the colder it is the harder it is to start

[killablue240]

my s13 sr is hard to start when it is cold outside. i have to crank it and keep pumping the gas for it to start. if it is really cold it can take up to 3 minutes to start. once the engine is warm it will start right up. any ideas?

[cheapscheisst]

the colder it is the harder it is to start

tell me about it

[killablue240]

huh... from what i hear its a common problem usually the iacv but i was just wondering if anyone out there has actually fixed theirs.

[redtop91]

Mine is harder to start in the cold but it cranks and wants to die for about 5 seconds then it jumps to 1.5k and then back to 1. IACV

[brandonlgilbert]

Dude I have the same problem. It jumps to 2k when it first fires up then drops and starts to stumble at around 800 until I blip the throttle (sometimes have to go through this twice) then it settles down to 1500 and then when it warms up it settles around 1000.

[S13FASTBACKSR]

when the engine is cold there is nothing wrong with it jumping up to about 2k or so and then drop down..thats just what they do a lot of the time when they are that cold..this guy doesnt have that problem though..he cant get it to start when its cold at all...what oil weight are you running my friend? possibly its too thick and you have to go down a weight or two

[killablue240]

im running the thickest mobil 1 synthetic extended performance, i know its not the specified oil but im trying to protect it since i race it. the plastic screw on my iacv is seized so i cant even try to adjust it.

[S13FASTBACKSR]

if your car idles fine when its warm then im sure that the problem has nothing to do with the iacv..it sounds like your oil is too thick for a cold start..exactly what weight is it?

[killablue240]

15w50 i shouldnt use it so thick for the winter but i havent put enough miles on it to change it yet. what do you think is a good weight to put in it?

[S13FASTBACKSR]

i am unsure of NM weather but if it gets really cold there..(not gonna be temperature specific) i would go with 10w30..if it gets really really cold possibly 5w-30..when it warms up I would use 10w-40..thats what i use in south florida atleast and i think summer temps here are same as yours? but ya bro...15w-50 is definately waaaaaaaaay too thick for the winter..thats your problem i would put my money on that for sure

[killablue240]

im getting close to an oil change and im gonna try some 10w 40. the winter is mild here, the summer is hell then again its a desert lol. we'll see what happens

[kamikazestorm420]

maf, cts, or iacv.

had the same problem.

[S13FASTBACKSR]

kamikaze did you have any other symptoms besides just not starting when cold? i highly doubt that the maf, cts and iacv would cause ONLY a cold start and absolutely nothing else..its obvious his oil is waaaaaay to thick for the winter

[kamikazestorm420]

kamikaze did you have any other symptoms besides just not starting when cold? i highly doubt that the maf, cts and iacv would cause ONLY a cold start and absolutely nothing else..its obvious his oil is waaaaaay to thick for the winter

mine would take FOREVER to crank up and start when its cold (i run 15w-50, changed thickness didnt change a thing). checked everything and cleaned everything but the maf, still the same thing. went and took out the maf, cleaned the sensor, unscrew the top section and there was a lot of rustish (don know if thats word) stuff on there. cleaned it up, BAM, cold idle, starts right up. when it was warm it would start right away, no loss in power, holds boost (7psi) and accerelate(sp) like a champ. problem only occured during cold starts.

[killablue240]

interesting... but i took an ohm meter to the cts and tried three different mafs, and all the same results.compression is good, i checked all wiring and it looks good, only other things to mention are that when coming to a stop in neutral the rpms dip to like 400 then go back up to about 800, and codes for CAS and knock sensor.

[S13FASTBACKSR]

the idle dropping to low after putting the car in neutral is more than likely either your bov spring not being tight enough or the bov needing to be recirculated..thats cool how the maf was the problem for cold starts ive never heard of that before very interesting..and your getting codes for your cas and knock sensor? do you hear any knock? i would pull the knock sensor and see if it looks corroded and pull the cas and see if its burnt out or anything if you see anything suspicous at all

[kamikazestorm420]

interesting... but i took an ohm meter to the cts and tried three different mafs, and all the same results.compression is good, i checked all wiring and it looks good, only other things to mention are that when coming to a stop in neutral the rpms dip to like 400 then go back up to about 800, and codes for CAS and knock sensor.

