Car Performs Better After 2-3 Min Idle Warmup

[stolen-gtr]

hi all

Ive just recently noticed that in the mornings if i let my car idle for 2-3 mins before i drive it, it performs as it should.

If i drive it straight away or within about 30 secs of starting it...it is quite sluggish...sounds more raspy and really have to plant it to get any sort of boost

I was wondering if maybe its not coming out of "cold start" or something to do with the thermostat but i have no idea hence the question

any help would be greatly appreciated as its driving me nuts haha

thanks

[Yts]

hi all

Ive just recently noticed that in the mornings if i let my car idle for 2-3 mins before i drive it, it performs as it should.

If i drive it straight away or within about 30 secs of starting it...it is quite sluggish...sounds more raspy and really have to plant it to get any sort of boost

I was wondering if maybe its not coming out of "cold start" or something to do with the thermostat but i have no idea hence the question

any help would be greatly appreciated as its driving me nuts haha

thanks

no offence here but why would you be wanting to drive your car hard right from turning the key without warming it up, next is depending on how much work you have done to the car with my experience stock cars generally dont have much of this happen but when you have bigger setups, ie upgraded turbos fuel lines clutches and what not they need to be warm to run smooth, just my two cents worth and prob has something to do with the colder weather coming in

[Keeper]

may be wrong here, but a good warmup allows the parts of the car to expand and all fit the running tollerances etc.

along with it allows the oil the get to the top of the engine and all the right places,

starting an engine and hoofing it straight away is just going to do damage to your engine

[stolen-gtr]

no offence here but why would you be wanting to drive your car hard right from turning the key without warming it up, next is depending on how much work you have done to the car with my experience stock cars generally dont have much of this happen but when you have bigger setups, ie upgraded turbos fuel lines clutches and what not they need to be warm to run smooth, just my two cents worth and prob has something to do with the colder weather coming in

hey Jeremy and Dave thanks for the reply

i understand about the warming up process, i like to let it idle for a minute or so but sometimes i cant due to time restrictions etc etc

i never boost let alone drive it hard until the oil has reached full operating temp, but even once it does why would the car not react the same depending on the initial idle time?

I wasnt under the impression that the car would react completely differently depending on how long it idles for.

also if this helps, it will only go back to "normal" after it has fully cooled down after sitting for a 4 or 5 hours

i appreciate the help though thanks

[Yts]

hey Jeremy and Dave thanks for the reply

i understand about the warming up process, i like to let it idle for a minute or so but sometimes i cant due to time restrictions etc etc

i never boost let alone drive it hard until the oil has reached full operating temp, but even once it does why would the car not react the same depending on the initial idle time?

I wasnt under the impression that the car would react completely differently depending on how long it idles for.

also if this helps, it will only go back to "normal" after it has fully cooled down after sitting for a 4 or 5 hours

i appreciate the help though thanks

as i said i didnt want to imply anything but the way you worded it sounded like that lol, i too have been in the same situation where u dont have time to letit warm up, and like you it does run a little slugish, although i have a 300kw setup and a built motor so like dave said the oil needs to be in all the right places for everything to work and when you have a torque turbo like my tdo6 there is very little turbo lag and it is almost like fuel cut and doesnt spool boost over 3000 rpms til warm, so i can sympathise with you and sometimes you think there is something wrong with the car, possible soloution could be to get an engine start remote so you can turn it on from your bed or something lol

[stolen-gtr]

as i said i didnt want to imply anything but the way you worded it sounded like that lol, i too have been in the same situation where u dont have time to letit warm up, and like you it does run a little slugish, although i have a 300kw setup and a built motor so like dave said the oil needs to be in all the right places for everything to work and when you have a torque turbo like my tdo6 there is very little turbo lag and it is almost like fuel cut and doesnt spool boost over 3000 rpms til warm, so i can sympathise with you and sometimes you think there is something wrong with the car, possible soloution could be to get an engine start remote so you can turn it on from your bed or something lol

fair enough i guess i will just let it sit for a few mins...

however after saying that, in a lot of the threads about "warming up" never seem to indicate any sort of performance difference after letting it idle for a few mins...(i could be wrong in assuming that)

[RBceffy25]

this is something i have always wonderd about. Every car i have ever owned has done this (Mazda 323, 626, Honda Accord, Mitsubishi Cordia, C32 Nissan Laurel) . However when I first buy a car I have noticed its not so bad if not at all. But I have always let my cars warm up from between 3-6 minutes or more depending on the time of year and its seems that the car/engine seems to get used to this condition and routine of warm up.

Can anyone else relate to this?

[skylinekid]

it can also come down to the tune. because of the cold start function with the coolant temp sensor the car is given more fuel when cold until it warms up basically a choke setup, then it is given the correct amount when warm. also with the idle air bypass valves they get dirty over time and dont idle at the correct speeds etc all just comes down to wear and tear. u dont drive ur car cold for very long neways so harden up wait till its hot and give it hell. my 2 cents

[stolen-gtr]

it can also come down to the tune. because of the cold start function with the coolant temp sensor the car is given more fuel when cold until it warms up basically a choke setup, then it is given the correct amount when warm. also with the idle air bypass valves they get dirty over time and dont idle at the correct speeds etc all just comes down to wear and tear. u dont drive ur car cold for very long neways so harden up wait till its hot and give it hell. my 2 cents

skylinekid you make a good point about the air bypass valve...which makes me wonder whether that might have something to do with it

the idle has been hunting a bit and generally idles smoother/correctly those times when its running "well"

i have a spare aac valve assembly i might swap it over and see if that makes any difference

thanks for the idea

[StealthX]

This condition is worse for MAP sensored cars. Not that that's much help for OP, but my set-up experiences exactly the same symptoms because its hard to get an accurate vacuum/boost/load signal when things are cold. Don't know why this is, but i imagine Air Flow Meter cars have a similar effect. The condition is definitely more pronounced with the more modifications the engine has i.e. aftermarket ECU, upgraded turbos, Intake manis, cams, injectors etc...

