codes 12,21,24,31,51 question about using safc to bypass maf?

turbo87targa

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Nov 10, 2006
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ok so my 87 just popped all 5 of these AT ONCE!
12 - rpm signal
21 - oxygen sensor signal
24 - intake air temp sensor signal
31 - air flow meter signal
51 - switch signal

51 im sure is just the tps out of adjustment (may be wrong)
12 im not sure at all on, car has always thrown that (everytime i have other codes that is) but i really hope it isnt my cps D:

but 21 24 and 31 are all new, and a new afm from toyota is upwards of 700$ :aigo:

is there a way to tune my safc so that my car wont really need my intake sensor or afm? (getting rid of 24 and 31) if im forced to buy a new mafs im just going to save up the extra 400 and go straight to a stinger ems.

any suggestions on what i should do here?

(btw car idles and drives ok, a little difficulty starting sometimes, but normal driving is ok, as soon as i hit 3+psi the car pops waaaaay lean and pulls back hard)
 
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WhtMa71

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You cannot ditch the AFM by way of safc. MAFT-pro can do it however. Check the connections first. Make sure it's actually plugged up, make sure the wires arent corroded or anything. You can check the AFM per TSRM. If it still doesn't work just buy some used electronics from someone on here.
 

Nick M

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turbo87targa;1166401 said:
ok so my 87 just popped all 5 of these AT ONCE!
12 - rpm signal
21 - oxygen sensor signal
24 - intake air temp sensor signal
31 - air flow meter signal
51 - switch signal

Does the car run?

51 im sure is just the tps out of adjustment (may be wrong)

Or the A/C button was on. Or the accelerator was depressed,even just a little when the test was started.

12 im not sure at all on, car has always thrown that (everytime i have other codes that is) but i really hope it isnt my cps D:

Does the car run?

but 21 24 and 31 are all new, and a new afm from toyota is upwards of 700$ :aigo:

First thing is to pull the EFI fuse for more than 30 seconds.

is there a way to tune my safc so that my car wont really need my intake sensor or afm?

No. As he said above, you need it. All the SAFC does is alter the air flow meter signal.

if im forced to buy a new mafs im just going to save up the extra 400 and go straight to a stinger ems.

Just so you know, you don't have a MAF sensor.



(btw car idles and drives ok, a little difficulty starting sometimes, but normal driving is ok, as soon as i hit 3+psi the car pops waaaaay lean and pulls back hard)


How do you know it goes way lean?
 

turbo87targa

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WhtMa71;1166563 said:
You cannot ditch the AFM by way of safc. MAFT-pro can do it however. Check the connections first. Make sure it's actually plugged up, make sure the wires arent corroded or anything. You can check the AFM per TSRM. If it still doesn't work just buy some used electronics from someone on here.

installing a new wire harness here in a few weeks, i think that may be the cause of some of it, if not its needed anyhow.

Nick M: well i dont know FOR SURE if its really going lean (got no a/f monitor yet) but my friends TSI is doing the same thing, coughing real hard and pulling back at full boost, and when it starts doing it he spikes really lean.

ill pull the efi code in the morning and then check the codes again, im hoping its just my harness finally giving out (planned on buying a new one when i upgrade everything in springtime anyway) and that the sensors actually still work. even if some of them are bad i atleast hope the cps is ok cause thats one of the ones stinger doesnt replace D:
 

jdub

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Code 12 points at the CPS or it's wiring. The wires around the CPS connector frequently become brittle...you may have to re-wire it.

Code 24 & 31 are the AFM or it's wiring. Check the connector for a solid connection...it could be the wiring as well. FYI - both these codes put the ECU in fail-safe mode...standard values are substituted vs actual condition. That is likely why your motor behaves the way it does.
 

turbo87targa

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jdub;1167144 said:
Code 12 points at the CPS or it's wiring. The wires around the CPS connector frequently become brittle...you may have to re-wire it.

Code 24 & 31 are the AFM or it's wiring. Check the connector for a solid connection...it could be the wiring as well. FYI - both these codes put the ECU in fail-safe mode...standard values are substituted vs actual condition. That is likely why your motor behaves the way it does.

ah. Thank you jdub. Well I'll be buying a new harness here in 2 weeks and if that doesn't fix it I'll be buying a standalone ( and cps )
Kind of a set back buying it early but that's one less thing I'll need come spring time.
 

turbo87targa

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Nick M;1167476 said:
That is a rich condition. Accompanied by smoke. Lean will miss. I can't believe you dont' have a 34.

no smoke and no 34. After what jdub said it realy sounds lean, rich would have the smoke u mentioned and possibly smell gas?