I have the following diagram for an ALDL cable here and im wondering if it will work with my 1994 Corvette. Have any of you got this cable and can verify that it works perfectly with TunerCat as well as DataMaster?? I am going to be reprograming the ECM for a rear ratio change.... Thanks in advance

 

No one knows?

 

No idea, I'm running Craig Moates cables and using TunerPro RT, you might want to email Craig and ask him. Or maye Ray Mansur-think that's the man at tunerpro. If I had the knowledge to build all that stuff-I would've-but I don't.

 

Thanks mate.

 

A search will reveal many threads with schematics. Here is a recent one:

http://forums.corvetteforum.com/show....php?t=1358811

 

Thanks mate, ill check that one out

 

I have built this circuit for my 94 and it does work. Out of the 7 programs I have downloaded only 2 will work. This is because most I have found that most of them are for pre 94. Currently datamaster did respond and used one of the 20 runs. Did not know it was even running and could not find log file afterwards so trial and error is not the greatest method. I have been using PMCOMM for just monitoring and seems to work OK. I'm happy just to get that going. I really wanted to get FREESCANN to work but so far it imports data but won't record or process it. The MOATES program I did want to use but after couple emails they told me it would not work for the 94, so it sounds like the shows over for them.

I currently am building the MAX232 circuit. At this point I dont see why but I am going to finish the project anyway. The Logic levels should be better and more stable and hope (???) it might make a difference in some of the programs operation and stuff I’m playing with. I have looked at the logic levels and the DC restoration point is where it just wants to be because the circuit has no bias on the transistors and only turns on by the pulse levels. Otherwise there is no conduction, its a real bare bones circuit but does work. The MAX232 provides isolation and standard industry output levels.

I have not tried TunerCat yet so I can't comment on that. As far a reprogramming, I think Datamaster will do that but I’m not currently knowledgeably enough to attempt that. I really have no documentation on that yet and will just be happy for now if I can monitor and get things under control. Need to be real careful when reprogramming. Charge on.

 

Thanks mate, i just got home from work and im about to start working on the cable now.

I finished awhile ago, when the sun comes up ill give it a test fly

 

Datamaster is a scan tool not a programming tool. The two main programming tools for our cars are tunercat and lt1edit.

Very true. If you plan to do much programming (like, more than once) then be prepared for the day when you have a failed download. You will need to send the PCM for repair or replace it. The best thing to do at that point is to have the flash chip socketed so that you can program the chips externally in case of a failed download.

 

Ok, i made the cable last night, just tested it with DataMaster, it seems to work perfectly fine for the most, but every so often if the DATA OK pane will flash red and say DATA ERR. This happens in the blink of an eye, im not sure if it is normal or not.

 

VIS - Thanks for the response and keeping me straight. This is the kind of info I need to file in my head. Thought I read somewhere you could program with Datamaster but I guess you can't. Would sure like a good book or documentation on reprogramming to be better educated. I work in electrical enginering, have the ability but not the knowledge in this area and know enough not to wing it.

 

a side note, the cable will not work with a serial-USB adaptor. It detects the PCM but says something about it may be an unsupported version.

 

I wimped out and just bought an ALDL cable last week from TunerTools.com. I usually enjoy the challenge of DIY, but sometimes the parts cost as much as the pre-built, and many times the trouble shooting a bad circuit is painfull.

I got my '94 talking to DataMaster, and logged a 0-110 mph pass. It showed I had 7 degrees of spark retard in first and 5 degrees retard in second. No more retard in third or fourth. That was with 93 octane pump gas. Another item of note was that the rpm bobbles in third and fourth above 5200. I suspect my ignition is breaking down at these upper rpms. Anybody else have other ideas?

I like the flexability of DataMaster to graph any 4 signals that you choose. I just wish it would allow saving the screen as a jpg so I could post it for reviews. It also has some cool features like 1/4 mile estimator and a dyno function. My car runs 8.7s in the 1/8 mile and the software predicted an 8.66 and 13.47 in the 1/4. It looks a little fast considering I spun off the launch, but it's not off too bad.

My short term and long term counts were very consistent at 128, so I think the A/F ratio is in good shape. The only mods to my LT1 - M6 are long tube headers and no cats. I don't even have a K&N filter.

Clyde

 

Not too sure there on what would be causing the high RPM issue, but ignition could be worth a look at, probably time for new leads or new coil if you havent done so recently. Glad to here your bought cable works well with DataMaster