im having hard time starting up the car(engine cold; not warmed up), and whenever i come to stop rpm drops too low (around 500).

when i start the car(engine not warmed up), i have to slightly step on the throttle to start it up and hold on to it till rpm stays still.
if i dont step on the throttle, engine wont pick up its regular idle rpm and just die.

even if im driving (engine is warmed up) and come to a stop
rpm drops to 400~500 and comes back up to 1000.

im guessing its vacuum problem somehow. however, i have boost gauge
and i dont see vacuum gauge go down when im stepping on the throttle.

if anyone have an idea please let me know.

 

I've had the same Issue on cold starts...never found the problem so I just kept giving it slight throttle and it's been fine. Looking forward to what others have to say though

 

I am having a similar problem also.

Sometimes when I start my evo (could be cold or warm) it starts idling low around 500 for a couple of seconds and then picks up to 1000 (I dont touch the accelerator during this time) but then its fine, its strange

Im also having a similar problem like you have when you come to a stop but for me its when say im turning the car in a small area when I have to go back and forth a couple of times the cars RPM's drop again to about 500 and nearly cuts off just when I let off the accelerator and press the brake and clutch down Its pretty annoying, but if I give it pleanty of revs going back and forth its fine but then theres consequences to that

If anyone has ideas please tell me

 

Just thought maybe it could be the IAC Valve? Is it possible?

 

Have you reset ecu by just disconnect battery? Most idle issue that ive been heard/had was related to air flow. Also its good to try clean IAC valve too. Good luck

 

yes i have cleaned out iac, also cleaned out tps. and yes i did reset battery.

anyways, here is another story.

i always go Sunoco / shell for gas. 93. I go to sunoco because its a lot closer to my house.
i had a feeling that it could be the bad gas station, so i went to the shell and put 93.
after about half tank of gas, it got better. And the car starts up well.

however, now im getting high rpm idle (around 1200~1500). what now?

 

Does it only go up to them revs when you start it cold first or all the time?

 

For some reason my phone won't let me copy the link but there's a thread on resealing the throttle body and putting a film on the plate.
My car does the same thing, idle drops when I press in the clutch and if im driving moving to a stop it will die. Put in new iac didn't fix the problem so I'm doing the above noted procedure when the spray comes in. Letcha know if it works hopefully it does

Just a thought for you tho

 

Guess I need to clean that....same problem.

 

clean the MAF

 

could be an IC motor or a temp sensor telling the car to add to much fuel

 

My evo sometimes would be hard starting and idled ****ty when it did that. So I cleaned out the EGR valve which was full of dirt and dust and it seems to be better starting and stuff since. No harm in cleaning it out anyway.