I used the search tool and learned mostly that LG4 questions go unanswered on this board but I will give this a shot.

I would like to hook my laptop up to my ECM and I know I would need a few things to do this:

1. My laptop. Windows XP is on it so I'm ok there.

2. I would need to make or buy a cable to run from the ECM into the laptop's USB.

3. WinALDL. Free to download.

My questions are as follows:

Is my stock Q-jet 160 baud (the requirement for WinALDL)?

Is it worth the time and effort to do this? I'm interested in studying my motor, even though the computer only controls a few things on the carb and TC lockup. The main area I wanted to study and test was my air-fuel ratios, specifically to test carb rods and hangers and different air intakes, but I didn't see any air or fuel read-outs on the ALDL. I only saw one or two screen shots of the software so I could have missed it. Thanks for the time.

~Matt

 

My attempts with WinALDL were unsuccessful on either an 85 or 87 LG4. I have since bought a scanner and it works well. You may have better luck though. A search when I was trying turned up as many reporting failure as success.

I assume you're interested in AF ratios for the secondaries. The ECM will only provide you with O2 sensor readings and a rich/lean flag. Don't know if WinALDL will use the data to convert to an AF? Keep in mind though that it's a narrow band sensor.

 

If ALDL won't do it then what could give me real-time A/F data from the car?

~Matt

 

A wide band O2 Setup is the most accurate way to get real time A/F ratio data.

 

Exactly

 

Any recommendations?

 

I looked into some of the wideband O2 sensors, thanks guys.

Naf:

Which scanner worked well with the LG4 for you? Why did ALDL not work for you? Was it the ECM that gave you problems or software trouble?

~Matt

 

I use an Autoxray 6000. Never figured WinALDL out. Tried every cable configuration out there and two different laptops. It could, however, have just been me.

 

The LG4 ECM is 160 baud so WinALDL will work. I've used an older MPSI 9000 scanner on them successfully.

Now for the bad news: you can't scan the ECM while the engine is running without changing how the ECM runs the engine. So it isn't worth the effort of doing this.

To get the ECM to send data the ECM needs to be put into diagnostic mode. This changes several internal parameters including adding timing. It becomes a mess trying to drive the car as it pings most of the time. Everything changes.

For AFR data, as others have mentioned, best bet is to get a standalone data logging WB system. Many can data log while driving then dump to a laptop. Can usually input the TPS, MAP and RPM at the same time.

Note that the ECM doesn't control WOT in the carb. So it is mechanical changes, rods & hangers, for tuning.

RBob.

 

WinADL has very limited support of ECMs. It wouldn't work on my carbed LG4 car or my friend's 1987 LB8 car. Looking at the documentation for it the program basically supports only certain ECMs in TPI cars ranging from 1987 to 1989. I don't even believe speed density was supported. I'm not sure on that since that was a few months ago that I was playing with it.

 

WinALDL supports a lot of different ECMs and vehicles. Can see the list here:

http://winaldl.joby.se/aldldata.htm

LG4 is the last one on the list.

Most likely the reason it won't work on some vehicles/ECMs is the cable itself. Very few do a proper conversion from the inverted 5 V signal to true RS-232 signal levels. And if you forget the 10K resistor then the ECM won't send any data to log.

RBob.

 

Thanks guys for your help. I looked into the Autoxray and it looks like a good product, just expensive. I'm assuming this scanner won't need the car to be off like the WinALDL?

I'm looking for a way to hook up my computer to the car and get accurate and live data. It doesn't sound like this is possible unless I just use a scan tool or I get a wideband O2 and a gauge for my AFR readout only. Is that correct?

~Matt

 

WinALDL is a scan tool, but can also data log. Most hand held scan tools can't log to a laptop. DataMaster can as it is a Windows based scan/data-logging tool.

It doesn't matter what is connected to the ALDL plug in the car. The ECM won't spit out data unless it is in diagnostic mode.

RBob.

{edit: changed "Most hand held scan tools can log to a laptop. " to "Most hand held scan tools can't log to a laptop. "

 

Ok I got it. Thanks RBob.

~Matt

 

The scanner does disable knock retard when connected. It is, however, still a valuable diagnostic tool-as long as you're not trying to figure out what's wrong with your spark curve...

Older LG4s that don't have a KS will show spark-timing information on the scan tool. Figure the ECMs ran out of space when the KS feature was added.