This is topic 2001 Corolla throwing codes - Fuel System Lean Condition? in forum Tech Talk at Northern California Ford Owners  .


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Posted by 88DroptopGT (Member # 2535) on :
 
I pulled codes on a 2001 Toyota Corolla and it threw "Fuel System Lean Condition" code.

Anyone know what I need to replace? It just happened when I filled up at Costco so I'm keeping an eye on the temp/MPG on this tank.

Is it the regulator (if it even has one)?


[Confused]
 
Posted by Joooestang66 (Member # 2828) on :
 
Check for vacuum leaks. Make sure the air inlet tube is secure, squeeze all the vacuum lines and make sure none are soft and are sealing correctly.
 
Posted by 88DroptopGT (Member # 2535) on :
 
Thanks I'll double check those vacuum lines.
 
Posted by 88DroptopGT (Member # 2535) on :
 
It also states it being in "bank 1" or #1 cylinder so could it be the injector?

Any toyota techs out there?

[Confused]
 
Posted by two-gun kid (Member # 5891) on :
 
maybe the o2 sensor is bad,
 
Posted by Jimbo (Member # 1456) on :
 
Bank 1 refers to the bank of cylinders that is running lean. In this case on a 4 cyl you only have one bank of cylinders. In addition to the vacuum leak check, might also want to check fuel pressure, the fuel filter(pluged filter could make the car run lean) and for any exhaust leaks before the O2 sensor. If all this fails might want to take it to a shop and have them test the operation of the 02 sensor. good luck
 
Posted by 88DroptopGT (Member # 2535) on :
 
quote:
Originally posted by Jimbo:
Bank 1 refers to the bank of cylinders that is running lean. In this case on a 4 cyl you only have one bank of cylinders. In addition to the vacuum leak check, might also want to check fuel pressure, the fuel filter(pluged filter could make the car run lean) and for any exhaust leaks before the O2 sensor. If all this fails might want to take it to a shop and have them test the operation of the 02 sensor. good luck
Yeah i realize bank #1 pertained to the #1 cylinder out of the 4.

I was thinking it could be the fuel injector. It didn't throw an o2 sensor problem (there are separate codes for that in Chilton's.)

Stupid general "lean" code. Her tank also went down in efficiency 10 miles or so total meaning something definetely isn't running right in that #1 cylinder.
 
Posted by Jimbo (Member # 1456) on :
 
Might want to check the plug on #1 and check the resistance on the plug wire and the injector, hopefully the specs are in your Chiltons.
 
Posted by cheap (Member # 858) on :
 
the loss of efficiency (and probably performance, too) will be attributed to the engine's computer kicking the car into a "safe rich" mode to compensate for the lean condition it is detecting. You know, to protect against detonation if you are actually running lean.
 
Posted by biggmatt (Member # 1124) on :
 
i had the same code on my truck...i went to a couple forus and they recommened cleaning the m.a.f. sensor. solved MY problem.
 
Posted by 88DroptopGT (Member # 2535) on :
 
quote:
Originally posted by biggmatt:
i had the same code on my truck...i went to a couple forus and they recommened cleaning the m.a.f. sensor. solved MY problem.
MMM I'll try that. Thanks!
 
Posted by 88DroptopGT (Member # 2535) on :
 
quote:
Originally posted by biggmatt:
i had the same code on my truck...i went to a couple forus and they recommened cleaning the m.a.f. sensor. solved MY problem.
Yeah I checked it out and that was the problem alright. Cleaned it and it's running great!

THANKS! [patriot]
 
Posted by 1FAST89GT (Member # 5071) on :
 
is the light still on? also noticed u said right after4 a fill up. u will get that code if gas up with car running, or do not tightened cap all the way on all obd II cars. just to let ya know [Wink]
 
Posted by 88DroptopGT (Member # 2535) on :
 
Yeah it was the dirty MAF sensor that threw the codes.

I checked for Vacuum lines and everything else checked out.

Thanks though!
 




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