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General No Start with MS3X (420A)

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PopNSnap

Probationary Member
12
2
Oct 8, 2019
Mountain Home, Arkansas
I'm still new to this so please be patient with me. I'm working on a 1996 Eclipse with the 420A/5speed. We installed a MS3X ECU in this thing and can't get it started. We pulled the fuel rail and found that the injectors are 30lb Accels. Using the stock coil pack with resistor type plugs. I have it set on batch fire for now to eliminate the cam sensor as a problem. I really don't know anything about this long block, the customer says it's been stroked and/or poked so it's no longer a 2.0. I'm getting fuel and spark, but it's not firing up. Just popping, either through the exhaust or intake depending on what the timing is set at for cranking. I'm not sure how to post a MSQ on here, but I added some photos of the screen so you all can help. I took two of the composite logger, one in Falling Edge and the other in Rising Edge. Any help would be appreciated.

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Input capture should be set to falling edge. And Flip polarity on cam should be normal not inverted. My cranking advance is set to 10 deg.

Hope this helps.
 
Sorry, it's not that simple. I've tried all that. There's no timing belt cover, and the balancer is all chipped up, so if these engines have timing marks, this one doesn't. I spent a lot of time lining the crank cog to it's mark behind the timing belt. OBX cam gears so you can't trust those marks, something I glad I Googled before I took the belt off and reset. Took the valve cover off to make sure they're right, or as close as I could get it. Made my own pointer and marks for the balancer so I can check the trigger offset which was only 2 degrees, which makes me think the needle I made is probably what's off. The internet is all over the place so I've tried all those. I've even tried crank timing from -5 to 15. At around 10 degrees it would start popping in the intake and 15 it really pops in the intake. We've had cranking fuel up until the plugs got wet and took it down a little.

One thing I don't understand is how it's getting sync issues under batch fire when it's only running off the crank sensor. When I get on the compture again I'll post a couple photos of my logs. I had my co-worker take a slo-mo video of the coils firing and looks like it goes ABABAABBAABB. I have no idea what's going on there. I even hooked the shop air to the cylinders to make sure the valves aren't leaking. I'm really at wits end.
 
I got two datalogs here. One with everything as is, I was thinking the dips in the RPM could be from every once in a while the engine catches and fights the starter. So I took another one with the injector fuse pulled so it would have any resistance and the RPM is steady-ish, makes me think noise, but not really sure how to tell. The lines for CLT and MAT are spiky, but when you hit play and watch the numbers, they stay ambient. That seems weird to me. If you need any other photos of anything, let me know. I've been fighting this for way too long.
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I'm not the one that built it, so I don't know what's in it. I think I remember seeing another set of cams in the backseat, under all the trash, so there's no telling. I loosened up the cam bolts enough to see the slots for the dowel, had to move the intake gear 3 degrees to get it vertical. It has a boost referenced fuel pressure regulator, it was around 30 at first and we bumped it up to 45 to see it that helps. Running the MS3X as a standalone, Dodge Omni regulator for the alternator.
 
Ive never heard of someone using the dodge Omni regulator for the alternator on an eclipse especially a 420a... so I don't have much knowledge on that, but I don't think it could be that.... does it run for a bit then die or just die right away or not even start just cranking
and PSI for fuel pressure is from 43.5 to 55psi on these engines just some things to help! this is a doosey...hmmmmm

Symptoms of a Bad or Failing Instrument Voltage Regulator

  1. Dim or flickering gauges. One of the first symptoms of an issue with the voltage regulator is dim or flickering gauges. ...
  2. Inaccurate or erratic readings. Another symptom of an issue with the voltage regulator is inaccurate or erratic readings from the voltage regulator. ...
  3. Inoperable instrument cluster.
 
I read on Symtec's website that they used the Omni regulator, none of their stuff shows any availability anymore, but their kit even comes with one. Other people on other forums have used them, I've even seen old hot rods come into the shop with one on them. It only has two wires (case grounded) and turn the field coil on and off depending on what voltage it's seeing. I really doubt it would cause any problems, I can unplug it next time I try just to be sure. I haven't noticed any dim gauges or anything yet, but I've been remote-starting it from under the hood instead of the key. New, hot battery and I always put the charger on there after a few tries to make sure it stays hot. The battery is in the trunk so I even ran another cable from the battery to the engine, and have all the computer grounds on the same bolt so it's not relying on the spot welds of the unibody for a good ground.

