350 TBI high idle

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gmbellew

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Where do you think I’d find that in WinALDL?

Here’s a shot while it’s idling high in park:
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There are obviously many more screens and I did datalog the whole thing.
check the flag data? I use adldroid, so am not familiar with winaldl.
 

Frankenchevy

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check the flag data? I use adldroid, so am not familiar with winaldl.
This is what is on the flag data tab:
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Do these values look correct?
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Another thought…it’s only ever done this while hooked up to the Moates cable. There’s no way for the configuration of this cable or winaldl to mess with the ECM, correct?
 

gmbellew

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So if you unplug the cable, it doesn’t do it?

I have never noticed anything different with my Bluetooth cable connected to my ALDL.

Maybe your cable is a little different and has something that is forcing it into a diagnostic mode or something?

Check the baud rate. I thought tbi was very slow at 160.
 

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So if you unplug the cable, it doesn’t do it?

I have never noticed anything different with my Bluetooth cable connected to my ALDL.

Maybe your cable is a little different and has something that is forcing it into a diagnostic mode or something?

Check the baud rate. I thought tbi was very slow at 160.
I have to check, it's only been driven with the cable attached for the last few days.
 

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Having the cable attached cannot write any changes to the ECU or PROM, you would have to have an actual PROM burner and a lot more expensive stuff (and even then you can't change an existing PROM, only write data to a new one and swap it in). So there is no danger to having the cable connected. One thing that CAN change operation is having the 10K resistor enabled between pins A and B - that will make the computer run in a slightly different mode. On mine if I had the 10K resistor enabled it wanted to idle at 1000RPM, with the 10K off it will idle using the programmed 750 value.
 

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Having the cable attached cannot write any changes to the ECU or PROM, you would have to have an actual PROM burner and a lot more expensive stuff (and even then you can't change an existing PROM, only write data to a new one and swap it in). So there is no danger to having the cable connected. One thing that CAN change operation is having the 10K resistor enabled between pins A and B - that will make the computer run in a slightly different mode. On mine if I had the 10K resistor enabled it wanted to idle at 1000RPM, with the 10K off it will idle using the programmed 750 value.
So...don't leave the "paper clip OBD1 reader" in the OBD1 ports when not necessary?
 

gmbellew

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So...don't leave the "paper clip OBD1 reader" in the OBD1 ports when not necessary?
It doesn’t matter. I have mine always plugged in to aldl. I plug it in to power when I want to use it. Added a plug by the aldl port so I can just plug it all the way in quickly while I am driving.
 

YakkoWarner

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So...don't leave the "paper clip OBD1 reader" in the OBD1 ports when not necessary?
I'm not sure what happens if you run the engine or drive with the paperclip jumper between the A-B pins. I mistakenly started the engine once like that and the SES light started blinking really fast like a strobe light, so I immediately turned off the key and corrected my mistake.

A paperclip jumper is a zero resistance short between the 2 pins, which tells the computer to start blinking out the codes on the SES light.
Having those pins jumpered is not necessary to read the ALDL data stream. The data stream is a 1 way series of pulses that comes off a different pin and is always "on", regardless if anything is connected to that pin to listen to it.

Some data logging cables have an optional 10K resistor (usually selectable with a switch) between those pins which tells the computer to go into a slightly different operating mode.
 

gmbellew

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I'm not sure what happens if you run the engine or drive with the paperclip jumper between the A-B pins. I mistakenly started the engine once like that and the SES light started blinking really fast like a strobe light, so I immediately turned off the key and corrected my mistake.

A paperclip jumper is a zero resistance short between the 2 pins, which tells the computer to start blinking out the codes on the SES light.
Having those pins jumpered is not necessary to read the ALDL data stream. The data stream is a 1 way series of pulses that comes off a different pin and is always "on", regardless if anything is connected to that pin to listen to it.

Some data logging cables have an optional 10K resistor (usually selectable with a switch) between those pins which tells the computer to go into a slightly different operating mode.
For some reason I was thinking that if you run with it jumpered, the frequency of flashes has to do with open vs closed loop. But I might be remembering that wrong.
 
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