93 LS 400 code 31,41 and 47
08-07-17, 08:42 PM
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93 LS 400 code 31,41 and 47
Hey guys I'm new here and i hope I can get some help.
i have an 93 ls400 getting code 31 Maf,41 tps and 47 sub tps, and at first start smog withe and smell like gas and missfire,after 10 minutes idling smog goes away but cars feels like in limb mode, some times check engine light doesn't light up when you put ignition, i check fuses and all are good. After I erase the codes removing EFI fuse , the codes come back after first test drive.. any suggest before I start changing some parts??
i have an 93 ls400 getting code 31 Maf,41 tps and 47 sub tps, and at first start smog withe and smell like gas and missfire,after 10 minutes idling smog goes away but cars feels like in limb mode, some times check engine light doesn't light up when you put ignition, i check fuses and all are good. After I erase the codes removing EFI fuse , the codes come back after first test drive.. any suggest before I start changing some parts??
08-09-17, 07:02 AM
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I'd check the ECU capacitors when unrelated multiple codes were read.
https://www.clublexus.com/forums/ls-...capacitor.html
https://www.clublexus.com/forums/ls-...capacitor.html
08-09-17, 07:38 AM
#3
I had white smoke on start up and revving, Mine would idle ok until it reached operating temp and then the idle would bounce down and back up. First things first. Change the AFM. It fixed the problem I mentioned form me. Also remove and clean your IDLE AIR CONTROL VALVE and Throttle body. Remove and reset the TPS. See how you go.
08-10-17, 01:48 PM
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1993 LS400 code 31 and 47
Update,,
I did check continuity from both tps and afm to ecm and wiring was good no broken wires,so I cleared the codes and check engine light is on right away after 5 seconds of engine running so I decide to try with different afm and and guess what?? That was my problem, no check engine light and engine running smooth again.
I did check continuity from both tps and afm to ecm and wiring was good no broken wires,so I cleared the codes and check engine light is on right away after 5 seconds of engine running so I decide to try with different afm and and guess what?? That was my problem, no check engine light and engine running smooth again.
08-10-17, 02:37 PM
#5
Update,,
I did check continuity from both tps and afm to ecm and wiring was good no broken wires,so I cleared the codes and check engine light is on right away after 5 seconds of engine running so I decide to try with different afm and and guess what?? That was my problem, no check engine light and engine running smooth again.
I did check continuity from both tps and afm to ecm and wiring was good no broken wires,so I cleared the codes and check engine light is on right away after 5 seconds of engine running so I decide to try with different afm and and guess what?? That was my problem, no check engine light and engine running smooth again.
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