Cold Reving

Xantia2.0 · Unread post by **Xantia2.0** » 12 Sep 2010, 15:55

I was just wondering, I know most car's engines need to be warm before you can rev past 3,000RPM, but there are some engines that can cope just fine reving high when cold. I always find myself speeding up to about 30MPH before even leaving 1st gear when I leave for work in the morning, it's not deliberate, my mind is just on other things.

The reason I'm asking is recently the car has started "ticking" when it's cold, at idle. It ticks about 2-3 times a second.

Is that because of my bad driving habit of cold reving the motor ?

I always change the oil every 5-7K miles and make sure it is above the MIN mark (I check all the fluids every week) and add an oil additive when changing the oil to help it lubricate better.

So, question is - Can the 2.0 16V I4 cope with cold reving or is it damaging my engine ?

I know this might seem pointless but I just want to know if that tick is just the engine getting old or if it is because of me!

spider · Unread post by **spider** » 12 Sep 2010, 18:34

A post went awol

, I see what the staff did there

Back on topic:

I would not really advise going above 3k with a cold (petrol) engine really.

Most wear happens when they are cold anyway, so its best to keep rpm down a bit if possible.

Its only recently they started to protect cold engines with such things.

MikeT · Unread post by **MikeT** » 12 Sep 2010, 19:38

Thank you whoever the moderator/admin was.

OP, neither labour nor thrash a cold engine. Revs make oil pressure and you need as much oil pressure as possible as it doesn't flow so well cold. I can only guess the ticking is valvetrain wear as the top of the engine is one of last in line for oil after startup.

Unread post by **Dommo** » 12 Sep 2010, 20:48

A serious reply coming up.

Firstly - Assuming your gearbox has the same ratios as the CT engine (a couple of 0-60 runs on youtube seem to suggest they are very similar), 30mph in 1st gear is near enough the rev limiter at around 6000 rpm. And doing that with cold oil is not a good idea - as I'm sure you are aware, cold oil does not lubricate anywhere near as well as warm oil (so don't do it

).

Secondly:
"I always find myself speeding up to about 30MPH before even leaving 1st gear when I leave for work in the morning, it's not deliberate, my mind is just on other things."

Should you really be driving a car in that state if you don't realise you're forgetting to change gear? What else are you not noticing?

Unread post by **myglaren** » 12 Sep 2010, 20:54

I think most people would be changing up at about 1200 revs completely subconsciously, it is practically an automatic response and doesn't require much in the way of thought.

Xantia2.0 · Unread post by **Xantia2.0** » 13 Sep 2010, 09:57

First off - What about admins sorting something out ?

And second - It's not like I'm completely in a mind of my own. I'm just thinking what I've got to do for the day, but does make me forget to change hear earlier! Also, because I drive an automatic quite a lot these days when I do drive a manual I'm looking at the tach thinking - WHY WON'T YOU CHANGE GEAR!?!??

Then of course I see the Citroen logo on the steering wheel and realise why it won't change gear!!

XantiaMan · Unread post by **XantiaMan** » 13 Sep 2010, 09:59

Xantia2.0 wrote:First off - What about admins sorting something out ?

And second - It's not like I'm completely in a mind of my own. I'm just thinking what I've got to do for the day, but does make me forget to change hear earlier! Also, because I drive an automatic quite a lot these days when I do drive a manual I'm looking at the tach thinking - WHY WON'T YOU CHANGE GEAR!?!??

Then of course I see the Citroën logo on the steering wheel and realise why it won't change gear!!

Get off the road.

rmunns · Unread post by **rmunns** » 13 Sep 2010, 11:43

Never 'rev' any engine whilst cold. Also, it's recommended that you let a turbocharged engine idle for 1 or 2 minutes after a run, especially if the turbo had recently been working hard, before turning the engine off. For example, motorway service areas, top of hills etc. This is to help prevent carbonisation of the oil remaining in the hot areas and subsequent risk of damage to seals.

