vwdave

Namely Me. I am a Prom virgin wanting to pop my perverbial cherry.

I am trying to datalog my 89 RS that has a mild 350 TPI in it. (90-92 Speed Density) I need to figure out how far the tune is off. It seems like its "Power/Cooling Efficiency/Mileage, pick 1. I dont mind if it was balanced. I am not expecting 20mpg and 400hp. Just the damn car to run right!

I am also using TunerPro RT, and a moates cable on a brand new laptop with XP. I CANNOT get the laptop to connect to the computer. I finally got it to say "Connecting" but will NOT connect. I try going between the 3 toggles, one of them makes the DTC light on my painless harness flash steadily. Am I doing something wrong? Or is it my software? Setting? HELP!

Should I use a different datalogging software and then buy a software to modify the bins? Like I said before...HELP!!

dimented24x7

iTrader: (2)

Cant help with the cable but...

Cant really pick one. There are some things you can do to help improve economy a bit but generally its more dependant on what combo your running. Just tune it right and whatever fuel economy it gets when your done is what it gets. I origionally got into prom burning to save money on fuel but the exact oposite happened. Actually used more gas by the time I got done. Runs alot beter, though...

As far as cooling, theres not much to be done on the engines side other then making sure your running the correct ammount of timing. If the cooling system cant keep up then the cooling system is just inadiquate for the engine.

vwdave

I mean it gets sub 5mpg.

It was initially running lean, and overheating the car. I richened it up and that fixed it. I might back the timing out to stock specs. (8* to 6*.)

dimented24x7

iTrader: (2)

5 mpg is really bad. What is the fuel pressure set to? What injectors are you using. Almost sounds like a possible non-tune related problem.

Ive never used any of the P4 ecms so I wouldnt know how to connect to it to datalog. Maybe try other datalogging software and see if you can connect with that.

vwdave

I set it to 47psi and it ran pretty good. I tinkered with it and it started running like crap again.

22lb injectors and a walbro 255 fuel pump.

JP86SS

iTrader: (1)

The datalogging should connect (without the A & B jumpered in the ALDL) to pin M or E on the connector using the correct "ads" file.
This sounds like the ECM is running in "limp" mode and not from the prom. When mine did that I couldn't log any data either.
Check if you can get any codes from the DTC light when jumpering A&B. Also see if you have the actual data pin connected in the harness to the ALDL (maybe not??).
you lost me on the "3 toggles" thing, not sure what you meant.
If your fuel pressure is that high with the stock injectors, limp mode will run badly and be putting more fuel in than what is needed. ECM is set for stock injector size and with the increased fuel pressure they will be bigger than stock. You may want to adjust it back down (if its easy enough) to get a smoother running engine for now.
First things first though,
Check to see if your TPS, IAC, base timing are set correctly.
Without knowing you could chase ghosts easily
Do a search here to find the procedures, they are listed in many spots.
BTW, I'm ASSuming you are using a 730 ECM in there.
Check to see if the memcal has come loose or something simple like that, loose power wire etc.
You might get lucky and find something obvious.
Jp

Kevin Vandevenne

iTrader: (3)

I have a 91 GTA and I am having the same problems. I just bought a cable from Moates, and have tried various software, but I can't log any data. With the cable hooked up to the laptop, the DTC light does flash. Car seems to be running pretty good. I tested the USB port on the laptop, and it is working ok. Not sure what else it could be, I'm new to this as well.

dimented24x7

iTrader: (2)

What is this 'DTC' light on the painless harness that you refered to, vw? Is it like the SES light?

vwdave

Yeah.

To the guy that posted earlier. Thats interesting. I have a MAC Mentor Scanner and havent noticed any problems or codes. The car runs pretty good by listening to it, but the car doesnt have the chassis twisting ***** it should, and the mileage is horrible. When the car is too lean, it overheats.

Its a 7730 ECM with a 91 1LE Prom (dealer part) Its a bolt-on 350 TPI. Headers/Exhaust, ported upper intake, K&N's, 8* timing and LT4 standard cam.

JP86SS

iTrader: (1)

DTC "Diagnostic Trouble Code", SES is called that sometimes.
Same thing.
The 3 toggles you mentioned, Do you mean a switch on the cable box or something?
That might be the A & B pins connected through the switch for ease of use.
For normal logging on the 730 it should be "open" or not connected.
When you connect the A & B pins on the ALDL the diagnostic codes will flash.
Best to do this with key on and engine not running.
You will get code 12 if the system is operating correctly.
This means the distributor is not outputting pulses to the ECM(the engine not running will do that, its normal to see that)
1 flash...
2 flashes..
Will repeat 3 times..
next code will then flash (if any)
Then when 12 repeats, all codes have been displayed.

If you get a constant light or just continuous flashing then something is wrong and you'll have to start looking deeper.
Hope this helps.
JP

Kevin Vandevenne

iTrader: (3)

Thanks for the info. I will have to check it tomorrow when i get some time. I seem to remember it was a constant flashing when i had it hooked up, but I will need to check it again to be sure.