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Super Rich Idle After MS Install

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Old Mar 25, 2007 | 09:16 PM
  #1  
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Default Super Rich Idle After MS Install

Now that I have MS installed but i have it setup so I can switch between MS and the stock ECU I can't seem to figure out why it idles so rich running on the stock ECU.
My WB is reading 10.0 which is as rich as it will read, if I give it gas it goes up to 12 and right back to 10.
I reset the ECU by pulling the neg battery terminal and letting it sit for 10 minutes then holding the brake for like 15 seconds to discharge any other power in the system. This didn't fix anything.
I checked all vacuum leaks, that's not the problem.
When starting it i have to turn it over once, it'll start and jump up to like 1200 rpm, run a second then die. THen i can try and start it again and give it a bit of gas, then it will run idle again once i let off the pedal.

I'm not expecting people to troubleshoot what i've done, but is there anything that someone could think of causing this?
Old Mar 25, 2007 | 10:39 PM
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well if you messed up some wiring obviously. Let me ask a few questions to point you where I would look first.
1. So your WB02 is reading rich and your car is acting accordingly shitty right?
2. Do you have a proper narrowband signal going into the stock ecu (Narrowband sensor or LC1 simulated)?
3. Have you checked your wiring for shorts? In particular you might want to look at the wiring for the o2 sensor, AFM, throttle body, and fuel injector outputs.

Electronics can be a bitch eh? In all honesty, it sounds more like a vaccum leak than anything else so double check that stuff. Make sure your vac line to MS is hooked up and go over everything again.
Old Mar 25, 2007 | 10:41 PM
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Yeah after completing the install and having this problem i want to kill myself. Had i the chance to do it again, i'd have used boomslang connectors.
Old Mar 25, 2007 | 10:50 PM
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coulda woulda shoulda, I bit the bullet and bought a female so i can physically swap the ecus with no mixing options. too complex that way for me.

btw you got a pm.
Old Mar 26, 2007 | 11:57 AM
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How do you have it setup to switch between the stock and MS ECU's?
Old Mar 26, 2007 | 03:31 PM
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Are you sharing the stock coolant temp sensor? My guess would be that you didn't remove the bias resistors in the MS which is causing the stock ecu to think the engine is colder than it really is. You will probably also notice your fan doesn't kick on till around 250 degrees.

If you are sharing the sensor remove the bias resistors in the MS, use easy therm with your stock ecu bias resistance (I posted on how to find that a while back), and you'll be good to go from there.
Old Mar 26, 2007 | 03:37 PM
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I did remove the bias resistors and attempted to reflash with Easytherm. Something didn't work right with that though.

I just removed the entire MS system from the car. Hooked everything back up and the car still runs rich. I'm disconnecting the wideband from the ECU 12v and grounds cause I think that might be giving me a messed up reading but i'm not sure about that.
Also, when starting it I now have to turn it over once. Then try again and give it a little gas to get it to idle. The first time i turn it over it will run for a second and die.
What the hell did I do? I guess i need to check all my wiring again because maybe one of my crimps is messed up. I'll check that tonight.
Old Mar 26, 2007 | 03:47 PM
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Did you get the injector wiring put back right? MS is batch fire and stock is wired as Sequential.
Old Mar 26, 2007 | 03:50 PM
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Yep, that's all correct.
Old Mar 26, 2007 | 03:51 PM
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Maybe one of the vampire clips i used F'd up a sensor wire. Right now that's what i'm thinking.
Old Mar 26, 2007 | 08:01 PM
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Fixed the problem tonight.
Spend an hour repairing previously destroyed damaged wires that had been electrical taped up. I removed all that can be described as being a "the worst wiring ever" and then resoldered everything back together.
That's what I get for buying someone elses project.
I pretty much brought the harness back to stock form now and will be building a pnp harness from the boomslang connector i ordered today.
I've made up my mind to never modify a stock harness unless there are no other options.
In short. Spend the $30 to get the female boomslang connector. $20 for the part $10 to ship.
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