MSefi.com read only forum (Jan.15,2018)

Hi all,

I'm still working on getting MS running my car. I have new 550 cc injectors. I used the calculator to get a req fuel of 6.1 and set -40 pulse width to 5.4 and 170 to 1.2

When I check plugs they are wet. Does it make sense that these values are still to high? Is there something else I should be looking at? I am getting spark and the timing is set right. After letting the engine sit and cranking it with injectors unplugged it will fire but can not run as no more fuel is being squirted.

Volvo B20 F engine.
2 liter
4 cylinder 4 injectors each at 550 cc/min

MS 1 v2.2 board. Flyback board.

Many thanks,

John

http://www.volvo1800r.com

I'd try backing the values off some more - the recommendations are just a ballpark figure and some cars may need less.

Ok, looks like a bigger problem than I thought.

When I turn the key from the off to the run position so the primer charge goes I get about an ounce of fuel out of the injectors maybe even more. My priming pulse is set at 1.0. It seems to me that the injector stayed on for 1 second, not one millisecond.

Thanks.

Forgot to mention that when i turn to the run position I also see my Tach on the laptop go to 1400 rpm. I don't remember that happening when I hard the car running a few years ago.

I haven't had a chance to get back to the car and look at it again but I'm thinking that maybe the injectors are just constantly getting current and staying open. So maybe the deluge of gas was just due to the Fuel pump priming the system. Maybe I blew something on the relay board or in the MS board.

Do the injector LEDs stay stuck on if you test the MS on a Stim?

I had my MS built by RS Autosport and did not buy a Stim. Looks like I may need to do that now to diagnose the problem. The injector led on the MS box does not stay lit.

The injector LED is not connected to the injector drivers and goes out when you stop seeing RPM.

I looked at the car again for a min. With the relay board plugged into the MS unit the injectors are getting a constant 11.xx volts. If I disconnect the MS unit but leave the relay board with power the injectors get nothing. It seems like a hardware issue to me. What could the Stim tell me? I'm thinking I'll just send it out to have it repaired, I'm not that comfortable soldering circuit boards.

and thanks again for all the advice.

I'd make sure the relay board injector power terminals have 12 volts with the MS disconnected first, in this case. The Stim will tell you if the MS's injector drivers are working correctly.

Relay board does have correct power. I'm going to order a stim from you at DIY today. Assuming I blew out my injector drivers how do I track down where the problem is?

using a small led probe, place in the circuit instead of an injector, turn the key on and see if the led stays on.

The drivers are at the top of the board on the heatsink rail. I beleive they are Q1,Q5.