Take lots of notes helps too.

That is really odd all four corners have leaks. Oil through the head is merely a static drain back into the motor. Water on the other hand is pressurized. Doesn’t appear to be water though. Is it...

Might take notice of the O2 voltage readings.

EST module replaced?

This manufacture has a thumb drive with there cables. I was in the same boat, no cd drive. It’s where I got mine.
https://obd2allinone.com/products/aldlobd1u.asp

19827 not sure if the pic went through, but yes, coming off the coil there is a white wire with a connector which was/is used for diagnostic tach purposes by gm techs. I used it when I changed my...

A and B should have open loop between them, Yes?

Roger that. Possibly this will help. It’s pretty in depth.
http://www.gearhead-efi.com/Fuel-Injection/attachment.php?attachmentid=16091&d=1600473163

Holy mackerel! I would have never thought to mode the rotor cap! I just reclocked the distributor. Silly me. Yes we have all done it. Hopefully you only make that mistake once.

Possibly this thread will help. See post #5
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?11115-7427-ECU-OD-Lock-INT-BLM-to-128-vs-open-loop-for-VE-tuning

Yep, that’s the fuse to the fuel pump. Definitely need that. Looks just like the one on my 88 C1500.

It’s a long shot but, Might try a previous version of Tunerpro.

Welcome sir

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?173-1227747-to-16197427-Conversion-PCM-Swap-with-Wiring-Pinout-Directions!

A faulty temp sensor that goes to the ecm can play havoc on idle rpm’s.

Fair enough Mo, I was just sharing my experience, thought it might be helpful. Shed some light at a different angle. No disrespect intended.

Ok, with all due respect, I beg to differ with you. 99% of the mechs that deal with TBI understand that at some point you have to set/adjust the manual setting. Especially if it has been rebuilt....

Suggests the manual throttle setting may not be set right. Maronielb have you done the manual throttle set procedure?

Possibly a ground, but I keep thinking back about an issue on my C1500 where a wire in one of the connectors at the ecm had worked itself loose and became intermittent. The truck ran terrible. This...

The air cleaner assembly has actually come down even more now. The filter element is actually standard for my C1500

That is definitely something I’m going to look into, as I’m running a 14” open filter. I had always wondered about heat sink and what kind of affect it would have my 88 C1500

Nothing like keeping the factory look.

Yes sir I believe they will. That is really a nice setup.

Awesome Fast. Everything looks spot on.

Maybe this will be helpful don. The same principles apply. Backs up what daveW posted....