Noob frustrations; car starts, but won't keep running

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protege5
MS/Extra Newbie
Posts: 5
Joined: Sun Jun 25, 2017 2:22 pm

Noob frustrations; car starts, but won't keep running

Post by protege5 »

I have assembled and installed an MS1 V3 with two coil drivers, and no idle control. Everything's wired up, and the car starts and runs occasionally, but the more I tweak things, the worse it runs. I've tried reverting back to a blank slate, and that didn't help much. I'm really at a loss. I've tried doing research and reading everything I can get my hands on, but I'm honestly not sure what I need to learn; there's so much, and a lot of what I'm reading doesn't seem to apply to me.
What I know:
  • When the engine dies, and when I'm trying cranking the engine and it's not starting, TunerStudio gets disconnected. Is this normal? Or is the MS shutting off, causing the engine to die/not start?
  • I have a dash-mounted Air/Fuel Ratio gauge of unknown accuracy. Whenever the engine's running poorly, it shows very lean, even though TunerStudio shows that everything is fine. Both are connected to the same heated narrowband oxygen sensor.
  • This car is an older build that used to have a Haltech ECU that died. I purchased the car in non-running condition, and installed the Megasquirt to get it running. All of the sensors are working (although the air temperature sensor is off; it shows that the air temp is about 40 degrees when it's actually in the 80s, but I figured that shouldn't prevent it from starting, so I'd fix that later.) Otherwise, I've gotten all of the existing sensors working correctly. Spark is sent out through an MSD DIS-2 Plus, then to an MSD coil pack in wasted spark setup.
  • Car is an '02 Protege5 with the 2.0L I-4, forged internals, turbo. Has alcohol injection that I haven't even looked at yet, and will worry about later; the tank has been drained, so I know it's not interfering with anything.
  • Car has 42 lb high-impedance injectors; set to 7.6ms flow.
  • I know I have good ground on all 6 ground pins.
  • When it does start, it smokes black smoke for a while, while the dashmounted AFR gauge shows 'Stoich'.
  • It backfires a lot.
Where do I start to try and figure this out? I keep reading to 'check the logs', but the only log I can find in TunerStudio is the crankshafter sensor log, which doesn't seem particularly helpful from what I can tell.
Thank you in advance for any help you can provide.
Protege5.msq
protege5
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Posts: 5
Joined: Sun Jun 25, 2017 2:22 pm

Re: Noob frustrations; car starts, but won't keep running

Post by protege5 »

A couple more things to add, which I forgot to mention; if I can get it to start, and rev it above 2,000 RPM, it runs smooth and sounds quite nice up to about 5,500 RPM, though it accelerates slowly, as if it doesn't have a lot of power. The dash gauge shows rich when decelerating, and lean the rest of the time. If I try to increase the percentages in the fuel map, it loses power and dies. As long as I keep it above 2,000 RPM, it runs fine and tunerstudio stays connected. If I drop below 2,000 RPM, it coughs, backfires, and dies. Getting it to start and run above 2,000 RPM is difficult, and only happens about one out of every 20 attempts, at most; usually, it just catches, and immediately dies.
Another thing I forgot to mention is that I bypassed the idle air flow system with a small hose. A week or so ago, it was idling fine with that in place, and would start easily, but I'm not sure what I've done that's changed that; is just ran fine back then, and doesn't run fine now. The only changes I've made since have been to fix the oxygen sensor (it was grounding out due to a wiring mistake from the previous guy), and add the air intake temperature sensor. I've made changes to the fuel & spark maps, but have reverted to the version that worked back then, yet doesn't work now. I've also made changes to the startup enrichment settings, which seemed to help somewhat (at least the dash gauge shows that it's not lean 100% of the time during startup), but those changes were made after this hard-to-start problem began.
protege5
MS/Extra Newbie
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Joined: Sun Jun 25, 2017 2:22 pm

Re: Noob frustrations; car starts, but won't keep running

Post by protege5 »

I've figured out a big part of it by myself; the fuel pump wasn't being run long enough, resulting in insufficient fuel pressure. I jumped the fuel pump relay, and the car now runs just fine without dying, and is ready to be tuned. I haven't yet taken the time to find out if the fuel pump run time can be configured, but at least I now know what's wrong, after scratching my head over this for the past month. Hopefully this info helps someone else.
That having been said, here's an attached log from running my car, showing the bogging when I try to accelerate. I probably just need to start the basic tune; hopefully I've figured out the big part of the problem.
2017-07-23_23.53.17.msl
DaveEFI
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Location: SW London, UK

Re: Noob frustrations; car starts, but won't keep running

Post by DaveEFI »

First thing I'd do before anything else is fit a wideband O2 sensor system. Without that, you're tuning blind.
Rover SD1 3.5 EFI
MS2 V3
EDIS
Tech Edge O2
London UK.
whittlebeast
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Re: Noob frustrations; car starts, but won't keep running

Post by whittlebeast »

You have WAY too much Acceleration Enrichment. You have Voltage dropout. You need to get AFR into the log.

Andy
protege5
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Joined: Sun Jun 25, 2017 2:22 pm

Re: Noob frustrations; car starts, but won't keep running

Post by protege5 »

In the month since I started this thread, I've made a lot of changes to my tune. Here are the current tune and a recent log.
Protege5.msq
2017-07-25_00.26.12.msl
I've adjusted the acceleration enrichment down, but I don't really know what the numbers should be. I haven't been able to find any sort of "what to expect" for a lot of the numbers in the tune. I was told at one point that it needed to go 'way up.' Hoepfully I've taken it down a reasonable amount; without the car running long enough to idle, it's hard to figure out.
My previous post about the fuel pump was wrong. The actual situation is that the engine warmed up to closed loop mode about the same time I jumpered the relay, so they simply happened at the same time.
The real problem is that the car will fire, but not catch and run until it's warmed up to closed loop. I've played with the ASE & the cranking pulse, but I'm still having no luck getting it to start, untl the engine is warm. If I crank it long enough that the engine warms up, then it will start, idle and run. Until that time, it just fires, but never starts.
BlackBird_SR71
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Re: Noob frustrations; car starts, but won't keep running

Post by BlackBird_SR71 »

Your Warm Up enrichments ( Cold start ) are a mess. No wonder it doesn't want to run until fully warmed up. Warm Up and After Start enrichments are not the same thing.

You have your O2 sensor set to Narrow Band, which I doubt is what you are running. What is the exact model of your WB.

You can't tune with sensor uncalibrated. You mentioned IAT sensor was reading 40 F when it was actually 80 F out. Has that been fixed?

Band-Aid fixes like bypassing the Idle Air Control with a hose are not a good idea.

Really, this Tune is a mess. I like trying to help people out, so I'll send you a PM with my contact info. Lets see if you can get you up and running with a better baseline .msq.
protege5
MS/Extra Newbie
Posts: 5
Joined: Sun Jun 25, 2017 2:22 pm

Re: Noob frustrations; car starts, but won't keep running

Post by protege5 »

Its taken me a while to get this far, but I figured now would be a good time to update this for any who struggle with similar things.
The problem I had getting the car to run correctly was not related to the MS at all; I had a defective coil. It was putting weak spark out on 3 of the plugs; the whole car was just running on cylinder 2. Once I replaced the coil and wires, the car runs great, and I'm now starting to get it tuned, after calibrating the IAT. Thanks for all the advice, hopefully I can return the favor to someone else who's struggling with MS1.
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