400 SBC TBI tweak
#53
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Re: 400 SBC TBI tweak
RBob.
#55
Re: 400 SBC TBI tweak
Good info. Well, I still have something off. I can run the original al 24 pin chip (has the 400.bin on it). But when I go through the process of setting the chip type (512) erase successful, select bin, write, then verify- when I put that chip in the ecm it runs in I guess limp mode fast flashing service engine soon...crappy. what's odd is when I read the 28 pin chip it reads the same as when I read my original 24 pin (that has the 400.bin ) any thoughts?
Last edited by Mark Uptergrove; 04-09-2017 at 04:21 PM.
#61
Re: 400 SBC TBI tweak
Greetings again. I am at my wit's end. I have verified grounding, the purple wire back to the ecm, replaced the O2 sensor, and I still do not get any readings on the O2 while logging. DC voltage from the purple wire to the ecm is a constant 1.4V. could this be a ECM issue or is it possible that something is wrong in the programming disabling the O2? thanks guys
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Re: 400 SBC TBI tweak
Check the tan wire to ECM pin D6, it is the O2 input ground. Without it there won't be a valid reading.
> and I still do not get any readings on the O2 while logging
What voltage is the ALDL reporting? If the sensor it dead or unplugged it should report about 450 mV. That is the default setting.
RBob.
> and I still do not get any readings on the O2 while logging
What voltage is the ALDL reporting? If the sensor it dead or unplugged it should report about 450 mV. That is the default setting.
RBob.
#64
Re: 400 SBC TBI tweak
I am on o2 sensor #2, so hopefully it is the tan ground. I know the ecm is grounded, I'll trace the tan wire out. Crossing fingers this is driving me nuts.
#65
Re: 400 SBC TBI tweak
Check the tan wire to ECM pin D6, it is the O2 input ground. Without it there won't be a valid reading.
> and I still do not get any readings on the O2 while logging
What voltage is the ALDL reporting? If the sensor it dead or unplugged it should report about 450 mV. That is the default setting.
RBob.
> and I still do not get any readings on the O2 while logging
What voltage is the ALDL reporting? If the sensor it dead or unplugged it should report about 450 mV. That is the default setting.
RBob.
#66
Re: 400 SBC TBI tweak
Bingo..d6 is open...I cannot for the life of me find or trace out the end of this solid tan wire under the hood any places to check or...do I jus cut it and ground it?
#67
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Re: 400 SBC TBI tweak
RBob.
#69
Re: 400 SBC TBI tweak
Thanks for all the input guys. The tan wire went to never never land apparently so when I grounded it bam closed loop. I do have a question about putting a heated O2 back on. Will I be good grounding the 02 Sensor to the frame or do I have to run its ground to the D6 on the ECM? (which is now grounded and working with a single wire o2)
#70