I reckon its a combination of a couple of things:

-Oil is cold and more viscus, thus has more resistance on rotating parts (crank, rods, cams, oil pump etc...)

-Engine is cold and rotating parts are that little bit smaller due to thermal expansion, therefore piston-cylinder wall clearances and thus compression isn't the same. This is even more pronounced for cars with forged pistons or aluminum blocks (ally vs steel pistons, different metals expand at different rates).

-The ECU injects different amounts of fuel on cold start-up, and the AF ratio vs ignition timing (when cold) won't bring about the best, most responsive 'feel'. Also the stock ECU has the perfect tune for cold start-up, to compensate for the above factors, as soon as you start to change things, (as Yts said) this throws that factory tune out a little.

-Extra loads put on the engine (electrical loads (alternator), high steering angles (power steering), air con (A/C compressor).

-Lower intake temps because the intake manifold and head are cold.

In short, it's always good to let your engine warm up to operating temp. before giving it a sting, everyone knows this...

[TiTAN]

my car has a rebuilt engine, larger turbo, injectors, map based ecu etc. it gets about 15-20 seconds for the oil pressure to come up and then i am off (obviously not thrashing it) and this has only happen when there was a couple of cells out of whack in the tune that meant it ran super lean and lost almost all power as there was next to no fuel going in.

[TiTAN]

it can also come down to the tune. because of the cold start function with the coolant temp sensor the car is given more fuel when cold until it warms up basically a choke setup, then it is given the correct amount when warm.

you would be surprised how little time the stock ECUs give the engine before reverting to closed loop cruise and pulling it back to 14.7:1 they cant run it rich for long as it hurts the emissions tests they have to pass and destroys the cat.

[The Mafia]

rofl at this thread.

Planting it to get boost while its cold?

Good luck with the engine rebuild.

[rob82]

hi all

Ive just recently noticed that in the mornings if i let my car idle for 2-3 mins before i drive it, it performs as it should.

If i drive it straight away or within about 30 secs of starting it...it is quite sluggish...sounds more raspy and really have to plant it to get any sort of boost

I was wondering if maybe its not coming out of "cold start" or something to do with the thermostat but i have no idea hence the question

any help would be greatly appreciated as its driving me nuts haha

thanks

What model and what mods? Does your O2 sensor work?

Edited May 13, 2010 by rob82

[discopotato03]

For my 2c engines can feel sluggish when stone cold for three reasons .

Firstly the cold gun effect where you're losing a significant amount of combustion heat into cold piston crowns/valves/chambers so less heat to develop cylinder pressure .

Secondly oil shear drag from cold oils esp mineral ones .

Thirdly warm up mapping is different to get heat into the thing quickly because often this is the dirty time for most engines emissions wise . The cat has to be brought up to temp as quickly as possible to be able to work as intended .

I like to give my engines a short idle period to get the fluids circulating internally . One thing you will notice is that a good synthetic oil doesn't have as much drag as mineral ones tend to when cold .

I think what you are feeling is computer mapping that has greater emphasis on warming the engine up rather than giving best performance .

As people have hinted having some mechanical sympathy goes a long way with cold engines , also don't forget the gearbox and diff oils work better with some heat in them and you only get that after driving for a while .

2c spent , A .

[GTScotT]

he did state hes not planting it, just notices it goes better if he warms it up idling rather than driving easy.

I think this is a common thing, ive experienced it on most all cars ive driven. One of my cars felt lazy if i did the opposite lol, it prefered to be driven within 30 seconds of starting and warmed up with easy driving, then it was alive.

I have a feeling that this is oil related, if ur due for a service soon try run something of higher grade. The best oil I know of is neo gold and you can get it from gccorp.com.au delivered to your door for about $70 for 5L. My motors always ran tops on that stuff, it turned my sludge filled SR to a new looking motor within 1 service (talking about under the rocker). Its also an extended interval oil, i usually keep it in for about 8000.

GL

[Rock&Roll]

My whole car feels like I do when i first get up in the morning.

sluggish, wastegate flutter....

They say dogs look like their owneds....

[The Mafia]

hi all

Ive just recently noticed that in the mornings if i let my car idle for 2-3 mins before i drive it, it performs as it should.

If i drive it straight away or within about 30 secs of starting it...it is quite sluggish...sounds more raspy and really have to plant it to get any sort of boost I was wondering if maybe its not coming out of "cold start" or something to do with the thermostat but i have no idea hence the question

any help would be greatly appreciated as its driving me nuts haha

thanks

he did state hes not planting it, just notices it goes better if he warms it up idling rather than driving easy.

Its common knowledge to let any engine get to normal operating temperature before putting any load on it.

Reasons:

- Oil is as thick as honey and can't be pumped or splashed around as easily

- Metal expands and contracts with heat.

- Pistons are smaller so they expand in the block faster in the block making them slightly tighter until warm

- Thick oil pushes out seals

- Engine failure

This should be taught at school. I can't believe some people don't know how obvious this is?

Edited May 14, 2010 by The Mafia

[paulr33]

as the others have said, just drive it normally (dont load it up, dont bring it on boost) until the engine is warm

wamr is considered around 50deg water temp - or when the water temp guage on the dash starts to move

[GTScotT]

i never boost let alone drive it hard until the oil has reached full operating temp, but even once it does why would the car not react the same depending on the initial idle time?

Dont get your nickers in a twist mafia, he did correct himself