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**doc_rock** · 05-04-2022

Originally Posted by ralmo94

Plugs wires rotor all on good shape? What does she AFR or O2 sensor do when it happens, what is the timing doing when it happens?
Have you tried reviewing a data log with the EKG type lines to look for a poor TPS signal, map signal ECT?
That's all "I" can think of. Sure someone else will chime in.

New cap, rotor, wires, and plugs. New TPS which has smoothed the trend line on its operation. New IAC since the old one was sticking open about 15 steps. Now (since this posting) I have developed an issue where it will only datalog for a short time then stop all communication with the serial module. I am guessing it is a grounding issue, but I can't seem to pinpoint that just yet.

**ralmo94** · 05-04-2022

Originally Posted by doc_rock

New cap, rotor, wires, and plugs. New TPS which has smoothed the trend line on its operation. New IAC since the old one was sticking open about 15 steps. Now (since this posting) I have developed an issue where it will only datalog for a short time then stop all communication with the serial module. I am guessing it is a grounding issue, but I can't seem to pinpoint that just yet.

Where are your sensor grounds? If they are on the thermostat housing, consider moving to the block or head.
That's all I got.

**doc_rock** · 05-05-2022

Originally Posted by ralmo94

Where are your sensor grounds? If they are on the thermostat housing, consider moving to the block or head.
That's all I got.

I've got grounds everywhere - the thermostat housing is a remote setup, so i tapped into that and ran a ground from that to the block. ECM grounds are at the back of the driver's side head where they were originally. body to block ground is back of the passenger side head, where it was originally - and another ground ran from body to battery.
The datalog is driving me nuts. I'm not sure if it's something with the serial to USB connector, the ECM, or the laptop. I can't reliably reproduce it, and there doesn't seem to be any method to it. Sometimes it logs for a few minutes, sometimes only for a few seconds. ALDL connectors all pin out with 5v, ground to ground connection is solid.

**ralmo94** · 05-06-2022

Originally Posted by doc_rock

I've got grounds everywhere - the thermostat housing is a remote setup, so i tapped into that and ran a ground from that to the block. ECM grounds are at the back of the driver's side head where they were originally. body to block ground is back of the passenger side head, where it was originally - and another ground ran from body to battery.
The datalog is driving me nuts. I'm not sure if it's something with the serial to USB connector, the ECM, or the laptop. I can't reliably reproduce it, and there doesn't seem to be any method to it. Sometimes it logs for a few minutes, sometimes only for a few seconds. ALDL connectors all pin out with 5v, ground to ground connection is solid.

Stupid question, not using an inverter are you?