Sid_the_Squid · Unread post by **Sid_the_Squid** » 13 Sep 2010, 14:23

It could be the carbon canister valve ticking, does the frequency or the tick rise & fall with the engine rpm?

Also yes cold revving bad, even with mad expensive oil.

Unread post by **CitroJim** » 13 Sep 2010, 16:24

Xantia2.0 wrote:Also, because I drive an automatic quite a lot these days when I do drive a manual I'm looking at the tach thinking - WHY WON'T YOU CHANGE GEAR!?!??

No. That should not happen. I, in common with may others on here, drive an automatic and also drive a manual regularly.

When I get into whatever car, a mental switch is flicked to indicate auto or manual. It never fails. It's so ingrained that I automatically (no pun) rattle the gearstick on a manual car to check it is in neutral but never do that when I get in an automatic.

It's one of those "autopilot" things you do. Like I always automatically depress the clutch on a manual before starting. I never even try to do that on an automatic.

On the revving subject, you must never rev a cold engine even though you can. Modern engine management systems are so good nowadays that the engine is smooth from word go. That does not mean to say you should. As said, most wear takes place when cold.

It is often said that engines last well in hydraulic Citroens due to the enforced period of idling after a cold start as you await the establishment of hydraulic pressure. I'm a believer that there is something in that...

Xaccers · Unread post by **Xaccers** » 13 Sep 2010, 17:01

30mph in first also doesn't sound right, 1st gear is so low in Xantias, as has been mentioned before you'd be screaming the nuts off the engine.
To do so without realising whilst knowing you're pulling away (so not having mis-selected a gear) is implausable.

One of your first threads you claimed it was a fact that colder engines last longer and cited that you tuned your cars to run at around 40C, yet you've posted about steam from the exhaust and now you're asking if running an engine when cold damages engines.

Xantia2.0 · Unread post by **Xantia2.0** » 17 Sep 2010, 15:20

CitroJim wrote:
Xantia2.0 wrote:Also, because I drive an automatic quite a lot these days when I do drive a manual I'm looking at the tach thinking - WHY WON'T YOU CHANGE GEAR!?!??
No. That should not happen. I, in common with may others on here, drive an automatic and also drive a manual regularly.

When I get into whatever car, a mental switch is flicked to indicate auto or manual. It never fails. It's so ingrained that I automatically (no pun) rattle the gearstick on a manual car to check it is in neutral but never do that when I get in an automatic.

It's one of those "autopilot" things you do. Like I always automatically depress the clutch on a manual before starting. I never even try to do that on an automatic.

On the revving subject, you must never rev a cold engine even though you can. Modern engine management systems are so good nowadays that the engine is smooth from word go. That does not mean to say you should. As said, most wear takes place when cold.

It is often said that engines last well in hydraulic Citroëns due to the enforced period of idling after a cold start as you await the establishment of hydraulic pressure. I'm a believer that there is something in that...

Eh ? If a car is in neutral no clutch depression is needed. It's only American cars that have clutch "safety" switches causing you to have to depress the pedal before starting!

Xantia2.0 · Unread post by **Xantia2.0** » 17 Sep 2010, 15:22

Xac wrote:One of your first threads you claimed it was a fact that colder engines last longer and cited that you tuned your cars to run at around 40C, yet you've posted about steam from the exhaust and now you're asking if running an engine when cold damages engines.

No, after an engine has been running for a while (no matter how cold the engine runs) the oil heats up and the gloopy texture goes away = lubricates better.

Xaccers · Unread post by **Xaccers** » 17 Sep 2010, 15:40

It is good driving practice to start cars with the clutch pedel depressed.
My Megane (that would be a non-American car) would only allow starting if the clutch was depressed.

As for your oil comment, if your engine is running at 40C then no matter how long you run the engine at 40C for the oil will not reach the temperature and therefore viscocity that the engine has been designed for.

Deanxm · Unread post by **Deanxm** » 17 Sep 2010, 17:09

Almost every new car ive driven needs the clutch depressed to start, and it is good pratice to do so on any car anyway.

D