So i'm driving along and everything was great. I pull into the garage and install an electronic boost controller....start the car up and get a reset or two...try to drive and I get more. Then they stopped and became very spread out, but still sporatic.
Then they started getting worse and worse...now it resets at idle every few seconds.
Since then, I have since removed teh boost controller and tested this MS in another car with an identical setup. The MS is fine.
The plug wires are new as is the coilpack.
SPECS:
MS1 runnign 29q2 (tried other codes, still resets)
Wheel decoder
3 VB921s driving a new coilpack
The only thing I know is that it got worse over a period of a few hours to totally make the car undrivable. All the grounds are great and the setup was working fine for a long time. This just started outta nowhere. Ideas? Things to check?
Another Reset Thread
Moderators: jsmcortina, muythaibxr
OH...yeah...tried that too 
I wish I had access to a scope. I'm currently looking to buy one though.
As for a wiring diagram...not sure what your saying. I have the VB921 mounted to the MS case lid, but running Pin3 ground direct to the engine block where it has been. Checkd all the coilpack wiring and its fine too.
I wish I had access to a scope. I'm currently looking to buy one though.
As for a wiring diagram...not sure what your saying. I have the VB921 mounted to the MS case lid, but running Pin3 ground direct to the engine block where it has been. Checkd all the coilpack wiring and its fine too.
What does that mean?OH...yeah...try that
So, you tried that and there was no difference?
I assume all the wiring is fine, since it worked. But something must have changed. Could be loose wiring connection etc. I also assume you have already tried looking for the obvious like loose wires etc. Disconnect anything you installed recently etc.
Maybe you can borrow a scope?
How about a DMM?
Wiring diagram? Take one of the diagrams from megasquirt and modify it to the way you have it wired, and include the wiring of the +12 V source. How exactly is it wired. Number of grounds and everything so I can ask you to make some measurements on the scope.
For a start make a measurement of the ground inside the MS with the ground of the scope on the car chassis. I assume the scope has at least a 100Mhz bandwidth.
Next measure the +12 Volts where you get the voltage on the car, and then inside the MS with a scope.
Thanks for the fast replies...I currently don't have access to a scope.
As for wiring, I chopped off the oem connectors for the ECU and soldered directly to the DB37 as it makes for a very clean install since the oem ECU is gone.
The power comes from the same line that fed the oem computer, dedicated, nothing sharing it.
As for grounds, there are 18g wires that go to the oem computer ground wires in the harness and a 4th one that goes to a bolt on the chassis.
I do have a DMM, and from what I could see (d*** those things and their averaging) everything is normal.
As for wiring, I chopped off the oem connectors for the ECU and soldered directly to the DB37 as it makes for a very clean install since the oem ECU is gone.
The power comes from the same line that fed the oem computer, dedicated, nothing sharing it.
As for grounds, there are 18g wires that go to the oem computer ground wires in the harness and a 4th one that goes to a bolt on the chassis.
I do have a DMM, and from what I could see (d*** those things and their averaging) everything is normal.
Can you try to run the ignition without the 3 VB921s. I'm thinking you have to run a test that determines if the ignition is the source of the problem.
Maybe go back to the original ignition if possible. Or try to ground the MS case. With the engine running, see if there is any voltage on the case of the MS. You might measure less than a volt.
Some of the existing threads suggest resitance plugs, are you using those?
Can you think of any other changes you have made recently. Where the 'new' coil packs installed recently?
Maybe go back to the original ignition if possible. Or try to ground the MS case. With the engine running, see if there is any voltage on the case of the MS. You might measure less than a volt.
Some of the existing threads suggest resitance plugs, are you using those?
Can you think of any other changes you have made recently. Where the 'new' coil packs installed recently?
going back to stock ignition would be a long process and a worst case scenario. The packs are new, but the car was running good after the new packs were installed. I'll check the stuff on teh case, but that'll have to wait till tomorrow.
Remember, this MS works perfect in another car with the same setup.
Remember, this MS works perfect in another car with the same setup.
I had mine wired exactly like that and MS reset over and over, along with enjoying the classic "click" from the fuel pump relay turning on and off. I ran all the grounds to one spot (and bypassed the stock ECU wiring for earth) and the reset problem was solved.
I dont suggest using the stock ecu's earth wires.
I dont suggest using the stock ecu's earth wires.
94 Mazda MX-3 V6: MS'n'S, 550cc injectors, 395 whp 397 ft lbs @ 15 psi boost
