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-   -   trying to get my car started with the new MS2 (https://www.miataturbo.net/megasquirt-18/trying-get-my-car-started-new-ms2-59008/)

SleekBlackBeauty 07-10-2011 06:07 PM

trying to get my car started with the new MS2
 
My MS2V3 built by Reverant has a problem or two. The car doesn't start. There may have been a problem with the transistors running the injectors but that is probably fixed by Braineack who was very helpful.

I recheked the injectors with a test light, they work fine. I did not test the spark plugs to see if they fire, but previously they did.

One big problem seems to be that it does not run the fuel pump. I thought before it did, but this time, I hooked up my friend's fuel pressure gauge and there was no pressure at all. The MS does not operate the fuel pump. It works fine with the OEM computer, the car otherwise runs perfectly with that.

We jumped FP and gnd and ran the pump. There was some ignition, but it was irregular and the timing seemed way off. The car pooted and chugged a little and almost backfired. But no start.

So there seems to be both a hardware and software problem, but now there is actual information. :) I think I recorded a data log, but I haven't done that in a while and I need to look at the laptop later to see if that came out right. I will upload it if it looks usable.

So...Dimitris...you might have to talk me through repairing the fuel pump driver circuit, but for future tests, I can run it through the diagnostic port.

Reverant 07-11-2011 01:55 AM

Well lets check the ignition again, do the spark test through the output test mode.

SleekBlackBeauty 07-16-2011 06:56 PM

Hmm. Today I found time to run in diagnostic test mode. Coil A ran plug 2 and coil B ran plug 1. The output test did not run the fuel pump at all, but it did work again only when jumped at the diagnostic port. So far these are promising leads.

Reverant 07-17-2011 03:48 AM

Coil A should run plug 1 and 4; Coil B should run plug 2 and 3. So you definately need to swap these around.

SleekBlackBeauty 07-17-2011 09:29 AM

I switched the wires and manually ran the fuel pump. The car had some combustion here and there, an occasional chug without really coming close to catching, and I smelled some unburnt gas. It did not start. I did a datalog, but I can't seem to recall how to locate it to upload. It's odd, because I looked at it. I need to figure that out.

Not sure what the next step here is. Is this ever going to work?

Reverant 07-17-2011 12:14 PM

Now that you switched the wires around, can you confirm you have spark on 1&4 when testing coil A, and spark on 2&3 when testing coil B?

SleekBlackBeauty 07-17-2011 12:56 PM

Hey! Success!! I fiddled around with it this morning, and keeping the fuel pump on and with the spark plug wires switched, I was actually able to get the car started! It wouldn't idle, but it started! As soon as my foot released the accelerator it stalled. But it started a couple times!

The timing must be off as when I ease off the gas to 1000 rpm it runs roughly and stalls at about 800 rpm.

This is good news!

Reverant 07-17-2011 04:00 PM

There are couple things you need to dial in to keep it happy and idling - like calibrate the TPS, give it enough air at idle (either through the bypass screw or through the idle valve), give it enough fuel - it may also be lean at idle, so give it some fuel as well (start by adding 3-4 units in the cells below 1500rpm and below 50kPa).

SleekBlackBeauty 07-17-2011 04:14 PM

Excellent, yes. (The TPS was already calibrated by the way.)

Does the autotuning feature help that? I am still running basic tuner studio, it seems time to buy the full featured program.

Unfortunately I need to use the car now, so I will have to put things back, unless it is fast to adjust and I could actually drive it right now.

Reverant 07-17-2011 04:17 PM

I wouldn't recommend doing things in a hurry.

SleekBlackBeauty 07-17-2011 04:18 PM

:) Good advice! Or in the dark, I have made several mistakes that way.

Braineack 07-17-2011 06:52 PM

(zack morris's phone)

Swapping fuel injector at night without a flashlight is simply humorous

SleekBlackBeauty 07-17-2011 07:06 PM

I did exactly that not long ago. Leaked a gallon and a half of gas until I had time to fix it. I had put in the 4th injector a little awkwardly in darkness and tore the tiny gasket at the top.

Braineack 07-17-2011 07:57 PM

yep exactly what we did. lol! started the car and fuel sprayed all over the damn place.

SleekBlackBeauty 07-17-2011 08:40 PM

Any suggestions on fixing the fuel pump issue? I would like to get that running before I start tuning. I am only able to get it going with the diagnostics port jumped to ground.

Reverant 07-18-2011 02:29 AM

Scott did the fuel pump work on your stim?

Braineack 07-18-2011 08:38 AM

Pretty sure it did or I would have noticed it if wasn't, but not something I really took notice, so I can't say that with confidence.

Reverant 07-18-2011 11:43 AM


Originally Posted by SleekBlackBeauty (Post 750260)
Any suggestions on fixing the fuel pump issue?

Can you confirm that there is a violet wire coming from pin 37 on the DB37 connector to pin 1U on the blue connectorboard?

SleekBlackBeauty 07-18-2011 11:42 PM

Yes. Everything is correct and attached to the right place in the harness. I opened up the plug and looked at it, and could easily trace the violet wire from one end to the other.

SleekBlackBeauty 08-01-2011 11:40 PM

Hey gents, I'm all geeky excited, have the MS installed and I'm driving. It's running pretty well, still needs some tuning. Working with ts and am experimenting with ve live. So... I'm pretty happy overall. Except, I really want to deal with the fuel pump circuit. Multimeter confirmed that the wiring harness is ok. How shluld I go about approaching the ms unit itself? Point me in the right direction and i will look into it and maybe get help from engineer friends I have. Not having built this thingy myself i could use a couple more hints about the picture and correlating with the wiring diagrams.

Thanks again to Reverent all who have helped me so far!


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