1977 280z w/ MSII, rough idle, sneezes, and wont accelerate

[ZDrummerGuy]

Hello, my baby is having trouble idling and accelerating. I just recently installed MS2 in her so I could surpass the issues I was having with the electrics. However, the problems I was having before are almost the same as the problems now. A very rough idle and no acceleration in the rpm.

I have replaced the coil, distributor, plugs, plug wires, fuel filter, ECU (to MS2), and the fuel regulator. I hooked the distributor up to my laptop and the board and spun it around with a drill and got rpm on the screen, so I think that works. The coil is working too because cranking it over unhooked give plenty of spark. I did a check on the fuel pressure after the fuel filter and got 37psi with the ignition on (the pump wont shut off when the car is on on, not start.. Maybe some feedback with this too please? I know it needs to be linked to the MSII board) while cranking it over I received 34-35psi so I ruled fuel pressure out... I know the plugs get spark because after the initial cranking the car will run for 30 seconds perfectly (from the CSV) then start to idle rough then die. That is, IF the car starts. Sometimes it just cranks over and doesn't start.. instead what happens is a big sneeze and puff of white smoke pours from the intake, along with some oil from the PCV system.

Another thing that isn't up to shape is the tach, which doesn't work anymore... which I think should be hooked up to the negative side of the coil but has decided that it doesn't like the new coil or the new EFI system...

I have many issues... Maybe an enthusiast who knows their way around these systems can lend a helpful hand! Thanks!

[madkaw]

I have MS3 on my Z. Don't have time right now to help- if I can, but you should be posting on Hybridz if you haven't already

[Zed Head]

I notice that you haven't mentioned your fuel map at all. Makes me think that you may not understand exactly how Megasquirt works. It doesn't adjust itself, you have to give it the right starting point, then tune it from there. It takes quite a bit of work to get it tuned right.

Have you been on the DIY site? Spend some time here - https://www.diyautotune.com/faq/faq.htm

[siteunseen]

The MS II didn't fix the problems you had in the beginning? You've replaced a lot of stuff and it hasn't helped, I did that too.

For mine the biggest thing was a huge rotted hole under the intake at the back, windshield, where the EGR is. Get a mirror and look under there.

The 2nd thing was putting a potentiometer in the coolant temp sensor circuit.

http://atlanticz.ca/zclub/techtips/tempsensorpot/index.html

[ZDrummerGuy]

Ive adjusted my VE, Spark Advance and my AFR tables. I know the basics but I ain't no expert haha. Ive been through TunerStudio top to bottom and then researched everywhere. Twice. I'll keep tuning though! Thanks!

[ZDrummerGuy]

Yeah, I really just wanted to get rid of the old EFI system. I was hoping the new system would help get rid of the original problems I was having... but that clearly worked out well. Another thing to mention is most of those parts were bought and installed before I installed MS2. So I got no where with the old system. But thank you for the input! I will check for holes near the EGR and Ill check the Coolant Temp Sensor with my potentiometer.