CEL appear and disappearing

Joefishizzle · 04-26-2012, 11:10 PM

So after about 15 mins of driving or about 20 miles my cel comes on, however after I turn the car off and come out again. No codes.....
I've checked my battery not like its resetting. Previous codes were 51, my idle turns to shit when it comes on. Idles at about 1100.
Any suggestions?

cre · 04-26-2012, 11:29 PM

Could be knock. Not all runtime errors are recorded and from what I understand some require a certain threshold to be surpassed in any given instance before it's recorded. There is no code for "OMG there's a hole in the #1 piston and your rods are a knockin!". You can try driving around with the diagnostic mode set and see if any additional codes show up. Naturally there will be a code 51.

Power loss at the ECU to the point of clearing the codes is a possibility but usually this isn't consistent and you'll see a code for inconsistent power show up sooner or later.

Code 51 is just indicative of the IDL switch being open the A/C circuit reporting as "on" and it clears as the trigger condition is resolved. So, it'll show up it you step on the throttle, have the A/C on or the TPS is misaligned but once the condition is remedied it'll go away after a few seconds.

Joefishizzle · 04-26-2012, 11:49 PM

Well as far as vocal noise I can't hear a knock. Everything seems to be good. When I got my car the tps was loose so it was moving and my connector is shit, im gonna replace both of those with oem parts from driftmotion since there right down the street....and cheaper than vatozone!!!! Thank you cre. Im gon a jump the block and drive and see what happens.

Joefishizzle · 04-27-2012, 02:40 PM

Okay so codes 21, 31, and 51

21 - I have a brand new o2 sensor
.....so im not sure there

31 - is the afm correct? Now I've read the FAQ section on adjusting. However when you say the screw has to be a certain distance you mean from the top of the screw to the top of the housing or ? I could use some more insight on this one.

Thanks guys

cre · 04-27-2012, 05:46 PM

Quote:

Originally Posted by Joefishizzle

Okay so codes 21, 31, and 51

21 - I have a brand new o2 sensor
.....so im not sure there

Well, I'm not there to look at it for you so get your ass moving and do what makes sense (inspect the connector, wiring, sensor for crap stuck to ir, rattling noises when turned, bad gasket).

Quote:

Originally Posted by Joefishizzle

31 - is the afm correct? Now I've read the FAQ section on adjusting. However when you say the screw has to be a certain distance you mean from the top of the screw to the top of the housing or ? I could use some more insight on this one.

There was another part in that thread which said NEVER TOUCH THIS SCREW! That thread is only there so you can reset the screw is someones f'ed with it. At any rate, even if someone f'ed up the fuel mixture by dicking around with stuff like an idiot it still wouldn't cause a code 31. RTFM for diagnostics on the AFM.

Joefishizzle · 04-27-2012, 06:08 PM

I've checked all that. And I read that as well however the cap covering the screw is missing. So there is another cause for code 31?

cre · 04-28-2012, 12:38 AM

Code 31 is an electrical failure. Nothing to do with the housing or trim screw.

<snip>

Joefishizzle · 04-28-2012, 01:05 AM

Forgot to mention im NA :[

cre · 04-28-2012, 02:34 AM

Oh god... sorry. mixing up posts.... Just trying to check in while dashing from one place to another.

Forget everything except that 31 is an electrical failure. Resetting the idle/bypass air screw isn't going to fix that. Test the AFM as detailed in the TSRM.

Green7mgte · 04-28-2012, 02:43 AM

rotflmao..

04-26-2012, 11:29 PM	#2
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Could be knock. Not all runtime errors are recorded and from what I understand some require a certain threshold to be surpassed in any given instance before it's recorded. There is no code for "OMG there's a hole in the #1 piston and your rods are a knockin!". You can try driving around with the diagnostic mode set and see if any additional codes show up. Naturally there will be a code 51. Power loss at the ECU to the point of clearing the codes is a possibility but usually this isn't consistent and you'll see a code for inconsistent power show up sooner or later. Code 51 is just indicative of the IDL switch being open the A/C circuit reporting as "on" and it clears as the trigger condition is resolved. So, it'll show up it you step on the throttle, have the A/C on or the TPS is misaligned but once the condition is remedied it'll go away after a few seconds. __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

04-28-2012, 12:38 AM	#7
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Code 31 is an electrical failure. Nothing to do with the housing or trim screw. <snip> __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar ---> Last edited by cre; 04-28-2012 at 03:27 AM. Reason: Posted info here that was for another thread.

04-28-2012, 02:34 AM	#9
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	Oh god... sorry. mixing up posts.... Just trying to check in while dashing from one place to another. Forget everything except that 31 is an electrical failure. Resetting the idle/bypass air screw isn't going to fix that. Test the AFM as detailed in the TSRM. __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

04-28-2012, 02:43 AM	#10
Green7mgte Supra Forum Moderator Join Date: Nov 2009 Location: Green-Ohio Posts: 1,297	rotflmao.. __________________ 92 Ma71 7mGTE Auto. SafcII Supra FAQ Supra MKIII FAQ Classified Section guidelines :

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04-26-2012, 11:10 PM	#1
Joefishizzle 3" Exhaust Join Date: Mar 2012 Location: California Posts: 105	CEL appear and disappearing So after about 15 mins of driving or about 20 miles my cel comes on, however after I turn the car off and come out again. No codes..... I've checked my battery not like its resetting. Previous codes were 51, my idle turns to shit when it comes on. Idles at about 1100. Any suggestions?

04-26-2012, 11:49 PM	#3
Joefishizzle 3" Exhaust Join Date: Mar 2012 Location: California Posts: 105	Well as far as vocal noise I can't hear a knock. Everything seems to be good. When I got my car the tps was loose so it was moving and my connector is shit, im gonna replace both of those with oem parts from driftmotion since there right down the street....and cheaper than vatozone!!!! Thank you cre. Im gon a jump the block and drive and see what happens.

04-27-2012, 02:40 PM	#4
Joefishizzle 3" Exhaust Join Date: Mar 2012 Location: California Posts: 105	Okay so codes 21, 31, and 51 21 - I have a brand new o2 sensor .....so im not sure there 31 - is the afm correct? Now I've read the FAQ section on adjusting. However when you say the screw has to be a certain distance you mean from the top of the screw to the top of the housing or ? I could use some more insight on this one. Thanks guys

04-27-2012, 06:08 PM	#6
Joefishizzle 3" Exhaust Join Date: Mar 2012 Location: California Posts: 105	I've checked all that. And I read that as well however the cap covering the screw is missing. So there is another cause for code 31?

04-28-2012, 01:05 AM	#8
Joefishizzle 3" Exhaust Join Date: Mar 2012 Location: California Posts: 105	Forgot to mention im NA :[