & drove the car around, & the sensor switched much better while driving. He said everything looks right while driving. I even got on it & all the readings looked good. He thinks I might have a vacuum leak on the passenger side somewhere. We're going to take it in to his shop on a Saturday soon & try to find the leak.
 
Mike - that's very interesting. My '93 5 speed would throw a CE light only when I shifted from 1st to 2nd. Subsequently I pulled the plugs & 02 sensor on the one bank (code 172 I recall) and the sensor was white coated + the plugs had some fine gray ash on them. I too looked for a vacuum leak and resealed the IC tubes, but no improvement. I replaced the one 02 sensor & the plugs and the CE light never re-appeared. However the car would then stall at idle and only re-start after it cooled off. Finally I noticed that the balancer had a slight wobble and now it will still start and rev high but the idle vacuum is only 7-10 ". Obviously the balancer is shot, but I'm still concerned about the vacuum. One member's theory is that because it's been running lean for a while it may have burnt a valve. Maybe your mechanic would have some thought on this one.


kg
mcate said:
Car was frequently throwing a CE light last week. I was getting codes 136 & 172, lean on both banks. I fixed a vacuum leak, the purge valve on the charcoal canister, but I was still getting the light frequently. But after driving the car to & from work a couple of times, I stopped getting the light as often. Haven't gotten it at all the last couple of days.
So last night a friend came over who's a mechanic at a local Ford dealership. He hooked up a scanner & looked at "streaming data", & the only thing that didn't look right was the bank one 02 sensor wasn't switching right. We left the scanner hooked up & drove the car around, & the sensor switched much better while driving. He said everything looks right while driving. I even got on it & all the readings looked good. He thinks I might have a vacuum leak on the passenger side somewhere. We're going to take it in to his shop on a Saturday soon & try to find the leak.
Click to expand...
 
Joisey Jim said:
Mike - that's very interesting. My '93 5 speed would throw a CE light only when I shifted from 1st to 2nd. Subsequently I pulled the plugs & 02 sensor on the one bank (code 172 I recall) and the sensor was white coated + the plugs had some fine gray ash on them. I too looked for a vacuum leak and resealed the IC tubes, but no improvement. I replaced the one 02 sensor & the plugs and the CE light never re-appeared. However the car would then stall at idle and only re-start after it cooled off. Finally I noticed that the balancer had a slight wobble and now it will still start and rev high but the idle vacuum is only 7-10 ". Obviously the balancer is shot, but I'm still concerned about the vacuum. One member's theory is that because it's been running lean for a while it may have burnt a valve. Maybe your mechanic would have some thought on this one.


kg
Click to expand...

I'll let him know about your symptoms this weekend when I see him. Sure hope it's something less serious.
I'm gonna have him pick me up a set of OEM 02 sensors & I'll put them on over the weekend. I also ordered a set of Tbird 88's reusable IC gaskets this morning. Tired of wondering whether the copper RTV set up right or not!
 
Thanks Mike - I'm out of the teflon seal tape myself now and, I think Wynn's gaskets are definitely the way to go. I'm gonna order some too, because I still have a set of his ported headers to install.
Jim.

mcate said:
I'll let him know about your symptoms this weekend when I see him. Sure hope it's something less serious.
I'm gonna have him pick me up a set of OEM 02 sensors & I'll put them on over the weekend. I also ordered a set of Tbird 88's reusable IC gaskets this morning. Tired of wondering whether the copper RTV set up right or not!
Click to expand...
 
Picked up a set of OEM 02 sensors & the car seems to be running fine. Looked at the data on the scanner & both 02 sensors are switching within the same ranges as one another. Looks good so far.
 
You must log in or register to reply here.
Back
Top