I really hope someone has an answer to this one.

When the outside temp falls below approx 40 degrees Farenheit, my car refuses to start on the 1st attempt. The engine turns, it starts, but then it stalls and I have to start the car again. This winter, we have been having some unusually cold temps (for those of you in Canada--DON'T LAUGH :wink2: and the temp has dropped to almost zero. On those mornings, I have to make a 3rd attempt to start the car.

Keep in mind, I try to let the car run on its own, hoping it will fast idle, but at best, the car will just idle slightly above normal idle speed until it is warmed up and I'm assuming is no longer operating in a closed-loop system.

The dealership insists on me leaving the car with them overnight. They claim they will connect to the computer and the car could tell them what's going on during this very brief cold start up. I don't believe them, because I thought the closed loop start up doesn't involve the computer's adjustment of fuel mix, timing, etc.?

Does anyone else have this problem and, if so, did you get it fixed? What was the problem? I wish the dealership would just go ahead and change a sensor like a cold start up valve or something, instead of insisting that they don't have a clue what it could be. The first time I took it in with the complaint, the guy testing the Throttle position switch and said it was bad, replaced it but it never solved the problem.

Your dealer is correct; he can interface with the "HISCAN" and can do a "FLIGHT RECORDING" of various sensors and ECM output signals. If the problem occurs only when cold, then he has to test the system under these conditions.

>>I don't believe them, because I thought the closed loop start up doesn't involve the computer's adjustment of fuel mix, timing, etc.?
<<

Startup is a open-loop operation, even if the engine is warm. As from 50°C, the ECM is starting to go more & more into "closed loop" operation, and continuous adjusting mixture an ignition time, as conditions demand it.


This post has been edited by duke: Feb 6 2005, 04:22 PM

GTV6?
alfa? kewl! :D

Got some really simple advice on this one and I will definitely try it as soon as my tank is in need of filling up.

I ALWAYS run 92/93 Octane gas, because the owner's manual states a minimum of 87 octane, but it doesn't state that it is recommended. I figured my Tib would run better using the highest octane available.

Well, other Tiburon owners stated that if they use 89 or 87 octane, they experience no problem with cold start up. However, using the higher octane, below 40 degrees it will stall when trying to start (exact same problem I describe mine as having). Considering I have no mods to the air intake (such as CAI) then this car definitely should not be hesitating/stalling.

Your car has a 10:1 compression ratio, and is best to run on 92 octane. This should not cause a stalling problem. However, you now can use lower octane since the season is colder, the colder air will lower the detonation point (engine knock, which you willnever hear because of the knock sensor). The USA is using a lot of methanol mix fuels, which we here in Canada have some performance problems. Wen I drive into the STATES with my 2000 Sonata 2.5 V6, I use EXON fuel and found it to be the better performer.

I'm almost positive this Tib has a higher compression ratio than did my old car a 1988 Nissan 300ZX, and it always ran poorly if I didn't use the highest grade.

Even if using 89 or possibly 87 octane will cure my cold start problems, I will definitely switch back to the highest octane when the season changes and temps go back up.

on my last trip to Florida in january, on the way back to Canada on the H-way, I ran low on gas (low fuel light on) and filled with other than EXON. I can't remember the brand, but the engine stalled several times at stops, till I got back on the H-way. You may wan't to change the fuel brand, and see the result ?????

I have the 03' tibby gt also and i live in South Fl and even when it gets cold down here my tibby stalls also..... I also have a cold air intake so i guess its just doing its job and making the air even colder than the temperature outside!!! But im not stressed over it...anyways goodluck if you find something out!!---- sarah

i'm not disagreeing with with the above replies , however i have used 87 octane gas in both my tibs , adding injector cleaner at every oil change . (10.5 & 10.0 cr) . Both engines idle smooth and run to red line effortlessly . I would have a dealer check for fault codes etc., something is wrong obviously .

I live in a border city and use U.S. gas in my tib and my wifes' windstar exclusively .

This post has been edited by mfp: Apr 22 2005, 07:10 PM

I live in Germany and have never had a problem starting my Tib.

I dunno what the deal is I run 93 octane and never go anywhere besides mobil or chevron any other place isnt good enough for me! LOL But i dunno i think we should get to the dealer but hey black16 good luck hope you get it fixed!!

~~~ Sarah

putting anything over 87 ctane is pointless for the car..the ECU is tuned for 87 and thats the maps it uses....anything above doesnt help you, it is just more money out of your pocket...for cold starts i recommend turning the key to the on position for a vfew seconds (to allow the fuel pump to pump fuel to the engine) ... then try to start it...on start up, if you have to, rev it a little bit (not over 3k) and then it should be fine

OK thanks Malik I didnt know that about the whole octane deal!! Your a lot of help and yeah man that gas is crazy$$$$$ ~~ Thanks

It says: MINIMUM 87 OR HIGHER is recommended.

As per the engineers at HD-Ulsan, the HP value is established with 92 octanes AKI (+-98 RON). Yes, the ECM can adapt to 87, due to the fact that the knock sensor will indicate when there is a “self ignition” (detonation/knock). When this happen, the ECM will retard the ignition time to prevent further detonations. We all know what happen to the engine power, when the ignition is retarded.
However, it is advantages to use 87 in the cold winter time, it makes the mixture more ignition friendly, and the cooold intake air will lower the detonation temperature threshold.

so the 93 octane is ok though right??? I mean its got to be some sort of improvemnt than lower octanes?? Right?? Fill me in....

~~~ Sarah

93 is perfect.

you will notice no difference if you run 93