jayroc

I got it to start before, but now suddenly it doesn't want to. It's been a month since I tried before, though.
I attached my MSQ and log files. It's doing some strange stuff, I think it could be a hardware problem, but I'm not sure. The hardware is a v2.2 board, v1 proc, 029t firmware, version 1 error daughterboard for ignition control. Goes into my harness via a custom cable I made.
Also, my TPS stopped working for some reason. It did before, then I adjusted it the other day and now MS won't even see it move... Stock ECU does, though.

It won't let me attach so here are the links to my files.
The only changes in the logs are the first two use the 024s wheel decoder and the last log uses the 25 type decoder setting.

MSQ:
http://studentweb.eku.edu/jason_wilk...20settings.msq

Log1:
http://studentweb.eku.edu/jason_wilk...t%20attmpt.xls

Log2:
http://studentweb.eku.edu/jason_wilk...art attmpt.xls

Log3:
http://studentweb.eku.edu/jason_wilk...%20decoder.xls

T2GTUS

Did you warm it up on the stock ecu? (If so your cold cranking p/w's seem more inline than the 160+)

muythaibxr

What other strange stuff is it doing? How did you wire it in? spliced off the stock harness wires? Sounds like some of the splices might have come loose or something.

jayroc

Yes, I did warm it up with the stock ECU.
The strange stuff it's doing is the RPMs don't seem to be registering correctly, the TPS isn't acting the way it should. Guess it doesn't constitute a lot of strange behavior..
Everything else seems to be reading correctly.
I'll look at the wiring again. The way I have it wired is the custom harness cable in the pic.

muythaibxr

RPMs not reading correctly can be any number of things, although when it does it on crank, it's usually due to poor grounds. The MS is sensitive to this.

The TPS not acting right makes me want to suspect bad wiring or a short circuit, which could be what's affecting your RPM display as well.

jayroc

I'll look at the ECU grounds.. Found the TPS problem, left it unhooked after I readjusted it yesterday. oops

muythaibxr

well, that would be a wiring problem wouldn't it

jayroc

Well, I ohmed out the pins, they don't seem to have a problem.
I got the MS grounds tied together and grounding to the stock ECU case mount for now. Same problem.
I was reading in another thread that I may need to adjust out the G potentiometer? Right now they are both set at 0 ohms.

The error daughtercard is grounded to JP1's ground pin, which ohms to the same as the outside ground on the cable.. Is there a special trick to this?? I should be getting RPM readings or something at least. Spikes would be okay at this point.. lol

jayroc

Okay, I got it. Apparently, the little blue potentiometer needs to be set to a certain resistance..
I set G's adjustment to 20k ohms or so, and Ne's to 0 ohms. That seemed to do the trick. It's idling well and I took it for a test drive.

It is pretty frustrating to know you've done everything right, then something like this trips you up.. I bet more than a few folks had similar troubles with these little pots... Oh well, it's all good now.

I don't suppose anyone with a stock 13b using the FAQ settings would like to share their VE table to get me a better starting point? I'd appreciate it if you could.

muythaibxr

Ahh, I hadn't considered the potentiometer on the G signal. That shouldn't need to be adjusted unless you have wiring problems. I don't think the area you chose to ground to (the stock ECU case) is good at all as a ground.

I strongly suggest grounding to the engine.

jayroc

I should say that this is not my only ground. For the MS I am using 3a and 2r (iirc) from the harness, but started experimenting by adding this other ground for the error daughtercard when it wouldn't start. The "grounding faq" in the FC section mentions to tie all 4 ECU grounds together and ground at the spot I picked, so I thought it was cool..

In the engine bay, I got a ground wire going from the battery to the firewall, strut tower, and starter, then from the strut tower to the engine.
I could rezero the G potentiometer and reground to the engine directly, I suppose.

muythaibxr

my suggestion is to have engine grounds to the chassis in several places, and have the battery ground to the chassis, then have the MS ground to the engine. If you chose those 2 grounds on the stock harness, they alone should be enough if the rest of your grounding is good. If not, you can cause things like ground loops, which wreck AC signals (which explains your need to turn the pot on the error* board). I personally have never needed the pot on the error* board, and nor have any of my customers, so I removed it, as it's one of the most expensive parts on our daughterboards.

Aaron Cake

iTrader: (1)

Here's the ultimate grounding article:

http://www.aaroncake.net/rx-7/grounding.htm

57bronco

That's by far the best grounding article I've seen.

muythaibxr

you basically just said in that article what I usually tell my customers when they have problems... clean up the stock grounds...

IF I build my own harness, I usually try to duplicate the factory grounds, but possibly with one guage thicker for the wire. When I was saying how to ground earlier, I basically was describing the stock setup of just about every car I've worked on (rx7's included to a point... they're slightly different). The factories knew what they were doing, and usually following what they did keeps things working better.

Aaron, I'm going to put that grounding writeup in the FAQ. It IS the best writeup I've seen on the subject.

Ken

jayroc

Yeah, good writeup. Thanks, man.