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

Before I go crazy and or admit defeat I thought I would ask the group for assistance. I recently completed an installation in a 1980 Porsche 911SC of an MS2 daughter board with IAC and MAP daddy sensors. It is on a V3 board and I'm not using ignition control. I installed a new wiring harness with all the extra wires. It was running on MS1 using fuel only with custom firmware. I successfully downloaded and installed MS2 version 2.905. I'm also using an MSD6AL with the tach input to MS2 on pin 24 from the tach adpter as I had used on MS1 since I am not using MS2 for ignition control. It will not start and is as if it isn't getting fuel. The fuel pump runs appropriately. The injectors are high impediance as I was using before. Most of the settings including an interpolated VE table imported from the MS1 tune. The MAP sensor reading and IAT sensor readings appear correct, but the tem sensor reading is acting like it is at full operting temperature. It is a GM typed that worked perfectly with MS1. It also has an LC-1 wide band O2 sensor also carried over from the MS1 install.

Any suggestions would be greatly appreciated.

I'm going to track down the incorrect reading from the coolant temp sensor. I know it can be a problem. Writing all this down helps.

Any further thoughts, please let me know.

Thanks.

Randy Hoch

Do you get a coolant temperature sensor reading on the Stim?

Thanks for reply. I do not have the stim yet. I did however find a bad connection on the return wire for the coolant sensor.

I'm sure you know, but if the coolant is reading above about 70C on MS it won't enrich the mixture for a cold start.

I've also got a feeling that the defaults are for low impedance injectors (to avoid damage to the drivers).

Thanks for the reply. I do know it won't enrich it enough if the coolant reads too high. That is why I mentioned I found that problem. I have not had time yet to fix. I will also check the injector settings. Thanks again.

Ok. The coolant temperature is now reading and the injector settings are correct. I still will not start. Where to now?

Thanks for your help.

Randy Hoch

arhoch wrote:Ok. The coolant temperature is now reading and the injector settings are correct. I still will not start. Where to now?

Thanks for your help.

Randy Hoch

Please post a copy of your MSQ and a data log of an attempted start.

Ok. It willl be a few day before I have a chance to get back to the project.

Randy Hoch

Matt,

Attached are what should be the data log from an attempted stars and th msq file.

Thanks.

Randy Hoch

That log doesn't appear to show the engine cranking. I know this may be confusing, but the data log starts after you save the file.

Ok. To make sure I'm clear, I should start data logging, save the file and then try to start it.

Matt,

Try this date log.

Battery voltage drops, but you're not getting an RPM signal. How is your RPM input set up?

It is coming in from the msd tach adapter to pin 24 as it was set up for the ms1. The v3 bord is wired per the Hall/optical input circuit.

That should work fine. Do you get an RPM signal on the Stim?

Also, try a tach signal masking % of 10% instead of 50%.

Changing the tach signal masking didn't help. I do not have a stim since I didn't build the board. The only changes since running on MS1, have been the addition of jumpers for IAC and the MAP daddy dual barometric sensor. It is possible that I have wired it incorrectly, or the new harness has a problem. I have the tach input connected to the white wire of the twisted pair in the harness. Is that correct?

I've seen lots of pro made looms, and they all seem to use different wiring colours. Did you get a diagram with yours? If not I'd check the continuity of your tach feed to pin 24.

Thanks for the idea. I have a wiring diagram for the harness, the wires are marked, and I have continuity from the engine compartment all the way to the 37 pin connector.

All,

Thanks so much for your help and input. While it still will not start, I need to close this post out as resolved. I will continue to trouble shoot the no tach signal until the problem is found. At this point, it may be either in the daughter board or inthe MSD/tach adapter. When I figure it out, I will post a final resolution.

Thanks again for all of your ideas and input.

Randy Hoch