Car works, but starts weird

[604_R32]

I've noticed a recent problem with my rb20.

Whenever the car sits for lets say around more than 9 hours, and you go to start it, it starts fine, but then the revs go down and stalls, unless you give it a little push on the gas pedal, as soon as you do that, the car goes to its normal idle completely fine and the car runs perfect.

If the car has been run earlier in the day, it starts fine, but when it sits overnight, or for as said before, longer than about 8-9 hours, it does this.

What do you guys think? Clogged injectors? Fuel Pump?

[amnash]

nah
could be as simple as your battery is starting to die off
whens the last time you gave it a good once over?
clean maf, check for vacume leaks, clean/test coilpacks, test alternator with multi meter(get car started and read voltage from battery terminals, should read 13-14v), change fuel filter etc...

check easy stuff first then move on to stuff like the pump and injectors becasue once you take out the injectors youll never get them to seal again...lol

[604_R32]

Well I got the car about a week ago haha

[mfroese]

Mine has done that since I bought it 3 years ago. Nothing to worry about. Only takes a slight throttle on start to keep it idling. If warm it starts right away without throttle.

[Nismo_line]

same thing. when i start my car and its cold its kinda a ruff start but little tap on the gas and shes good to go. warm start theres no problem what so ever

[Phillyb]

Exact same thing with mine haha I thought I was the only one

[Skym]

That's the first time and after start tables, etc.

First time is when turning key and is not too rich and then let go of key and it hits the rich after start table which makes the revs drop and engine could stall. You need to retune ECU to suit mods. I noticed it started to happen after fitting exhaust. Colder the coolant is, the richer it gets and is even harder to start.

Key I found to starting is keep cranking engine for 5-10sec or so (to get pistons pumping, sucking more air into cylinders to combat the rich start) and then let go of key.

Pressing throttle just opens the throttlebody more and does the same thing as cranking engine longer. Also using wrong oil (too thick) adds to the starting problem.

Gets worse if engine has intake airleaks. Check intake hose clamps 1x a week as they undo themselves due to engine vibration, especially when not tightened enough.

[amnash]

Well I got the car about a week ago haha

if you just bought it then its an even better idea to give it a once over. it doesnt cost much, mostly just inspections

[604_R32]

Yeah I'll be doing that this week for sure

[nelsonmxmarc]

TPS positioning it seems.
Check the voltage at the TPS and see what it reads, i can almost guarantee it's rated too low. Generally if you need to manipulate the throttle on startup, the TPS voltage and warm up maps do not correspond the setting it's at on the TB. Reset (zero off) to .48 volts, it should clear up your issue. Otherwise, it could be your IAC, which is your intake air control which opens on start up. Generally they fail, as they're a swing gate assembly and tend to deteriorate in time. This however, is not necessarily an issue. I run my car without one, and simply rely on the TPS for air control on start / driving conditions. So check the TPS voltage then work from there!