Help! Can't get ALDL data

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Jan 27, 2018 | 12:31 AM

rrubel

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Burning Brakes

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From: Glen Burnie MD

Help! Can't get ALDL data

So I finally found a place to take my '86 to get its MEMCAL tuned, and the guy there can't get any runtime data from the computer. He's tried the normal ALDL plug and software on a laptop, and also a Moates APU1. The Moates is being used for seat-of-the-pants A/F tuning with a wideband O2 sensor but to get all the spark settings right he really needs the full data log.

He said he gets mostly gibberish, nothing that any of his software packages can decode. He runs a Vette performance shop and seems to know what he's doing, but my car is stumping him.

Anyone got any thoughts?

Thanks!
[RICHR]

Jan 28, 2018 | 04:02 AM

WVZR-1

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The '86 - '89 TPI with the 165 ECM required a 10K resistor A-B. Is it the issue? No idea. There should be many GOOGLE reads. here's just 1 very old one that got referenced a lot 'back in the day'.

http://www.aldlcable.com

Jan 28, 2018 | 02:09 PM

tequilaboy

Melting Slicks

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From: Lakeville MI

86 is a special case. The $32 serial data initialization code is a little bit different than 87-88, and 89 bins. This makes it difficult or impossible to log at 8192 baud with standard methods.

Diacom users have reported success logging at 8192 baud. Since Diacom had its own cable and adaptors, it is possible that it was able to connect in diagnostic mode with pins A and B shorted. This is speculation on my part and has not been confirmed.

If you have an auto trans car, an easy work around is to use a newer $32B or $6E bin. Spark advance table may need to be tailored for the 86 iron or 128 heads, if using a newer bin.

I've also rewritten a few $32 bins to correct the serial data initialization, so this is another option, especially suited to 86 4+3 cars. Due to the 86-only differences in the on/off switch wiring, lack of 1st gear switch, and 1st gear detection logic, the later bins won't drop-in and provide correct 4+3 function without modification or re-pinning.

I've uploaded a test bin here: (see post 34)

https://www.corvetteforum.com/forums...post1595584637

My test bin should connect at 8192 baud with 10 k resistor and an appropriate polling message provided by the adx/scan tool.

Last edited by tequilaboy; Jan 31, 2018 at 06:02 PM.

Jan 28, 2018 | 03:08 PM

JrRifleCoach

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From: Freedom is never more than one generation away from extinction.

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Jan 30, 2018 | 06:20 AM

rrubel

Thread Starter

Burning Brakes

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From: Glen Burnie MD

Quote:

Originally Posted by WVZR-1

Good thought, but that wasn't the issue. The APU-1 lets you connect to the ALDL either with or without the 10k resistor, and he tried both. It also lets you connect directly to the ECU (via piggyback) and that didn't get any valid data either.

[RICHR]

Jan 30, 2018 | 04:17 PM

rrubel

Thread Starter

Burning Brakes

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From: Glen Burnie MD

Quote:

Originally Posted by tequilaboy

86 is a special case. The $32 serial data initialization code is a little bit different than 87-88, and 89 bins. This makes it difficult or impossible to log an 8192 baud with standard methods.

My test bin should connect at 8192 baud with 10 k resistor and an appropriate polling message provided by the adx/scan tool.

Hmm. Ok, I'll have him give this a try. I know in the past I've gotten data out successfully but not for some time and there's been a number of electrical fixes/changes done since.

EDIT: So these bytes get inserted into the assembly at what address?

I wonder... I used to have an aftermarket Superchips MEMCAL (it was in the car when I bought it) but it (and the original ECU) fried due to wire shrinkage and shorting. I wonder if that chip was corrected from the manufacturer... because it's only been since replacing both that I have been unable to connect properly.

Thanks
[RICHR]

Last edited by rrubel; Jan 30, 2018 at 04:23 PM.

Jan 30, 2018 | 04:37 PM

tequilaboy

Melting Slicks

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From: Lakeville MI

It should connect easily at 160 baud, but this is of little use.

Its not as simple as inserting a couple bytes. How about some info on the car?

Auto or 4+3? Iron or aluminum heads?

What bin are you currently using? Check the broadcast code on the eprom label.

Jan 30, 2018 | 05:37 PM

rrubel

Thread Starter

Burning Brakes

Joined: Jan 2002

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From: Glen Burnie MD

Quote:

Originally Posted by tequilaboy

The car specs are in my signature. It's highly customized, hence the need for this tuner work.

I'm not sure what bin is currently in the car; I've had several mail order tunes and a stock bin burned to an EEPROM at various times (I used to have a Prominator with 4 of the 8 slots occupied, until that died as well). The guy doing the actual work MAY have started from one of the mail order ones, or he may have started from the stock bin. I'll have to ask him tomorrow.

Thanks.
[RICHR]

-= 86 Coupe 4+3 w/ 91 roller block, LPE 74219 cam, ported SuperRam and base, TRACO headers, PowerEffects catback, DUI distributor/coil, Pro-Topline ported heads (2.02/1.60), forged pistons, Flo-Kooler water pump, RD-Racing CrossBar and harness set, 96 wheels, more. Still being dialed in. =-

Last edited by rrubel; Jan 30, 2018 at 05:38 PM.