Thanks for the info renns.

Is that to say that these sensors should be grounded back to MS or is the engine/chassis an OK ground? I would have thought that keeping my ground runs as short as possible would help keep signla interference down.

Also, do you have any advice for wiring up the fuel pump ? I'd like to remove my MAF sensor as of right now I have to leave it on otherwise my pump isn't being activated via the factory circuitry.

 

yeah, I figured he was just looking on the ECU side for the wires... and seeing only one wire for the air temp sensor and coolant temp sensor.

but yeah, if your sensor numbers bounce all over the place at any time, then your grounds could be messed up. I saw this once where the MS had been grounded to the chassis under the dash. Every time the brakes were hit or anything similar, the temperatures would change. Grounding the MS properly fixed that problem.

 

I've grounded my MS to the battery. My harness has 2 main grounds on it which I ran both to the battery, perhaps I should move one to the engine ? I've redone my main grounds on the car, replaced the engine/body ground and the battery/engine ground.

I've broken one of the connectors of my Intake air sensor so I'm trying to get another, and I know without this sensor it will add tons of fuel thinking im in arctic tempretures, or atleast thats what the factory ecu would do. I think once I get my grounds and sensors straightened out I should almost be ready to get idle working. Which leads me to my next question, what should I be doing for idle control ? I still have my BAC valve connected is it advisable to use this ?

 

You CAN use the BAC valve, but it's not necessary. It's mainly useful for if you still have AC and stuff like that.

I would NOT ground the MS to the battery. I've had at least 2 or 3 people who did ground stright to the battery have weird noise issues. Technically it shouldn't cause a problem, but the emperical evidence shows otherwise. I've had the best results from grounding the battery to the chassis, then ground the engine to the chassis, and grounding the MS to the engine. (that's pretty much the factory configuration).

 

The oem's ran dedicated ground wires back to the ecu. I'd recommend doing the same.
There's a fuel pump test connector (yellow 2 or 3 pin??) by the passengers strut tower. Short those two pins, and the pump runs regardless of MAF sensor position. A very simple solution would be to use your MS fuel pump relay to short the contacts on the test connector. It may also be possible to connect MS directly to this connector without the separate relay.

As for grounding, here's what I've done on my installs: Buy an M8 brass bolt, nut, and two flatwashers from the local hardware store. Drill a hole (or use existing) in the firewall. Connect all MS grounds to this bolt on the cabin side of the firewall via heavy gauge wire. Run another heavy gauge wire from the engine side of this bolt to a nice clean spot on the engine somewhere.

Roger.

 

I ran new grounds as per your suggestioni renns and replaced my IAT gauge and wired to the correct coolant sensor and my guages are reading true and no more irratic reading. I couldn't get it to idle last night, it was still all over the map, hard to start and once running felt like it was runnin on 1 rotor again it felt like the timing was so far retarded it was bad. I stabbed the CAS at the 3rd tooth to the right of the of the 2 tooth gear lined it up with the bottom reluctor (24t) and set my decoder settings to 1,3 7,9 but like i said it would barely run. I'm running G+ and G- on the factory sheilded wire, Ne+ is on my own sheiled wire but Ne- is on a normal peice of unsheilded 20 ga wire. My tach signal seems clean I didn't notice it jumping around. I suppose my next step is to share some datalogs for you guys to look at and see if there is anything obviously out of sorts with my setup ?

Tonight I am replacing my CAS wiring with a new peice of shieled for all 4 wires.

 

That's not a good place to run the MAP sensor from what I've been told(erratic signal).The one to use is one of the 3 (bottom one) on the back of the intake plenum by the TPS (13BT). You may also need to further condition it by using a restrictor such as "mig tip" and a small "buffer filter" like the 3rd gen uses.

 

I'm actually using the same one that the factory boost sensor uses... I just removed the map line from the factory sensor, and put it on the MS, and I've never had a problem with doing that.

Basically, I think you're running poorly because you haven't properly set ignition timing yet.

Also, did you set the proper trigger angle? You should be running 60 degrees for your trigger angle.

Finally, you should set the "fixed angle" to -5, and using a timing light, turn the CAS until the marker on the e-shaft pulley lines up correctly. After that, you can reset the fixed angle to -10 and you should be all set. Using a timing light is essential though. If you just stab it and hope for the best, you'll never know if the timing is exactly right.

Ken

 

I'm not sure if I can keep it running long enough to set the timing at this point.

 

Can you measure it while cranking? Worked for me.

