Post by
GilgaNess »
https://forums.nicoclub.com/gilganess-u304511.html
Thu May 26, 2022 4:27 pm
Ok the back story, so this has been an evolving problem for me. My Z31 Turbo was running (although running rich and blowing blue smoke likely due to turbo) but it ran. I changed the valve cover gaskets because of oil leak. In doing so I removed the intake plenum, distributor, and throttle body. I replaced the intake plenum with a new gasket, replaced the TB with a new gasket and replaced the distributor with a new CAS, rotor and cap. I also replaced spark plugs & wires as well as ignition coil.
I also needed to replace the fuel pump. I dropped the tank and discovered that the evap port on the tank was corroded and had a hole. I ended up installing a new fuel tank along with the new pump. I also replaced the fuel filter as well as the FPR.
After this I tried starting the car and it wouldn't turn over. I discovered that I didn't know anything about ignition timing. I created a thread here and ended up resolving the starting issue.
When I first started the car up the idle was very high [3k rpm) and there was a very loud whistle. I adjusted the throttle cable because the bolt had moved and was putting too much tension on the throttle. I started the car again and the idle was initially ok but the loud whistle remained (this did not exist before all of the work) then the car slowly started bogging down and stalling. After several attempts the car now turns over but stalls immediately!
Here is what I've done regarding this issue so far. First I suspected a large vacuum leak, I attached a smoke machine to the brake booster and found a crack in my intercooler piping. I replaced that section of piping but this made no difference. I reattached the smoke and found no other leaks and I checked that all vacuum lines are connected. Next I suspected the idle air control valve might be bad. I replaced it, but again no difference. I tested the TPS and that seems to be working properly. The throttle body appears to be clean. I'm just not sure what to do next...
I have not checked the MAF. I have a new one but I don't really want to replace it until after I replace the turbo, unless that could cause it to stall immediately? I am also going to remove the air filter and check the intake piping. Is there anything that I am missing as far as anyone can tell? Sorry for the long post, but I felt it was important to share all I've done up to this point.