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Old 11-13-2008, 04:02 AM   #1
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Default Won't Start! (better than before)

So I go the car to stumble to life earlier, but unfortunately did not log the attempt. ('00 with MS1, 97cas, stock injectors). Went to start the car, had it fire and then die, then started again manipulating the throttle. When it started again it hated life, pegged the AEM at 10 (lowest it would go) and ran HELLA rich. For some reason TPS, Coolant, and IATs are not logging (or showing up in megatune). I also discovered that I need to do the Tach driver circut, but I am not sure which pin on the ecu to pull the tach signal from. R43 need to be installed? I would think not.

Tach circut:
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Old 11-13-2008, 09:43 AM   #2
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You do not need R43, or Q16 or R57 either. That circuit is for driving an old-fashioned ignition coil (with a distributor) directly, whereas your coils have on-board igniters.


No TPS, CLT, or IAT sounds like a grounding problem to me. On the '00, these sensors (as well as a couple of others) all go to ground through the ECU in the stock configuration, rather than through a direct ground wire as in the earlier cars (this was done to improve sensor accuracy.) If you've removed the ECU, then you need to provide a path to ground for them, or they won't work. Specifically, locate the black/red wire at position 3F of the ECU harness. This is the sensor ground. You will need to connect this wire to one of the MS's ground terminals on the DB37.


I'm afraid I can't tell you with absolute certainty which wire feeds your tach, but I can make an educated guess. Judging by the factory wiring diagram, I believe it is most likely the green / orange wire at pin 2K of the ECU. I say this because that pin goes to the instrument cluster, the A/T controller, and the under-hood diag box at a position marked IG-.
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Old 11-13-2008, 01:56 PM   #3
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Thanks, I would have never guessed the grounding problem. As for the tach, I believe I already have the correct wire run from the MS to the harness, but never built the tach driver circuit for some reason.

Also for the tach circuit, where is a good place to pull 12volt ignition, and which pin do I use on the ECU?
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Old 11-14-2008, 02:31 AM   #4
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Quote:
Originally Posted by coastertrav View Post

Also for the tach circuit, where is a good place to pull 12volt ignition, and which pin do I use on the ECU?
Anyone?

Also I do not have a 2N2222A transistor, would the PN2222AD26ZCT that comes in the relay control modkit work? If not what else could I substitute it for?

And I ran 3F to ground like you said Joe, and voila! coolant, IAT, and TPS all there, but now RPM has dropped. I think this is due to not having enough battery power to crank the motor over fast enough (I'm guessing), and I think it is probably trying to crank in the sub 150rpm range. I can smell fuel, but because of not having an RPM reading there is no ignition I suppose, and the fuel is just the priming pulse.

Last edited by coastertrav; 11-14-2008 at 04:20 AM.
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Old 11-14-2008, 09:56 AM   #5
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Yeah, the PN2222AD26ZCT will work just fine. Semiconductors (both discrete and IC) are funny when it comes to naming conventions. Transistors seem particularly subject to this, as well as things like 74 series basic logic ICs.

For any given device type, there are typically dozens of different part number, mostly referring to variations in speed rating, temperature rating, package type, and so on. While certain of these can be significant (a surface-mount IC vs. a through-hole part, for instance) they are for the most part interchangeable. So long as the root of the name (in this case, N2222) is the same, and the part physically fits, it'll work.

I'd take +12 from the white/red wire that is your primary switched +12 feed to the ECU. This goes for all years.

And yeah, things can get funky when you've got the battery depleted from multiple starting attempts. Charge that sucker up.
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Old 11-14-2008, 12:54 PM   #6
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Thanks man, I appreciate all your help.
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Old 11-16-2008, 05:40 PM   #7
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So, I charged up the battery, and things are still a bit funky. For some reason I no longer have a rpm reading since adding that ground...

Here is my latest log from starting.
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