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

I have the MS II running the 2.89 on an AMC 258 with a GM TBI system and GM IAT and CLT sensors I bought from DIY. I got my system all wired up, but it will only start and run if I manually prime it up with gas by squirting gas into the tbi for a bit until the engine warms up a bit and it will idle on its own. In order to start it we had to set the timing very high, which means the motor is very responsive but dies under load. The CLT and IAT sensors are giving very high readings when I input either the default GM sensor calibration values from MS or if I manually enter the values that MS gives for its sensors on the DIY website. I made sure to input the values in degrees F and enter the 2490 ohm value as well. I checked the resistors on the ECU and R4 and R7 are reading 2.49. I'm assuming from reading the manuals that this is causing my cold start problems and could be effecting other things as well. When the motor is warmed up and idlling in the garage it sounds loud and strong, hits quickly, and the injectors appear to be firing well. On a side note, I have never gotten the MAP sensor to give out a reading. I suck/blow on it, connect it to the TBI, still no change on my laptop's Tuner Studio screen. Any ideas? I'm flumuxed here. I recieved a faulty cable from DIY (loose connection) and ended up chopping the cable up and soldering on the wires that connect the ECU and fuse relay box in order to make a better fit. After I did that, the intermittent short that was cutting power to the pump and ECU disappeared and it would at least start and idle on a warm day with a little fuel poured down the TBI. Now that it is cold out, it is much harder to start but idles ok once warm. Any Ideas?

In Megastim I can't get the IAT or CLT readings to change. So this means I have a problem with my board I guess. I should have just bought the dam unit assembled instead of putting it together myself. I had an easier time rebuilding my jeep from the ground up and fabricating parts for it then trying to troubleshoot all of the electronics.

Well, CLT and IAT problems solved. I somehow forgot to connect R5 and R8 to the board when I put it together last year. The Megastim saved me again. Now to figure out why the MAP doesn't work.

And I had the MAP in backwards. Ok. Lets try this now.

hoffmanuno76 wrote:In Megastim I can't get the IAT or CLT readings to change. So this means I have a problem with my board I guess. I should have just bought the dam unit assembled instead of putting it together myself. I had an easier time rebuilding my jeep from the ground up and fabricating parts for it then trying to troubleshoot all of the electronics.

The next one will be easier.

Was re-building your Jeep the first thing you ever did - or did you practice on something easier first, like perhaps your bike when a kid?

But now you've found the faults on your MS it will be easier to find any in the future (if they might happen). Imagine try to do that if you hadn't built it?