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There seems to be different mystery faults appearing at random? Red brake light is pressure, fluid level etc.. Amber light is for ABS and will set codes accessed from the ALDL. Quad drivers is a sort of catch all. It seems the scanner is being specific, but there are several drivers in a basket in the onboard system. Injectors, cannister purge, EGR, TCC and maybe others are in the quad driver category. Did the UART notice show up again? If that communication gremlin is moving around it may be a devil to focus on something.

I never topped it off... and its the only fluid I never changed... but, it looks clean and smells fine. I checked the vac line and it was clean too. I simply made sure there was fluid on the stick to test drive... and forgot to officially check it for fullness till today. I'll make the updated video over the weekend. I went to get my JVC head and universal antenna all wired in and working. Alpines up front, 3way kickers in the rear. Sounds 10x better now. However, as I pulled out of the shop, my red break light is on again... so need to pull codes for that. I'll have to pull codes for that now as my reader won't display them... only tells you what they are... as they come in using the blink method. As the car was at temp, I did run through a few. In the body, there is a quad2 fault. I checked GM reasons and one was the emissions purge valve... just received that part today. Engine was running in open circuit too. I'll make a video with all of this stuff though. Need a break today.

Were you able to check this from Tuesday?

2seater, looks like we are on the same page. 🙂

It could be related to your misfire. Trans fluid can be sucked into the engine through the modulator valve vacuum hose. Pull the hose off the modulator and see if it had trans fluid in it.

Also, providing the proper method of checking trans fluid is running in park, it shows a quart low. Im gonna remedy the situation but don't feel it will change the immediate issue. Unless the engine is drinking the fluid?

It dosnt ever stall out. It has a slight idle drop and vibration intermittently at a stop. When driving either streets or freeway, I really don't experience any adverse effects. Im going to try to upload a new video today demonstrating this with the reader plugged in and operating at temp.

I don't believe there is any more that can be done for the peculiar information that comes up when viewing ECM data, as well as a single item in BCM data. The new Prom made no difference in the way data is displayed. The data does display the correct code for the ANCX Prom, so at least that worked. After a careful examination of the ECM and BCM data it was determined the data is in fact correct and displayed in the correct order but 2/3 of the labels or descriptions are incorrect. Essentially, if this was a 90 or 91 with only the data identifier number and the data itself, this wouldn't be a question. This case is closed for now. My son is pursuing the possibility of a slow leak in the a/c system but the system held vacuum overnight and using the R12 we had on hand at the time, which is a few oz. undercharged, the system is working for now.

I watched the running video a couple more times and the engine definitely needs rpm to get the fueling adjustments via the O2 started. Once it was heated up, it continued to remain active even when it dropped back to the idle range. The UART issue is something in the serial communication. Hard to be specific but it seems to go hand in hand with the weird previous behavior. Did I understand that the engine quit at a stop when driving?

Ok, I found a photocell. Not only does it work, it also cured the B119 error. BD44 shows values between 10 and 90. ...but still no background illumination. I'm starting to run out of ideas. The inverters?? Power supply module?? BCM?? Any suggestions? HAHA! My bad. Forgot to reconnect that 2A12-wire. Without that there is no power to the luminescent foil and the inverters. Gotta try that next.

Nice videos! I wondered the same as others when I watched the O2 in the rich zone, (above 450mv),and the fuel integrator locked at 128. That must have been at idle, and it is not unusual for the O2 to cool off and stop doing its job. When revved up a bit it started to go rich/lean and the integrator floated around 128. It will always read 128 unless in closed loop. That is pretty normal. Idle conditions, especially extended idling, will go rich. I am not certain why that is but it is one way to keep the catalyst in the converter hot. Your numbers, fuel pressure and engine sound are pretty good. Nothing jumps out to me. Even the FSM will tell you that the engine speed must be raised for a period of time to get everything online, even if the engine coolant is hot. Today, faster computers, heated O2 sensors and O2's before and after the cat are normal. Not so 30+ years ago.

Is there a listing of what these readings should be? A place that I could try and learn from what is going on with the diagnostics? I just got a TECH 1A with several modules. I spent the day trying to learn how to use the instrument and what it is telling me. My short term memory caused me many problems. I see something, then try to go back to it and can't find it again. However, I am blessed with being an OLD may, into his four score years.

Thanks. i missed that.

I just ran through it again. at 3:17 it is closed loop and it is lean.

I think that would be a good idea. When in open loop the ECM is operating on data tables stored in memory. When it goes into closed loop the ECM starts looking at the O2 sensor and probably other sensors as well to determine the proper fuel mixture. The readings you show in your video aren't the true readings you will see when the engine is in closed. loop. The ECM should be operating in closed loop by 170* under normal conditions. If not there is a problem keeping that from happening. See if you can get it to go into closed loop and post another video of your readings. By the way, you did a good job on the video. Very helpful. that looks like a really good scanner.

No... I checked it a couple days ago and it was closed. It would have been run a bit longer too that day. Not sure of the temp at the time as all these readings are a bit new to me... or what normal looks like even. I could run it to full operating temp and make a new video if that helps. Are you suggesting the temp sensor may be faulty? It is still the one that came with the car.

This is what I saw at the front of the video. Was the video recorded in parts at different times?

It was showing closed loop the first time I checked.

I've not made it all the way through the video yet but the first thing that stands out to me is the coolant temp is 200 degrees and the scanner says the engine is still operating in open loop. At 200* it should be in closed loop. Does the scanner ever show that it goes into closed loop?

The exhaust output reading fluctuates rich/lean if thats what tou are asking. I think towards the end of the video it shows this. It is a new sensor also.

Did your O2 Sensor ever switch to LEAN? Have you done any checking of it? Jim

I posted to YouTube 2 videos. Fuel preassure test and diagnostics. Im not sure what to make of the B411 and E47h codes. Fuel preassure readings... Diagnostic readings...

175 psi, huh? Thanks for the info., I'll report my finding when I have them but I'd hste to do the cylinders next to the firewall, damn hard to get at them!

I bought a used engine from a salvage yard and their testing was all the cylinders were in the 175 range. I am in the belief that to be about where you want to be.

Someone else may need to answer the specific question if you are looking for actual numbers. Only from memory because my build sheets only include the physical specs of the mechanical assembly of the engine. My three engines are all different compression ratios, so I cannot even venture a guess. I do believe my 9.5:1 one tested at ~205psi, but this is definitely not a stock engine. Too high is not always a good thing either. It may be caused by lots of carbon buildup. Consistency is most important.