Grounding wires might be causing me trouble.
 

So today, i reinstalled the megasquirt after pulling it out for inspection. and going over some of my wiring. At first it wouldnt start up at all and so i Thought I would check my grounds. I moved the engine to chasis ground from the block to the oilpan dipstick because that is how it was on my 97' and Ive had the engine out before so i may have put it back wrong. Finally soldered on my CAS wire to the harness for good. Ok so i guess my temporary fix had not been making very good contact. So i was pretty happy for a minute until suddenly it died on me. Started right back up afterthat and i though ok just a hiccup or something. Wrong. Got it around the block and it died for good after that.

Anyway can someone with a 90' let me know where the groundstrap under the TB cable (where it comes through the firewall) should be attached? Also, the two grounds on the back of the intake manifold might be mixxed up as well, but i dont really see how it would make a big difference if they were.

If it dies after a minute or so you propably need to set your warmup enrichments properly.

No i was able to warm it up just fine, thats what i thought too but its definitely not warmup enrichment. What i was experiencing was running perfectly followed by suddenly cutting out all fuel and shutting off or almost shutting off. Now I cant get the car started at all.

I have a question for the other megasquirt guys on here: How did you attach the ground wires in your install? There are four ground wires and I was curious if it might be causing some noise having the black/ltgrn and the black wires grounded to the same place. Maybe I should just ground black to the frame instead?

originally I had every ground going to 4D, i changed that this w/e gone and split them half and half to 4D and 4C

4d goes to the front engine earth and 4c to the rear endine earth (I think...)

I had a weird missfire that was really random, and so far it's cured.... *touches wood*

I also removed about 100ft of wiring.... I used a 6ft wiring loom, I really only needed 6" :eek4: The passenger footwell has gained about 2 inches of legroom in the process, and I might finally be able to install the protective plate!

I'm using splices into 4C and 4D also. Good luck, but it sounds like your problems may be bad connections.

Actually I think I did ground the CAS someplace at the back of the engine. I don't know if this is making any difference though.

well i figured out why my car died now. After wondering a bit why my stock rpm gauge went out at the same time, I remembered that the stock gauge is triggered from the coilpack, duh. It must have blown when I stepped on it a little more just prior to it dying around the block. Popped my spare coilpack in and she started right up ... then randomly died again. It looks like there is a grounding issue and I will have to go through all the ground points in the car to get it working right and to not blow another pack ... which would piss me off a lot because i want to get this all working without spending any more money.


Anyway, It never occured to me before, but the whole time before when I was misfiring, the stock engine gauge would flutter and I could never figure out why. So if there are any suggestions, I could really use them right now. I have hope again that I can get this thing running well, but im not holding my breath quite yet.

And yes again, i could use some help in the form of suggestions

Is it possible for you to revert back to the stock ECU for a little bit? If you do that you could possibly rule out the MS being the problem.

not possible without way too much trouble, i have cut into the harness and would have to splice wires back in to make it work. only as a last resort would i do that.

How do your datalogs look? Do you still have all those yellow vertical lines? I put female connectors on the spark outputs of the MS and stock ecu while getting it running, I had to switch back and forth a lot and it made a big difference in giving me some direction in tracking down my problems. i think it would help you decide if it was something in the MS or something in the car's harnness/grounds giving you trouble.

Have youtouched your ignitor while running? Does it get hot?

hmm is the ignitor one of those things on the drivers side of the engine bay marked LA10 and LA12?

Ok so i went over all my grounding and wiring, checked all the plugs, retightened some of the bolts on the valve cover that had wiggled loose, bolted the new coilpack on and started it up. At first, it shut off after about 10 seconds. Then I set it up to take a datalog and started it and it did not die during the 5 minutes of idling that I recorded. I am nervous about taking it out on the street much at this point because i really do not want this coilpack to get messed up.

After the 5 minutes, the coilpack didnt feel hot at all really, it idled nicely at 1.0 injector openening time which is a first, however it required a bit more fuel than Al's map at 4.9 reqfuel. Ill mess with it a bit more this weekend. God i hope that my troubles are coming to an end.

Good luck. The ignitor is the little black thing with a bunch o wires comin out on the passenger wheel well. has a mitsubishi logo on it.

Just so that you know: I had problems the other day, with my car stalling in the middle of the highway. Turns out it was the RS Autosports wiring harness. I bought my MS from Bill Shurvinton in the UK, who propably gets the stuff from RS. Well, the RS harness is propably not very well crimped on the DB37 connector and the most important input signal, TACH, is messed up. I will open it up within the next few days and solder/hot glue the living hell out of it.

Jim

thanks reverant, i dont know what happened between now and earlier, but I tried to start the car tonight and ... damnit no rpm signal again??? Anyway i have another db37 that i made and didnt use. I bet the connections are better on that because i soldered each pin individually and shrink wrapped each one. I really need to clean up my wiring anyway. who knows, maybe that will solve my problem.

Anyway, I really hope that my coilpack is still working right ... it really wouldnt make sense anyway because i had it idling for 5 minutes earlier and shut it down without an issue ... theres something else going on.