my car started idling like crap and dying, so i unplugged my afm and it idles fine. does that means its bad? would this have anything to do with me not boosting 7psi with an intake and 2.5 in exaust?
is afm bad?
- Thread starter 87supraturbo19
- Start date
I have codes
42 Vehicle Speed Sensor Signal. which i plugged in today
31 Air Flow Meter Signal
24 Intake air Temp Sensor Signal
42 Vehicle Speed Sensor Signal. which i plugged in today
31 Air Flow Meter Signal
24 Intake air Temp Sensor Signal
2 air flow meter codes could very well be from a bad connection. You can have an intermitent signal, or not have the 5 volt refrence. Check the plug for bent pins and make sure the wiring looks good.
You'll need a voltmeter.
Here's the troubleshooting flow chart for Code 31:
http://www.cygnusx1.net/supra/library/TSRM/fi/FI_038.html
For code 24:
http://www.cygnusx1.net/supra/library/TSRM/fi/FI_040.html
http://www.cygnusx1.net/supra/library/TSRM/fi/FI_060.html
Hopefully it's not the AFM electronics...very expensive piece. Like Nick said, could very well be the connection to the AFM. Do the tests above and that will tell you.
Here's the troubleshooting flow chart for Code 31:
http://www.cygnusx1.net/supra/library/TSRM/fi/FI_038.html
For code 24:
http://www.cygnusx1.net/supra/library/TSRM/fi/FI_040.html
http://www.cygnusx1.net/supra/library/TSRM/fi/FI_060.html
Hopefully it's not the AFM electronics...very expensive piece. Like Nick said, could very well be the connection to the AFM. Do the tests above and that will tell you.
87supraturbo19 said:
So AFM resistance is good.
Did you do the tests I posted above?
Note the tests are done at the ECU and the flow charts will refer you to additional tests.
87supraturbo19 said:
Ok...pull the EFI fuse in the box under the hood to clear the codes. Wait one minute and plug the fuse back in. Drive the car and recheck for codes. It might have just been a bad connection at the AFM.
ya i already did and no codes. thanks for the help. now if i could just figure out why its missing at high rpms.
87supraturbo19 said:
glad to see 1 of your problems are fixed....
its always fix one thing next another prob....
what rpm do u be shifting at???
actually what mods on ur car???
87supraturbo19 said:
You mentioned 7 psi of boost...I assume this is this a stock turbo. Do you have the wastegate shimmed for more boost?
A high rpm miss can be a couple of things...the most simple are the plugs/plug wires. Stock gap on the plugs (for a turbo) is.031"...for higher boost, gap at .028". If you haven't replaced your plug wires in a while, could be time.
ok lets say i have it floored in second at about 5500 rpms it starts to miss just ever so lightly but i can feel it. i have a new clutch. new fuel pump and filter. i did have the stock turbo shimmed because i couldnt get it to boost pass 4 to 5 psi. i have an intake and 2.5in exaust. even with the 4mm shims i could only hit 7 psi on a 70 degree day. its probably the plugs and wires.
87supraturbo19 said:
You could also have a boost leak. Check the piping from the turbo to the intercooler to the throttle body for cracks or holes. Check the clamps too.
ya i have double checked all my pipes.they all look good. but there is one spot i suspect might be the culprit.
87supraturbo19 said:
Sometimes the cracks in the rubber piping is hard to see...you might have to flex it (with a bright light) to see a crack. With your wastegate shimmed, you should be getting more boost than 7 psi.