I just purchased this car and cannot get it run only idles if that. Will not rev past 1k and when let off it dies? I checked for codes and found 31. I have went through checked the ecu wires, all test good from what i have read (powers and grounds) checked connector at afm, have ground on E and E2, 4.9-5 volts on THA VC and KS. What am i over lookin? I did notice previous owner has cut and or spliced new wires from ecu to engine bay on E2, KNK2 and THG, have not determined if it was for an aftermarket controller or where the lead yet. Any and all help will be much appreciated thanks
in need of help code 31
- Thread starter 89supra7mgte
- Start date
The car does still acts the same, which is makin me believe it is the afm. Is there any other sure fire ways to confirm? i dont have any extras laying around nor am i able to locate any used ones at this time. One thing i have not done is test the resistance which i will do later tonight or in the am. Any idea of what or why he would have wired or rewired the ecu?
people spray carb cleaner in them in an attempt to clean.
you can do a resistance test, but i've seen them pass the test and still be bad.
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=96
just so you know, all you have to replace is the black box (kv sensor). the one from the v8 lexus (ls400/sc400) is the same. search some junkyards and see if anything comes up.
you can do a resistance test, but i've seen them pass the test and still be bad.
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=96
just so you know, all you have to replace is the black box (kv sensor). the one from the v8 lexus (ls400/sc400) is the same. search some junkyards and see if anything comes up.
Ok ill search for them as well it will be compatible with my ecu without any other mods? Any ideas why the po had spliced into the knock sensor egr temp and sensor ground (E2: afm, tps, coolant temp)
So i figured it out, regardless of the afm being bad and still throwing a code, my exhaust was completely plugged after the turbo. Pulled the o2 out and there she went started running smooth idling good and revving up. According to the guy i bought it from he said there was a blown head gasket i psi tested the system and thus far no psi loss. hopeful for smooth sailing now
What was it plugged with?
And what part of the afm sensor mechanics stops functioning correctly when cleaned improperly?
And what part of the afm sensor mechanics stops functioning correctly when cleaned improperly?
I think the car was running really rich at one time or another, it has a new jdm engine that has never been run due to the fact the guy thought he had a bhg and a blown turbo prior. Anyways the stocker had 200k. when i removed the down pipe the second cat was full of soot just a lot of black powder, like carbon but really soft. I am guessing that his blown turbo and too much fuel was the cause. I hollowed them out for the time being(until new system arrives) and it is running fine but still have afm code. tested resistance on afm and seems to check out ok. checked vacuum leaks and none found on tubes or pipes.
check the HZ of the ks signal with the car running. warm idle =15-25hz and should increase smoothly with rpms.
dbsupra90;1413340 said:
lewis15498;1416593 said:
The Karman Vortex AFM uses a very small foil mirror to reflect light from a diode. Use any type of Carb, MAF, etc cleaner and the mirror will haze. It's a sure fire way to FUBAR the electronics.
jdub;1416659 said:
So MAF cleaner is a nono. Guy at local parts store (small business owner, not an autozone nimrod) said that that MAF cleaner was the was safe for use on MAF, but unsure on AFM. I dont know how different the MAF cleaner was from carb cleaner, but he was a fan. It was a CRC product IIRC.
That said, is there any way you can clean the AFM?
jdub;1416949 said:With freon
Really? That I never would have guessed. I learn something every day!
Ok back on topic about code 31. I recently replaced with a 1jz non turbo afm (free) pretty sure its not correct due to code came back. can vacuum leaks that i have not noticed or found cause this? I have also realized that right after wot let off the car tends to die?are they related or am do i have another problem? any all info will be greatly appreciated thanks guys.
89supra7mgte;1417024 said:
- A 1JZ non-turbo AFM will not work...the Turbo ECU looks for a frequency (hz). Test per above.
- Vac leaks will not cause a code 31...a boost leak will make the symptoms worse though.
- If the car dies like that, it is likely related to this problem.
Why don't you test the AFM like Grim suggested vs using parts that were not made to work with this motor? Geez....
stop wasting time and test the stupid afm output. measure hz from the ks to e1 circuit at the afm connector. Shave back a bit of wire on each and presto... look in the tsrm for pin out.
i sense this conversation going south...
i sense this conversation going south...
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The afm (correct one now) tests out good. the car idles fine here and there tap throttle and dies and sets the code. its really annoying i wanna get it on the road before the snow. But this setup is having me run in circles. I am mechanically inclined but this is a new system to me.