Is there an odb1 cable that is USB that you recommend for running the APP from a laptop?

 

The Actron Scanner tool looks nice. If it's more useful than the app then I'm ok with getting one.

 

You have to read the linked thread. He tells you how to build or buy a cable.

I don’t use Scan9495 because I don’t run my engine with the stock PCM. I have an aftermarket engine management system that can easily be switched between running max performance with and without the huge shot of nitrous.


I find a data log that includes a code list to be much more useful than just a list of codes. Even if there are no codes, it’s possible to chase a problem by looking for cause and effect relationships between the sensors and other parameters. Using this approach I was able to show MSD why so many people using their Opti were experiencing highly erratic idle due to an issue with the MSD design. My MoTeC ECU is always logging the system operation. If a problem happens I can save the log and review it when I can connect my laptop.

 

Ok nice. I saw the link on his app and instructions on the pin. Gonna try and get this setup today.

 

The big problem with the data logs is there doesn't seem to be too many of us willing to take the time to help people out by reviewing them.

 

I won't have a cable delivered for a week or two. Then I'll be able to run logs and learn how to interpret the data. Would it be advisable to use a paperclip and jump A and B on the port and read what codes the SES light flashes until I can run full tests?

I'm doing a power steering flush, coolant flush, and interior n engine bay wipe down over the next couple days. (Making sure to protect the opti with a towel under the bleed screws)

Also going to take pictures of my aftermarket A/C components. Is it possible that I have a PCM code that's not allowing the relay to power the A/C clutch? I read that code 61 could do that. This is why I'm interested in pulling codes if possible before my 12 pin to usb diagnostic cable arrives.

 

1993 was the last year you could flash the codes on the SES light by shorting the diagnostic connector pins. Can’t do that 1994 and newer. You have to use an OBD-1 scanner.

As noted earlier, for vehicles that left the factory with A/C, low refrigerant pressure sets a code in the PCM, and that in turn prevents the compressor clutch from being turned on. There are other codes related to the A/C as well. But I would think that the PCM program for a 1LE without A/C would not have the diagnostics for those codes activated.

If someone simply bought all the factory A/C components, and connected the unused 1LE harness connectors to wire them, I would think they would have had to reflash the PCM. But all this is an assumption on my part. The 1LE's, without A/C in the early model years, are not something you run across every day.

Reading a data log can be intimidating. Typical scan rate can be as high as 8 frames per second (higher scan rate is better), each frame is a line of data extending across 52 columns of sensor readings and PCM parameters. At 8 frames per second, that’s 480 lines of data per minute x 52 columns = a shade under 25,000 pieces of data. A good data log begins with a cold start, with the PCM in open loop. Typically, it takes the PCM 206-seconds to enter closed loop. Then you drive it for a few minutes at varying conditions that replicate the conditions where you have experienced the problem(s) in the past. That's at least 10 minutes total, so you have 4,800 lines of data, with about 1/4-million pieces of data.

 

That's pretty detailed and lots to scrub. I'm sure once familiar with the logs you're able to review pertinent columns and identify trends and root cause analysis. I'd be happy to just have an initial baseline scan to work with.

I'll be waiting a bit until I can pull codes, but have plenty to keep me busy.

 

Here's some photos of the engine bay, both fuse boxes, AC components, and HVAC control panel.

Engine Bay Photos

 

Looks like they used a stock compressor in the stock location. But the wiring and line routing looks totally non-stock. The absence of a compressor relay in the stock location in the under hood box would seem to indicate they did not integrate the controls with the factory setup. I really can’t review in detail and compare to stock, because my A/C was deleted almost 20 years ago. When you get Scan9495 running, we can look and see if the stock refrigerant pressure sensor and evaporator coil temperature sensors are connected to the PCM.

 

I hope it's integrated 😄

 

Hi Fred,

I got the 12pin to USB cable in, and installed the scan9495 application and have it ready to go. I read the installation and user guide ready to try my first scan this evening. Are there any preliminary setup tips for recording specific data that you recommend prior to recording?

-Eric

 

The standard report contains 52 columns of data. They always look the same. If some things seem superfluous, I just hide the columns so I can focus on what seems more important. I actually don't use Scan9495. I replaced the factory PCM in 2000 with an aftermarket engine management system, more suitable to running an engine with a huge shot of nitrous. If you need more info on the specifics of the setup, I can ask GaryDoug to look at your questions.

To make things useful, do a cold start, let it warm up about 4 minutes without doing anything, no revving the engine, etc.. That should put the PCM into closed loop. At the end of this period, turn the A/C on for a minute. Then turn it off. Then just drive the car for 5 minutes or so, varying throttle and RPM. Again, while driving, turn the A/C on for a minute. That’s probably more than I need to determine if the A/C has been integrated into the PCM. But, since your running the log, I can look it over to judge the general condition of the way the engine is running.

 

Ok will do, thank you.

 

Hi Fred,

I hope I did this correctly. After getting my laptop to recognize the port, I turned the ignition switch on and then plugged in the 12pin cable, waited a bit and started the vehicle. I let it run without touching it for several minutes and then cycled the A/C control to max, A/C, and the rest of the HVAC control panel settings. Turned it off and went for a winding drive around the neighborhood at various RPM. I then stopped recording, and this is the file it generated that's attached.

Thanks,
Eric