i have a problem

[Pokey2301]

of course...its a mk3 supra, 90 turbo, auto to 5sp, :S

cars been down for 5 years, just got around to swapping the motor out, i finally got it to start, and now its idling funny, i could hear the isc valve through the intake, and that kept it from revving over 1000rpms, and i swapped that from my old motor, and it fixed it sort of. It would drive but wouldnt build boost and wouldnt rev over 2500 rpms and would idle great, no leaks, no overheating. I started it about 8 hours later and its repeating itself again, like the isc valve is open all the time, i pinched the hose for it and it idled smoothly, and i tried to rev it and it wont go over 1000 rpms again. and im getting a 31 code (afm signal)

its got a 3in ddp, lex afm, 550cc, greddy safcII, greddy profec b boost controller(not hooked up til its safe to run) and i kept the wiring harness from my old motor and spliced in the plugs for the 550cc injectors

any help would be appreciated!

Jeff

 

[I6Boost]

If its idling funny and wont build boost it sounds like a vacume leak..
&& I'm not sure but do all lex/550 give the code 31? If not check your AFM obviously.

Also open your hood and when you turn your key to on position you should hear your ISC click.
If not then replace it.

 

[Pokey2301]

ok, i swapped out the intake manifold from my old motor, so it has everything from my old motor except the block...and for an hour it was doing its normal thing, running like crap, wont rev, wont build boost, hesitating, so i let it idle for about 45 min while i aired up the tires, and i was playing with the safc and all of a sudden the check eng light went off and it ran perfect, i even drove it around and boosted it, stock boost only....and it ran perfect

i was gettin a 24 and 31, which is inlet air temp signal and afm signal

and i shut the car off and went to bed, and i tried 6 hours later and its doing the same thing again. it wont rev past 2000 rpms but im not getting any codes this time

the isc valve works, it clicks, and the afm worked great on the drive....its a weird bug!

also my battery wont hold a charge so everything the ecu did if it fixed itself it dumped it all

thanks

 

[Pokey2301]

well weird thing again, it runs great again, no leaks no overheating, it boost great, and all this after about 45 min of idling, my only guess is that the ecu is programming itself everytime cause the battery wont hold a charge cause it sat so long, so its like the ecu is starting all over again everytime i start it...and this time i didnt get any codes at all

ill know for sure once i get a new battery and see if it does it some more

 

[Pokey2301]

the car is still acting funny, code 31 still, ive used 2 afm also, and the car does the same thing all the time! im frustrated about it!

ive ran my car without the honeycomb on the afm for a couple years and no problem, would my car all of a sudden not work without that?

 

[ben1984j]

Code 31 also points to the entire AFM circuit, not just the AFM itself, so check into that. Seems likely to be a wiring problem if it continued after swapping the AFM, although it's possible both of them were bad (the TSRM tells you a way to test them)...

I doubt running without the honeycomb is the reason for your code 31 but the honeycomb is integral to the design of the AFM, your car won't run its best without it...

 

[Pokey2301]

its weird though, ever since i had that afm, ive never had the honeycomb in it, and i ran a 14.2 at 98 at sacramento with it, and i am going to check the wires and ecu

 

[Pokey2301]

well after just messing with the ecu and the wires to the afm, unplugging the safc and ecu a few times, it started working