ecm in limp home mode& code23 help please!!
10-26-2001, 05:38 PM
#1
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Location: Middle TN USA
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Car: 89 FORMULA 350 / 1991 RX7
Engine: 5.7 L98 / LT1
Transmission: 700R4 / 6 speed manual
Axle/Gears: 3.42 posi / 4.11 posi
ecm in limp home mode& code23 help please!!
Ok today i checked my 89 gta 5.7 on a scantool and the outcome was this. code 23, is MAT/ -40DEGF.the tool also said that the ecm is in LHM. would this cause the ecm to be in limp home mode or do i have a bad ecm?any help would be great! thanks in advance
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89 gta 5.7 to many mods to list 89 formula 5.0 tbi (commuter)
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89 gta 5.7 to many mods to list 89 formula 5.0 tbi (commuter)
10-26-2001, 10:46 PM
#2
GTA,
That means the MAT/IAT has either failed or is disconnected. It is located on the underside of the intake plenum. The sensor is about ten bucks. Before you get all wrench-happy to replace the MAT sensor, read this article:
MAT/IAT Sensor.pdf
You'll need Adobe Acrobat Reader to open/view/print the file (see below).
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Later,
Vader
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If you want to beat the World, it might reach up and pull you down...
Adobe Acrobat Reader
That means the MAT/IAT has either failed or is disconnected. It is located on the underside of the intake plenum. The sensor is about ten bucks. Before you get all wrench-happy to replace the MAT sensor, read this article:
MAT/IAT Sensor.pdf
You'll need Adobe Acrobat Reader to open/view/print the file (see below).
------------------
Later,
Vader
------------------
If you want to beat the World, it might reach up and pull you down...
Adobe Acrobat Reader
Last edited by Vader; 03-31-2018 at 09:51 PM. Reason: Updated links
10-28-2001, 10:29 AM
#3
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Car: 89 FORMULA 350 / 1991 RX7
Engine: 5.7 L98 / LT1
Transmission: 700R4 / 6 speed manual
Axle/Gears: 3.42 posi / 4.11 posi
vader, i replaced the MAT sensor yesterday. and i'm still getting a code 23 . i have a 52 mm holley tb and a ported plenum the same size. do you think thats causing the code. and if so do i need to move the MAT sensor?thanks for repling 
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89 gta 5.7 to many mods to list 89 formula 5.0 tbi (commuter)
------------------
89 gta 5.7 to many mods to list 89 formula 5.0 tbi (commuter)
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