BBR's 83GT - 552 BBF version 3.0 (at least)

[BlueCuda340]

Is it grounded directly to the battery? I had small processor resets causing my datalogs to be all crazy(contstanly starting over) but the car ran fine. Scott Clark suggested that I move the ground for the MS directly to the battery. When I rebooted some things to turn on the fuel control side of things I did just that. I took my wideband and MS3 and grounded them together on a dedicated run to the battery. Now my datalogs are as they should be. This also took care of a wierd issue I had at startup where it would sometimes backfire before it started.

[BBR]

This also took care of a wierd issue I had at startup where it would sometimes backfire before it started.

Yep. I've had that a couple of times. Kaaaaa-Pooooowwwwwwww!!!

[BlueCuda340]

Yeah its real fun in the staging lanes LOL

[Beagle]

What does "reset" mean, like it's rebooting? Maybe look into a voltage regulator / conditioner or build a battery pack for the MS part of it?

[BBR]

A reset is just any condition in which power is interrupted to the processor. Can be caused by a multitude of reasons. Grounds are a common issue, sketchy usb-serial converter, noisy 12v source, etc.

One of the things I am going to look at is when I had this MS in the Ranger, it was mounted vertically and I had to put a square of dense foam in it to keep the prom from falling out. It no longer has that foam in it so am going to see if it is loose or prone to vibration issues.

It runs great when it is running. The resets do not begin until after it has been running for a little while so it's not something that is present 100% of the time.

I'm going to improve the grounds, pull the MS and give it a good once over.

[milner351]

you're starting to convince me to get the MS built by them.....

I now have a twisted wedge EFI / 5.0 style intake, and a more carburetor like intake (looks like a victor knock off) with injector bungs for SBF.
I keep going back and forth between the ready to run 5.0 set up (easy, but more expensive) or doing the bangshifty method of building my own MS1,2, or 3.... (more work, allot less money). Either way I think using as much of the factory EFI wiring and sensors is smart?

[squirrel]

building electronics is easy...this is the TV we built in 1973, it was still working when I made the video in 2008.

https://www.youtube.com/watch?v=056xOJcrbsg

[BBR]

The build is easy. No need to worry about it. I would use as much of the factor wiring as I could. That is essentially what I did with the Ranger. I use an MS to EEC adapter board, kind of the precursor to the MSPnP stuff.

I really think the issue I am having is either ground of 12v noise related. I was reading about noisy 12v reset stuff and Matt Cramer commented in that thread about how crazy noisy the guy's power source was. I looked at his datalog and mine is as bad or worse.

I am going to run power to the MS directly from the battery and change up the grounds to see if that does not clean it up significantly.

[squirrel]

sounds like a good place to start. Also check wire routing, make sure there is nothing that might have a large field around it, near any of the wires that connect to the computer. Such as secondary ignition wires, etc. And make sure the wires to the coil pack are kind of physically isolated from the the sensor wires.

[CDMBill]

Welcome to the really fun part of EFI. Isolating grounds and and getting clean power is the best part. Coil grounds have to go directly by to the heads. I isolate 12+ with relay off battery. All the other EFI grounds are are also common to a ground bus back to battery (-) I use four wire Cherry sensor which has ground drain from shielding. 10 years of fun and now I get it.

[CDMBill]

Oh, and yes I know this isn't your first rodeo with this stuff, but i've had this beaten into my head by some of the best.

[BBR]

This thing is interesting. I can crank it up, and it will run for about 3 minutes, varying rpm then holding it steady at 3000, then the tach bounces and it just shuts off like you turned the key off. Boom. Then it absolutely does not want to restart. I logged it again and SecL does not reset until the rpm goes wonky. BattV is a bit odd in that it starts out real nice and gets progressively more noisy. MS 12v is currently pulled from the battery cutoff. I am going to change that so it gets it directly from the battery post. MS and coils are grounded to the same spot on the block, but I just realized I do not have a block to body ground on the engine. It is just grounded through the motor plate, etc. Adding one may not fix it, but it certainly won't hurt.

I adjusted the hall sensor to narrow the gap in the event it was getting a weak signal. May change this from using an MS supplied 5v, to a 12v source.

I pulled the MS and gave the board a good once over. There were a couple of spots that needed attention. The two transistors for the Efi that are heat sinked to the case both had issues. One had one leg almost touching the center and the other 's legs were almost grounded to the case. I feex.

[squirrel]

post pictures of all the wiring under the hood....let's see what you have....it's not easy to see stuff without pictures!

[squirrel]

this is the picture you posted of the setup...

[BBR]

First I'm going to post a pic of the datalog.

First dip in battv (blue) is when I turned the electric fan on. It typically stays on all the time. Battv stays relatively stable, increasing with rpm, then it starts to get REALLY noisy. Starting to think maybe the 1-wire alternator's regulator is going bad or it is just mega-noisy by nature. SecL (green) continues to count up correctly and only resets right at the point the engine dies. Of note is the fact throttle position (white) continues to climb even though there is no TPS installed.

I'm going to post the msq and msl to the MS forum and see what those guys have to say.