joeyjr25

So I've been having the same running issue till the car starts warming up as a lot of other people. I had replaced the chts and tested the sub harness in the past with no change. I recently rebuilt the top of the motor since I had to pull a head off anyway to fix a snapped spark plug. In the process I deleted the idle controls and cold start valve after reading most people do it with no negative consequences except needing to hold their foot on the gas a minute or so while it warms up. Well now on the first cold start after the car cools off not only is the original issue there but I have a real hard time getting it started. It'll crank, backfire and stumble a few times then stall. Start stumble and backfire and miss a few times then will run like it used to till it starts warming up (with my foot on the gas to simulate the cold start valve of course) then once warm it runs the best it has since Ive owned it.

So I guess my question is can deleting the cold start valve make it that much harder to start or am I having another issue and where do you guys think I should be looking for it

Stock Ecu

joeyjr25

a video of me trying to start it tonight after work

rogerz

Sure you don't have an s130 because the z31 never had a cold start valve or you just randomly took something off of which you have no clue what it was.

joeyjr25

Yeah it does. It's called air regulator though. On the passenger side of the plenum. S130 has a cold start injector I thought

joeyjr25

I can't believe out of 130 views no one head any useful advice for me. For the record incase anyone else comes across the same issue, when I set the idle on the throttle body I forgot to adjust the tps (it was getting late and I ran out of energy and was too excited to see my car running again after 2 months). Now it starts up just fine.