I read many post and some say during cold start up, the FD needs about the 3 min warm up. Now does that matter what the temperature is outside, hot or cold. I read another post somewhere they say 30 sec warm up is good enough as long as you dont boost until motor is warm. Im trying to save as much gas as possible, killing my wallet and also environmentally friendly.

 

If you want to be environmentally friendly, don't drive your FD. :P

Personally, I let the car warm up for about a minute or so, then start driving off boost. I don't really start getting into the boost until I see temps over 70*C on the PFC Commander.

 

I start my FD than get ready to go where ever... I generally let it idle for about 10 minutes... than drive off boost until it fully warms up, about 90degrees...

 

30 seconds is more than enough. Just drive it easy until it is warm. Letting it sit at idle is pointless.

 

A little much don't you think??? A min and then drive off boost is more than enough.

 

1 min then offboost till 80 on powerfc for me. Its easy for me cos its straight onto the highway for a few k's. I'd hate to live in the hills and have to try warming it up without hitting boost.

 

I get in, start it up, and drive off. Of course staying out of the boost until the car is warm like everyone has been saying.

 

You want to get the car up to normal operating temperature without excessive idling, and you don't want to get into serious boost until the car is at normal operating temperature. I start the car and don't drive off until the car settles down to normal idle. Then I drive off easy not going over 4,000 rpm until the water temp gauge reaches its normal position.

I'm also assuming you know how to avoid the accelerated warmup cycle which shoots the engine up to 2,000+ rpm's when you start the engine cold. This is rough on the motor and was done to meet an EPA mandate. To avoid it, put in the clutch, put the car in gear, turn the key, then shift the car back to neutral when the engine gets going. The car will start at a lower rpm. Give it a few seconds to settle down to normal idle before driving off. You car will live a happier life if you follow these steps.

 

I always let my car warm up to operating temp before driving. But i do that with all my cars. I have also put in the aftermarket pellet that allows oil to flow during warmup so it's not harmful to my motor.

I've seen an FB's rotor housings that had the edges chip out on the compression cycle which caused the motor to lose it's power with any type of load. I suspect it was caused by many cold starts and no warm ups.

I just see it best to be fully warmed before driven so temps rise equally and slowly. Especially since our motors have crucial parts made of different metals.

 

I did an experiment with my daily driver for fuel economy. The first test would be to start the car up and go. The next was to let the car idle for 5-10's and then go. With both of these tests recorded the mileage till 1/4 and then recorded the amount of fuel my car took in. With those two variables I could then come to an average. To my surprise the idling car received better fuel economy.

As for the rx7 even if it wasted fuel it's no matter as the motor having warm oil to lubricate is more important IMO. Regardless most rx7's get poor fuel economy... Protect the motor!

 

I start it, buckle my seatbelts, etc., and drive off. I just drive gently until it's reasonably warmed up (time depends on how cold the engine and the ambient are). I've done this for over 15 years and 57K miles on my FD, and have had no problems.

In general, idling to warm up a car engine wastes fuel and may even hasten wear, since washing down the seals with excess fuel due to the rich idle mixture just after startup can't be good. Also, the longer it takes to warm the engine, the more water condensation is allowed to enter the crankcase, possibly leading to sludge formation.

 

Start her up and let her idle up to 3k then when she hits 1500 just drive softly until shes warmed up fully. (Generally about 5-10 minutes @ 65mph on a 70F day)

Softly is just keeping her out of boost as much as possible.

 

wow...I hardly ever hit 90 anything on the pfc!

 

Exactly, this is also how excessive carbon build-up happens. Cold starts have a pig rich A/F mixture. Long periods of idling don't help burn the excessive gas much. That's why I start my car, let the AWS feature do it's thing, then drive off.

 

I recently read somewhere that warmup is not necessary and has no benefit in an FD, just don't get into heavy boost until normal engine temp is reached. Can't remember where I read it, but I'll see if I can dig it up again.

 

If you warm the engine up to temperature by idling it before driving it, the engine is up to temperature - however the rest of the driveline is not, so your diff and gearbox is still cold. This can mean if you see it like "oh man im all ready to go boost onnnn" you are putting quite a bit of strain on the rest of the mechanicals.

just something to think about.

+1 for the start it up, wait for 30 seconds or so, and then drive gently till up to temp.

 

Start and drive -just keep the rpms down until the oil gets warm.

 

That's hardly a scientific way to measure gas mileage. There are way too many other variables, like where you drove, temperatures etc etc. In addition to that, measuring fuel consumption with the fuel gauge is completely inaccurate.

There is no way you are using less fuel by warming it up before driving. No way!!!!

 

totally agreed!!!

 

Exactly. Your engine will get to operating temp far quicker driving mellow than sitting there idling, and the more time it spends on the pig-rich cold start maps, the more excess fuel is washing away any lubrication still on the housing walls. At least when you're driving the car under light throttle, there's some oil being injected into the combustion chambers.
Actually, I think what you mean is the longer you take to warm up the engine, the more chance there is for sulfuric acid (water condensation still in the crankcase mixing with sulfur compounds in the motor oil resulting from combustion blowby) to form in the crankcase, which is obviously bad for the internals.
Condensation forms overnight in a cold engine. Once you begin warming up the engine (and motor oil), the condensation begins to boil off. This is why numerous little 2-minute trips to the corner store (where the oil can't get up to operating temps high enough to boil off the condensation that inevitably forms in the crankcase overnight) are bad for your engine.
Sludge is the result of contaminants from over-stressed motor oil mixing with various by-products of combustion over time.

 

While driving without any 02 reference you're going to run rich. Both of these tests were done on the same route back and forth to work. I knew someone who let their car idle in my driveway overnight. Come morning time the car was still running. They were surprised as they only used 1/8 tank of fuel. Idling does not burn as much fuel as you guys think...

 

Was the EPA mandate only a US thing...ie do JDM models also have the accelerated warm up function or not??

 

As others have said, I start the car let it run for a minute then drive off staying off boost. When it gets to 85C I hit the gas

 

US only...

And I always let my car idle to operating temps before driving, be it a trip to the corner store or to the next state. Back when I let it idle for thirty seconds and drove, the oil pressure was through the roof. And just because your water temps are at operating temps, does not mean that your oil temps are...

 

3 min is more than enough.

For me, i say i let it run about 5 mins +.

I start the car
Put car cover away
Clean all windows with windex
Open my front gate
Roll car down driveway past front gate
Get out to close front gate

I say that totals to about 5-7 minutes. I get in the car to drive off and its about 110F on the temp gauge, especially now since the weather is still warm.