have you checked the cts when its cold AND hot? both of them have to be ok. the rpm dip can be your bov but can also be the tps. when you rev, the rpm will go up, and come back down fast until around 1500rpm where itll slowly go down to neutral. that is your tps working. so the rpm dip MIGHT be your tps. check the voltage on that.are you sure those mafs that you used was in good condition? if you have a check engine light, then you should check those first before doing anything

the idle dropping to low after putting the car in neutral is more than likely either your bov spring not being tight enough or the bov needing to be recirculated..thats cool how the maf was the problem for cold starts ive never heard of that before very interesting..and your getting codes for your cas and knock sensor? do you hear any knock? i would pull the knock sensor and see if it looks corroded and pull the cas and see if its burnt out or anything if you see anything suspicous at all

honestly, i didnt know that maf effects cold starts either. thats why i checked the maf last lol. my maf was fine in the voltage but when i checked resistance it was a little off. you have to check both resistance and voltage, and see if both of them are in range.

[S13FASTBACKSR]

honestly, i didnt know that maf effects cold starts either. thats why i checked the maf last lol. my maf was fine in the voltage but when i checked resistance it was a little off. you have to check both resistance and voltage, and see if both of them are in range.

thats cool man, you learn somethin new everyday..just like the tps causing the idle to drop..to me it would be if the tps was the problem it would cause misfiring or richness or leanness too..but you never know..how he describes the idle dropping is it dropping fast to 400rpm..thats why i think its the bov spring not being tight enough or it needs to be recirculated because the maf reads that air and then tells the ecu to tell the injectors to put more fuel in but once the air is let out by the bov the a/f ratio is wrong and the idle drops because too much fuel is put in

[kamikazestorm420]

thats cool man, you learn somethin new everyday..just like the tps causing the idle to drop..to me it would be if the tps was the problem it would cause misfiring or richness or leanness too..but you never know..how he describes the idle dropping is it dropping fast to 400rpm..thats why i think its the bov spring not being tight enough or it needs to be recirculated because the maf reads that air and then tells the ecu to tell the injectors to put more fuel in but once the air is let out by the bov the a/f ratio is wrong and the idle drops because too much fuel is put in

if he is venting his bov to the atmosphere then he should fix that first and then check the tps. because like you said, venting the bov is known to do that

[S13FASTBACKSR]

ya killablue step 1 tighten bov if that doesnt work then step 2 check tps voltage and continuity..voltage should be .45v-.55v at idle and 4.5v at w.o.t. if that stuff checks out (dont forget continuity) then recirculate your bov. also as far as the starting problem goes do what kamikaze said about cleaning your maf but since you tried 3 im sure not all are bad then i would change the oil

[killablue240]

im going to check the tps values, the bov is atmospheric and the spring is tightened i was thinking that maybe the bov seals were leaking and pulling in unmetered air but i sealed the whole thing off and no change, the cts is within specs cold and hot. somehow im leaning towards the tps but we will see.

[nuts510]

a common problem I've ran into with poor starting when the car is cold is the head Sender on the thermostat housing has got a corroded connection or gone bad itself there is another plugged it is easier to get too that has three wires going to it the third is for the temp gauge but if you unplug it at this point and check it for continuity with a meter if you don't get any reading you deftly got a problem of resistance is high your get a high reading

[Mistaken]

Im having the same problem as the original poster, Im in chicago and the weather has been pretty cold. I am currently running 10W-30 mobil 1 full synthetic in my SR. I have to hold my foot to the floor while cranking on a cold start. Once it fires it idles great, and it starts up fantastic when warm. Any ideas? Ive been doing a lot of searching and a lot of research and i still cant figure it out.

[killablue240]

hey mistaken, do you have a front mount intercooler? just asking because i have a theory but i still havent been able to fix this problem and know a few other guys with the same problem

[Mistaken]

Still running the factory side mount until i figure out the cold start problems.

[killablue240]

when your car finally starts does it smell like gas?

[kamikazestorm420]

did you try those couple things i recommended the OP to check?

[Mistaken]

No smell of gas and i havent checked those problems yet. I cleaned out the IACV but now i have it out since the motor is coming out for a new head gasket, hoses, and im going to paint the engine bay.

[Mistaken]

The maf will be the first thing i check once it goes back in next week.

[Shahsoon]

change the fuel pump! i had it before and when i changed it it worked from the first time.You can try this by putting a few spoon fulls of petrol in the injectors from thhe outside when the car is cold and it will start from the first time.You can get to that pipe from the one that leaves the intercooler to the injectors.