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-   -   prpoper rx7 warm up!!! (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/prpoper-rx7-warm-up-61253/)

MCLELLANRX7 03-12-02 11:05 AM

prpoper rx7 warm up!!!
 
hey guys i just wanted to know if this was normal with the rx7???
ok when i first start it in the morning or when it has been sitting for a while,the rpm will go up to about 3k for 3-8 seconds then drop to 1500 and the temp will rise to the normal range in about 3-5 minutes is that normal for the temp to rise that fast????
thanks for the help

Cwaters 03-12-02 11:20 AM

yeah,
motors like to operate in their optimal tempature range so car makers install the thermostat inline to bypass the cooling radiator while the motor warms up. When the water reaches a certain temp. the thermostat opens up and you start to use the radiator keep the thing from melting down.

Cory

AKABILLY 03-12-02 11:24 AM

Warm up
 
My 7 does the same warm up cycle up to 3k RPM than down to 1k and finally down to 500 (should be 750) But my car takes like 7-8 minutes to warm up to normal operating temp or at least a half mile of driving to bring it up to temp @ 50 degrees outside temperature. Don't know if this is normal but that is what my car does.

tIIforever 03-12-02 12:00 PM

mine goes downfrom 2500 after the 3000 nice and smooth

xiaomingming50 03-12-02 12:31 PM

the 3k rpm thing was done so that it would heat up the exhaust systems faster so that rexies could get better emissions, this is bad for your turbos and somewhat bad for n/a as well
try to blip the throttle as soon as you start to get the rpm's down, that or start the car in gear, i've heard that works too
as for rpms dropping, it takes me a lot of driving before my car ever hits the normal 800 rpm, so i wouldn't worry about that
but screw sitting there while it idles, just drive it softly while its warming up
you'll waste less gas, and also i read somewhere that gasoline removes oil from metals, so with the rich fuel mixture at idle, you're probably causing the engine more friction than it needs

menace 03-12-02 06:24 PM


Originally posted by xiaomingming50
the 3k rpm thing was done so that it would heat up the exhaust systems faster so that rexies could get better emissions, this is bad for your turbos and somewhat bad for n/a as well
try to blip the throttle as soon as you start to get the rpm's down, that or start the car in gear, i've heard that works too
as for rpms dropping, it takes me a lot of driving before my car ever hits the normal 800 rpm, so i wouldn't worry about that
but screw sitting there while it idles, just drive it softly while its warming up
you'll waste less gas, and also i read somewhere that gasoline removes oil from metals, so with the rich fuel mixture at idle, you're probably causing the engine more friction than it needs

does anyone else do this as well or is it just him?

(ps. is his logic sound?)

CanadianRX7 03-12-02 07:19 PM

blipping the throtle doesnt do nething on my car when its at 3grand. Just wait the couple seconds it takes. It does it for a reason and im sure its not harmful to our car. Its way better then doing what he does (driving it when its cold).

Taranis 03-12-02 08:58 PM

I used to blip the throttle too at startup. It would come down to 1500 after that then slowly down to a normal idle.

Now, it doesn't do any warmup idle at all and I've been trying to figure out why. It just runs really rough while it's warming up at 850RPM.

- JB

von 03-12-02 09:49 PM

Well sounds like your running to rich Taranis. Faullty fuel injectors mabey? When I was running bad S-AFC setup with rich setting and miss connection I would not get the normal warm up. It would just idle low and shity.
Canaidian. Its actually common sense to warm up the car as fast as u can by driving it under 3k when cold. Wait a few secs for the oil to pump but dont just sit thier for 5 minutes.

CanadianRX7 03-12-02 10:12 PM

really?? well how is driving under 3k better then letting idle at 3k and then it goes down to 1500 and then down below a grand.
i let mine sit for 5 mins before i go to school and if u press on the gas when the car is cold is sounds and feels like pure shit.

Taranis 03-13-02 12:15 AM

I'm not quite sure what it is. It was doing the warm up idle fine on every startup, then once in awhile, now not at all. I suspect electrical gremlins are at work.

Dunno if this helps, but it idles fine (if a bit rough) as soon as it's warmed up.

Come to think of it, after it's been highway driven for about 45 min, the idle is back to rough again. Hmmmmm.... any ideas? How long do injectors last in these motors using good gas? (87 octane @ Chevron)

- JB

Grimlock 03-13-02 08:53 AM

start it in gear
 
i start my rexy in gear and it elimantes the cold start up. 3,000 rpms on a motor thats been sitting all night, thats nuts man. by starting it in gear my car stays at 1200 rpms and drops as it warms up.

Amur_ 03-13-02 09:53 AM

It isn't starting it in gear that bypasses the 3k warm-up, per se. It's starting your RX-7 with the clutch in.

