S14 KA24DE won't start now...starter or hardware problem?

[klattr1]

I've had some miscellaneous issues leading up to which I'll get to below, but as of tonight, I can't connect to Consult via Nistune nor will my car start (starter won't even turn over).

Car has been running on Nistune for a little over a year and is my daily driver. Setup is a 1995 240sx KA24DE (M62 supercharger, 370cc injectors, Q45 mafs and TB).

I drove my car to work this morning without any issues...the car sat for 8 hrs while I worked and then it took several times of turning the ignition with the gas to the floor before it started (I thought in my head it may be a cold start enrichment problem but it's never been an issue up to this point). Well I got it running and drove it all the way home...when I pulled into my garage, I turned the car off and tried to start it again and no luck (ignition and dash lights do come on but starter doesn't turn over).

My car was doing this randomly months ago and I ended up installing a brand new starter (thinking the old one was on its way out). Now I'm having the same issues again with a starter that's not even 4 weeks old. I have confirmed that 12v gets to the starter (as well as it being distributed to ECU and other accessories) but I haven't removed it yet to see if it will spin over on it's own. It seems as if it tends to not turn over after the car has been run for a while and is hot...example: I did a 350 mile road trip 2 weeks ago and car was driving fine and I pulled into a gas station to fill up with gas...after filling up the tank, the starter wouldn't turn over at first...It took several (like 20 times) tries to get it to start up.

What seems weird to me is that I'm now having issues even connecting to Consult. Not sure if that's another issue going on or coincential with my other problem. I've reinstalled Nistune/Rom packs several times and reinstalled drives, still no luck. Not sure if there's a hardware problem, software problem or an electronics issues somewhere else. I have confirmed that the battery and chassis is properly grounded as well as the stock locations on the block, head and intake manifold.

And this may be unrelated, but the car used to be an automatic (previous owner converted it over) but now is a 5-speed. The car would normally start even without the clutch pushed down so I'm assuming the clutch switch isn't installed...from what I can tell in Nistune, the ECU is still an automatic 95 model.

Attached is debug log for Matt or Pete. Any ideas?

[Matt]

I'm a bit worried that your car is not cranking. I was originally thinking if there the possiblity that the engine is flooded and it wont turn over because the cylinders are full of fuel, but the cranking problem occured after driving it home.

My suggestion still is to pull the plugs and check if fuel in the cylinders regardless just to clear that up. If that is okay then what if you put 12V directly onto the starter trigger wire (usually just pull plug off and put 12 volts on there)

As for the connection issues, sounds like your ECU has gone limp mode. You can check our 'diagnostics and communications' document on the website to run through and check. If your vehicle is hard to start and overfueling now then sounds like the ECU has gone limp

Next thing to work out is if installation issue or board. Thats going to be the tough part. If there was a dodgy soldering joint then reflowing and checking should help. To check your PC works, remove the board, move jumper to factory mode and see if consult connects

If the ECU works in factory mode, recheck your adaptor connector soldering (particularly 1,39,40 pins)

[klattr1]

Well it ended up being the starter. I probed both the big 12v terminal on the starter post as well as the 12v coming from the harness that activates the solenoind...both were functioning as normal (permanent 12v on one and 12v when turning the key on the other) but the starter still wouldn't spin over. So I removed the starter and took it back to the parts store and they bench tested it there and it magically starting working again...So it sounds like it was an intermittent issue. But they warranty exchanged it and I got the new one in...voila!

So yeah I got the car back and running again and now can connect to Consult but...the only issue I've noticed when watching the Consult gauges is that it seems to lag/freeze/stop reading if I rev the car up and hold it at a certain RPM (like 3500 rpms)...it's like it's getting noise in the USB cable or something at that RPM. But when the RPM's are low, it doesn't seem to be an issue.

Any ideas? I've read the diagnostics manual on this issue and have confirmed that the battery, block, head and intake manifold are all properly grounded. My battery is relocated all the way in the back though (and that's where the main ground exists). Maybe I'll try routing the wire to a different spot. Do I need to be using a higher quality USB cable that's less prone to noise? If so, which brand/model do you recommend?

[Matt]

So you have ground wiring going from the boot to the engine still? Got to be associated with that. So grounds are shiny clean?