 

I replaced my CAS signal wires with all shieled. I got a timing light and noticed that I had no signal when connected to L2 and it seemed to be intermittent with L1 although when testing for spark when I spun the CAS I got spark on both L1 & L2... Odd but in the end the car was too flooded to turn over so I pulled the plugs and cranked it over and watched the cloud of gas escape. I am going to get a little oil squirter bottle today and some atf to squirt into the housings to hopefully allow it to fire. I didn't realize you could flood it so bad that it wouldn't even fire.

Needless to say, this endavor is prooving quite challenging, I am getting very discouraged at this point that its ever going to run. Im not ready to give up though.

 

don't give up, the first time tofuball and I got his car started, it took us several days working on it each day to find all the little problems and get rid of them.

we were working on it once per week at that time, and for about 4 or 5 hrs per time we worked on it, and I think it took us 2 times working on it to get it started and running, and another time to get it to set the proper timing (this wasn't with the wheel decoder, we were running a hacked HEI module setup at the time) and yet another time to get the grounds right and make it reliable.

 

You may very well need fresh leading spark plugs. I went through several sets getting my MS going. My local NAPA carries Autolight 2626 plugs for ~$3 instead of $6 or $7 for the NGK plugs.

 

I will hit up napa kuz the last set of NGK's i got were $14.99ea with discount !! I found that I've got more grounding issues last night, it seems that my battery ground was iffy so I've added another battery to chassis ground and that seemed to make my spark more steady. It was odd, when I'd connect L1 i'd have no spark, but then when I'd pull the lead out stick a plug in and ground it to the strut tower i had spark, timming light flashed too when cranked. Put it back no spark? what gives, figured poor battery ground, so adding the battery to chassis helped. By then I was tired and only cranked it over and got some sputtering but there was life, I left the plugs out over night yesterday so they were dry when i put them in yesterday so i'd figured they'd be OK, but once a new set is fouled they are no good ? I figured if you let them dry out they'd be ok.

 

Nope, it's pretty common that fouled plugs won't come back. I think they get a carbon track laid down on the porcelin that shorts out, preventing the voltage build-up necessary for a spark. That's why your timing light isn't firing, too. Same thing happened to me.

When you put the fresh plugs in, pull the ECU fuse and crank it with both plugs removed. Cleans most of the excess fuel out of the "cylinder" so you'll be less likely to foul the new plugs.

Oh, BTW, don't bother changing the trailing plugs until you get things running pretty well. They don't do much, and no use spending double.

 

well some news, I initally set my timing last night and was able to get it to start and run (roughly) for about 20 seconds then stall. This is as close as i've gotten to a stable idle, the idle while its running is not great but its the best its been yet. I still have to set my timing properly i have it out about 5-10 degrees right now but I am in much higher spirits now. All my problems so far have been ground related. I think it really needs to be stressed how important all your grounds are when doing an install.

I suspect its stalling after about 20 seconds is either too much or too little fuel.

 

that could be when your afterstart enrichment ends... although that seems like a long time for afterstart enrichment.

 

20 seconds is a rough estimate, ASE is 200 cycles ? how long is a cycle ?

 

no idea?!

 

Thanks for the helpful post. There is no post ***** emoticon so this is all i could find.

 

A cycle is 2 rotations of the e-shaft, so 200 cycles is 400 revolutions. At ~ 1000 rpm, your right around 20 seconds. I'd bet you are lean due to either lean VE table, or low warmup enrichment values. Do you have some base map/settings you are using, or are you starting right from scratch?

You should be datalogging during these start attempts. If you have been, then open the datalog with one of the log viewing programs. Look at the point of stall, and see if pulse width was increasing or decreasing just prior. That'll tell you whether the stall event was rich or lean. Then take a look at the run status to see if the stall occurred just as AfterStart Enrichment completed. If you need further advice, post the datalog here.

You've likely already done so, but don't forget the tuning documentation at megasquirt.info. This forum is a great help for rotary-specific stuff, but it should be used as a supplement rather than replacement for the existing docs.

http://www.megasquirt.info/v22manual/mtune.htm

Roger.

 

Agreed, the tuning docs over at megasquirt.info are some of the best out there. Which is why I haven't tried to duplicate them here.

I'll probably add some links to the official megasquirt.info site for the tuning docs on the FAQ.

 

well im in business, up and running. I am in the tuning game now. I've got a pretty good idle but I think i need to add some more fuel. I'm workng on my VE map right now I am getting some detonation around 4k under light boost. Thanks for your guys help its nice to finally be running and driving. I'm hoping to get around 300 rwhp on my setup. Once I get familar with tuning I will get on a dyno and see what kind of numbers I can really get. Thanks again guys.

 

yeah, if you're getting detonation, add fuel, reduce timing, or do both. Other than that, glad to hear you're up and running.