Cold Wheather Warm-up
#11
01-11-2007, 07:27 PM
RE: Cold Wheather Warm-up
I personally let mine warm until it idles down. On a related note, the shift point on my automatic increases significantly when the engine is cold. It stays in 1st until @2500-3000 rpm. until it warms up. Then shifts normally. Is the Tip programmed this way, or am I having an issue that needs to be looked at? I haven't tried shifting it into 2nd with the Tip yet, assuming it was the tranny's way of helping the engine warm more quickly, or the tranny's way of warming itself up.
#12
01-12-2007, 07:35 AM
RE: Cold Wheather Warm-up
Could be programmed that way. The 3rd generation RX7s had a cold-start program that made the ECU raise the idle speed to 3000RPM for awhile upon cold start, to help get everything up to temperature faster. I assume that they did this to help light off the cats sooner to decrease cold-start emissions (since the rotaries are known to be so dirty), but before I digress too much, my point was that some OEMs do program in higher RPM when cold for various reasons.
#13
01-12-2007, 08:38 AM
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RE: Cold Wheather Warm-up
ORIGINAL: duburban
confused AWDaholic. what invisible link?
confused AWDaholic. what invisible link?
ORIGINAL: duburban
any of you guys use this lucas oil product, to avoid "dry start-up"?
any of you guys use this lucas oil product, to avoid "dry start-up"?
#16
01-13-2007, 05:57 AM
RE: Cold Wheather Warm-up
ORIGINAL: AWDaholic
Well, since it's an aluminum block, you don't wanna "shock" it by NAILING the throttle with a cold engine, obviously. Sooner or later you'll crack the block and then you're well and truely F'd.
Personally, I let it pull itself off, under its' own torque, for as long as that is practical. Entering a traffic stream, for instance. Even then, I try my best to keep the rpm as low as I can get away with until: 1) The heater starts pumping heat out of teh vents, which is generally accompanied by: 2) the temp guage has reached the bottom line indicator, on the scale. Once I notice either (or both) of those I assume the oil is sufficiently heated to allow it to flow into all the nooks and crannies it needs to reach. I've used this technique for teh better part of two decades; long before conventional wisdom held that sitting and idling is BAD; and, to the best of MY knowledge, have never had any cracked blocks OR adversely contributed to Global-Warming any more than the average motorhead
Well, since it's an aluminum block, you don't wanna "shock" it by NAILING the throttle with a cold engine, obviously. Sooner or later you'll crack the block and then you're well and truely F'd.
Personally, I let it pull itself off, under its' own torque, for as long as that is practical. Entering a traffic stream, for instance. Even then, I try my best to keep the rpm as low as I can get away with until: 1) The heater starts pumping heat out of teh vents, which is generally accompanied by: 2) the temp guage has reached the bottom line indicator, on the scale. Once I notice either (or both) of those I assume the oil is sufficiently heated to allow it to flow into all the nooks and crannies it needs to reach. I've used this technique for teh better part of two decades; long before conventional wisdom held that sitting and idling is BAD; and, to the best of MY knowledge, have never had any cracked blocks OR adversely contributed to Global-Warming any more than the average motorhead
#17
01-15-2007, 03:02 AM
RE: Cold Wheather Warm-up
ORIGINAL: GeilKyle2
Idleing equals cold incomplete combustion, leads to carbon buildup, scoring of cylinder walls.
Idleing equals cold incomplete combustion, leads to carbon buildup, scoring of cylinder walls.
The reason it is 'ineeficient' to let your car idle is largely due to your rings. Your rings are designed with twist such that they seal best under load (pressure). When you are idling, you have the least amount of cylinder pressure and your rings don't do their job, and you increase both crevice volume and oil consuption.
I don't know the physics behind the rest of the engine, except that I relate it to your body - before you get warmed up and blood pumping, you are stiff and slow...thus your oil is cold and less viscous... I usually baby the crap out of my car in the morning until just like others said, your oil temps start recording. I'd like to learn more about the subject...
#18
01-15-2007, 06:52 AM
RE: Cold Wheather Warm-up
I let my truck warm up for at least 5 mins... its best to warm them up IMO but for some reason I read that with Audi's it wasnt nessicary at all infact it was harder on the car to let it sit and warm than just drive it
#19
01-15-2007, 06:56 PM
RE: Cold Wheather Warm-up
Mine is always in the garage when it's not being driven but in cold Toronto weather I usually just hop in and am light on the throttle until I see that the engine and oil temps have risen. No adverse effects yet with that method using a variety of cars.
I have experienced that the gearbox holds a high RPM longer when cold than when hot. I assumed it was programmed that way as my Audi is not the only one that does it.
I have experienced that the gearbox holds a high RPM longer when cold than when hot. I assumed it was programmed that way as my Audi is not the only one that does it.
#20
01-16-2007, 02:40 PM