It doesn't start at all, just pops and snaps while cranking. I went through the test modes to make sure the injectors, coil, and fans are working properly before I even tried cranking for the first time. When I did the composite logger I found that the cam sensor wasn't synced with the crank so I wasn't getting RPMs. Research has shown that the magnet on the cam probably has to be rotated 90 degrees, but instead of doing that I just switched to batch fire to get it out of the equation, then I was getting RPMs, fuel, and spark. Tunderstudio has an option for Chrysler ECT and MAT sensors, and so far they've been matching up with my thermometer. No one around here has even heard of Megasquirt so finding local help is impossible.
 
the connection for the cam position sensor should be facing at 45 angle toward the firewall so if that's not the way it is in the pic then it's possible that's the problem

this is what mine looks like lets reference that first
 

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I don't run a turbo which im assuming you probably have, but I know my cams are setup with a decent overlap (gives a lumpy/boggy idle) for natural aspirated engines the way I have mine set is for higher RPM range but that's the fun about adjustable gears you can set it up how you want it i use this as a reference sometimes took me a while but i eventually learned what to do! LOL :)
https://www.hamotorsports.com/cam-gear-tuning.html

they look like this the first pick is the intake cam and the second is the exhaust cam
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It has a turbo, but I didn't bother hooking up the intercooler piping yet, it's pretty Mickey Moused. I'll get some photos of it tomorrow. My cam gears marks are 90 degrees off like in a Youtube install I saw of someone installing OBX gears. I don't mind taking the valve cover off again, I'll get you all photos of the lobe placements. I really appreciate all the help.
 
That's what we are here for, I know there are still a decent amount people running the 420a platform but it's always hard to find help

also sometimes I flip flop the setup by (retarding the intake - advancing the exhaust) this gives me killer torque to the wheels but horrible top speed I like the setup in the pic's it has good top speed and killer get-up for a N/A motor. I cant wait to turbo it see what else I can get out of it before possible swap for EVO 8 motor. that will come with time not in a hurry for that.

after pulling out my old stock cam gears the 609's need to face each other so that would put the intake dowel pin at 6 o'clock and the exhaust dowel pin @ 12 o'clock

I installed my cams at 12 o'clock on both and it fires up and runs/idles good but it very well may be the cause of why it cant keep the engine running while letting of the gas from a higher rpm to a stop so I'm going try the other way on friday and see if she fires up and drives without the stall problem :banghead::hmm:

anyone else who runs a 420a care to chime in to help :)
 
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Well, here's some photos. I even found some marks from the person that put the motor together and they line up (last photo) and apparently it ran and drove before trying to go stand alone.
 
What about ignitors? I'm trying to run off of 2 channels off of a 4 channel AEM ignitor. I have the wires ran to the other 2, but just capped off in the harness with shrink wrap just incase they want to upgrade to COP in the future. What ignitors do other people run?

I also did some future proofing by running the LED fuel wires from the mainboard in case they decide to run secondary injectors later on. The ones going to the current injectors in the car are from the expansion board because full sequential was my personal goal at first, now I just want it to run. Does DIYautotune allow you to mail it back to them and let them make sure the computer is still good and set up properly for this set up?
 
Why are you using an aem ignitor? Years ago I ran a dsm ignitor but that was with an MS1. Everyone now uses the drivers in the Megasquirt to run the coil. Especially with a MS3 unit. The ignitor should still work but you are adding additional components to the system that aren't necessary.
 
On a side note, is there an oil line going to the turbo? I only see water lines? Also, I think i spy a FMU to the left side of the intake manifold. That will not be needed with MS.
 
The turbo is oil-less. Customer read that they're shiznit, but I don't believe it and wouldn't run one myself. I had some back and forth with DIYautotune before we ordered the computer and they suggested an ignitor, we already had the AEM one on the car and they said it would work fine. So I should be able to bypass the ignitor and not burn up the MS or coil?

Yeah...it has the FMU plumbed after the boost referenced one. I have no idea what they were thinking there and I don't want it there anymore, but the customer believes in it so it's still there. The pressure is steady so I don't think it would cause the problem, but if you guys think it would I can take it off, maybe, it is hard to get my hands because that giant intake. I don't know what brand the boost referenced one is anyways so I don't know if it's a reliable one or a Chinese knock off.
 
If the MS is built properly you shouldn't have any issues connecting the coil straight to the ECU, I would open it up and take a peak inside to make sure everything looks correct before making the switch. Per my last email, the crank sensor is inverted. Work on fixing that before anything else.

I would ditch the FMU, it will be screwing with you in boost when it jacks the fuel pressure up with boost. At a minimum I would have the vacuum line disconnected from it so it has no impact on your fuel pressure.
 
Well, I got in this morning and opened the computer up and moved the J1 jumper around. In the 1-2 slot it doesn't show anything in the logger. 3-4 is where it was at before. In the 5-6 slot with Falling Edge I have less sync losses, but they're still there. Rising edge is full of sync losses. Still no start, sounds a lot better though. Any other ideas?
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IT RUNS!!! I took out the new crank sensor I put in hoping to find metal or something that could be throwing off the readings. There was nothing on it except for oil. I threw the old sensor back in it to try and it fired right up. Idling a bit rough and missing, but no problems starting now at all. J1 jumper still on 5-6 with falling edge.
 
Crank sensor looks correct now. Glad you got it running. I can shoot you my IAC settings if you want to use them for reference.
 
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