ok i searched but there is not specifics i found, i am a retard however so, maybe i didn't search for the right thing..

anyway, why is it, my car will not idle it just dies, until its warm, usually until the EGT reaches 800-900 Deg. F. once its warmed, its fine... but until then... i have to hold the gas pedal down to keep it at like 3000 rpms, and even then it some times starts to stall..

Any clues? and yes, i checked the plugs i even put in new ones.

 

What mods do you have? Have you checked for any vacuum leaks? Also, do you have a SAFC? If so I would check the settings there too. Maybe try adjusting the idle screw on the throttle body and see what that does.

 

rable rable rable. that's a good one?

 

that wouldn't have any thing to do with it. If it was the idle screw the car wouldn't stay running at all, not even when warm.

 

Yep.. the idle stop will mean the car wouldn't idle well regardless.. HOWEVER there is an idle air bypass control solenoid that may be disconnected on the throttlebody, so check that.. Also, when the car is cold it runs in open loop mode, so your issue is with open loop idle, or a timed vacuum source that is leaking.

Before I can suggest anything, I need to know exactly what you have on the car since I can name 30 or so possible reasons for this depending on what you have or don't have.

 

oh man,

272's, HKS RS kit, 3" tb those are the basics right i know its an issue with open loop because after about 2 minutes of keeping it running, its fine

 

here's a better detail

http://forums.dcevoclub.com/vbgarage.php?do=view&id=1

 

I would look at and make sure the cold idle pin on the ecu is not loose, that is what was wrong with my evo. It would not idle but if you kept the car revved up after a min or 2 it would be fine.

 

On my 98 eclipse GST I had a similiar problem. It was the ISC, idle speed controller on the TB. Just out of curiosity, did you reconnect the coolants lines on that 3" TB?

 

I think he means 3" turbo-back exhaust.

 

Whoops, my mistake. Disregrad what I said earlier.

 

Ok.. if its the HKS Intake kit, it uses a hard MAF pipe, it drops the MAF frequency due to its lower restriction so the airflow through it is a little slower.. But normally that wouldn't effect things.. But your running HKS cams, You can reduce the cam overlap with timing gears so you boost your idle vacuum while in open loop, or if you have an S-AFC or any piggyback setup, you'll need to add about 2-3% fuel.. the open loop idle is probably real lean at the moment, when the car is cold, it should be pretty rich..

I'm assuming you don't have an upgraded pump or injectors since you don't mention it..

However there may be an easy fix and that is to add an upgraded fuel pump (Walbro 255), the better pump should cause the open loop fuel maps to go about 2-3% richer which should help your idle. Keep in mind that you'll be richer throught your entire open loop maps.

I'm assuming you do have a way to tune for this, if your using a flash, you can add am S-AFC piggyback, or have it reflashed to do the same thing.

The easiest explanation is that closed loop long term and short term trims adjust to changes made in airflow and mixture, and will always try to maintain 14.7:1 air fuel mixture.. The giveaway is idle mixture runs pretty lean in open loop till the car warms up (as lean as 16.5:1) If you recall the older carburators, there's something called a choke, basically it would choke the air allowing more fuel to enter the engine.

 

I think he does have some fuel work done.... he has 660's and a 255lps fuel pump..... sounds like something is ****ed up aaron.... gimme a call and i'll come over and help ya out...

taylor

 

The point of a choke was to make the car run richer, not leaner though. It would be very odd for Mitsu to set our cars up to run leaner than usual from the factory at startup. I just tested my car with my portable wideband for the first time yesterday. It has an SAFC (tuned by Buschur's shop), 660s and a 255 lph pump. With a cold start, idle AFR went right to 14.7:1 immediately. I do have some minor stalling issues, but they aren't too bad (only when I jump off the throttle and push in the clutch after abruptly moving the car forward). I did notice that when coming to a stop after sustained mid-RPM operation, when I sometimes get some idle stumbling, that the idle AFRs are lean at around the high 15s or low 16s. As the car sits in place at a stop light the idle AFRs return to about 14.7 and the idle smooths out, which I assume is the short term correction factors adjusting (need to verify that with a scan tool), so I must have the SAFC tuned too rich for cruising (where presumably the correction factors are pulling fuel to correct and causing the idle problem when I stop). I'm suprised that the factory computer has cruise RPMs and idle RPMs mapped into the same fuel trim cell though.

Have you verfied this with a wideband? I can't see how the bigger pump would affect fueling in offboost conditions. If it does then the fuel pressure regulator isn't doing its job.

Nastea, did your car just start doing this all of the sudden, or did you just add a mod? Does everything sound okay in the motor mechanically? One Evo friend of mine just had a lobe go bad on an HKS cam, so you can't completely rule out mechanical failure. The Walbro pumps also have been known to fail. Certainly what you are talking about could happen with a faltering fuel pump. The best way to track this down would probably be to start with an OBD II scan tool and see what's going on. I'd drive it easy until this is sorted out since a fueling issue could cause detonation in normal driving. Good luck.

 

I have 660 cc injectors and a 255 lph walbro and i have a SAFR, but i just need to program it... i'll work on that today and let you know thanks jack