I *always* let my NA FC warm up to operating temp before going anywhere. And she idles smoothly all the way. Having a remote starter means that I can often do this without freezing my cookies off. :)

I've always subscribed to the theory that driving off with a cold engine is a BAD THING. :dunce:

>>Now, it doesn't do any warmup idle at all and I've been trying to figure out why. It just runs really rough while it's warming up at 850RPM.

A rough idle often suggests a vacuum leak. Also, how long has it been since your car's had a check up? There are separate adjusters for the idle and maybe they just need some tweaking. :)

>>blipping the throtle doesnt do nething on my car when its at 3grand.
Mine, neither. Once she's up, she's up 'til she's done. :)

>>i read somewhere that gasoline removes oil from metals, so with the rich fuel mixture at idle, you're probably causing the engine more friction than it needs

Don't quote me on this, but I think that you're just splitting hairs here. Of course gas is going remove oil. It's a *solvent*. But we have our nifty OMP continually spraying oil on the rotors. Whatever the gas is taking away, the OMP is putting right back. :) And I doubt that the increase in gas in the Cold mixture would have such harsh results.

ttyl,
Amur_

http://www.chronicsite.com/gatchaman/images/Ken.gif

spankenstein 03-13-02 11:07 AM

I don't know too terribly much about rotaries and cold starts but with piston engines the general consensus that I've seen has been to let the car idle for 15 seconds to a minute then drive gently until it gets to normal operating temp.

The wait is so the oil can start flowing and the gentle driving is to get it up to normal temperature as fast as possible. I let my Focus sit for a few seconds and then keep my foot out of it and the revs under 3k, until the temp needle is in the middle then drive it like you stole it ;)

There also seems to be a lot of unsubstantiated "voodoo" associated with the rotary. It seems weird that there are a lot of subjects that have 100s of different, disagreeing answers (6-ports being a good example).

MaxRX7 03-13-02 11:21 AM

Just take off after starting the engine...

smith88 03-13-02 11:44 AM

I normally let my car idle for a minute or 2 when it's cold, but it still doesn't warm up fully until I drive about 2 miles. Might be my mods though.

If I get on the turbo before it is fully warmed up, I end up letting out a big Smoke trail. Does anyone else's car do this??

Grimlock 03-13-02 03:32 PM

yo amur
 
phat pic in your sig. i love that cartoon (G-FORCE) right?

jeff_oner 03-13-02 03:43 PM

when I dont have to be anywhere, I start my car and smoke a cigarette, by the time I am done with my smoke the car is fairly warm, then I drive it keeping below 3500 rpm then after the temp is normal for about 5 minutes or so I drive it like it wants to be driven.:)

Turblown 03-13-02 03:50 PM

my car used to do it, and i would tap the gas and it would go down to about 1500 and stay there for like couple minutes. I just did the TB mod and now it doesn't do it at all, i always warm up my car, and i think its bad to drive it below operating temp

Amur_ 03-13-02 04:22 PM

>>phat pic in your sig. i love that cartoon (G-FORCE) right?

Yup. Battle of the Planets for us Old Pharts. ;) Which is out on VHS and DVD now, btw.

- end shameless plug -

I still say that it's a bad call to move the car before the temp's up to norm. Like not stretching before starting a run at a track meet - your engine needs a chance to stretch its legs and get itself up and ready to go...

ttyl,
Amur_

http://www.chronicsite.com/gatchaman/images/Ken.gif

tmak26b 03-13-02 05:07 PM

I never wait 10 min to warm my car up, it runs

gotorx7 03-13-02 07:06 PM

I compromise :)

I let my 7's idle for about a minute, and then drive them gently (off the Turbo) until the guage hits operating temperature.

And the reverse procedure for shutdown.


My RX-7's

ponykiller 03-13-02 08:05 PM

The 3K start up is disengaged by the computer if the outside temp, along with engine temp, is too cold (<35F, I think). Do not let your car do the 3K warmup. It is for emissions purposes only, and is adding unecesary wear to the engine. Either start your car in gear or blip the throttle as the rpms climb to 3K, to stop the activated warm up.
I always let my car warm all the way up, before I start driving. Driving a rotary engine while it is cold can rip off an apex seal in the exhaust port. Do NOT drive your cars cold, especially turbos!!!

Kris

NZConvertible 03-13-02 08:19 PM

The 3K idle at start-up is a feature of US-spec cars only (and maybe Canada?), just like the pre-cat, EGR valve and some other emissions related bits. It is to bring the cats up to light-off temp as quickly as possible to reduce emissions during warm-up, when the engine produces lots more crap than when warm.

darkwaveboi 03-14-02 10:29 PM

so if you converted to jspec and got a jspec ecu, some of your emissions controls would just 'not' work?


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