cold bloodied V6

[mx3_ryder]

+1 on driving softly until engine reaches full operating temp. Full operating temperature before taking off, well I don't believe in that theory.
Full temp before going WOT, that I strongly believe in. I've owned many 2 stroke dirt bikes and snowmachines where cold engine seizure is a risk if not properly warmed up, so its naturally become a habit with all my toys and vehicles. I have one question at the moment for the Hei mod, can I use my original distributor cap to use w/ a power tower?

[Inodoro Pereyra]

I could easily start personally attacking like you're starting to, but I prefer to be civilized. No need to be a bunch of keyboard warriors here.

I'm not attacking you personally. If you felt my words were in some way intended as that, I apologize.
I was just stating, once again, my (by now, I should think well known) despise for that kind of misinformation you posted, unfortunately not for the first time.
Mechanics statements belong to mechanics' engineers, not to personal trainers, nor reporters. It's that simple.

BTW: NOBODY (except you, that is) ever said the engine should be warmed up for "extended periods". The engine should be warmed up until IT REACHES IT'S NORMAL OPERATING TEMPERATURE regardless of how long it takes. And, just FYI, an engine doesn't reach its N.O.T. when the coolant does. The engine reaches its N.O.T. when the EGT gets within operaing range. That is A LOT FASTER than it takes the coolant to warm up.
But then again, you may ask: "And how would I know when the EGT get's within the operating range, if I don't have an EGT meter in my car?"
Simple answer? Look at your tach. When the idle speed goes down from the 1200/1300 RPM range (the warmup range) to the normal 800/900 RPM range, you can drive. Simple, isn't it? Or, if you wanna do things right, you can GET and EGT meter. No meter is ever more helpful for tweaking an engine.

Prove me wrong.

Let me see if I can say this one more time (and they say I'm not a patiente man ), in the hope that this time you may get it:

I DO NOT NEED TO PROVE YOU WRONG. YOU stated that the proper warmup procedure used, supported and PROVEN by engineers all around the World for over a CENTURY is wrong. Therefore, IT IS YOU WHO HAS TO PROVE THEM WRONG, not me who has to prove you anything. Sorry, the burden of proof lies with YOU.

That said, I consider my goals on this thread fully accomplished:

1. I tried to help mx3_ryder with his issue. Turned out I wasn't that much help after all. However, he was able to figure out his problem on his own. Done.

2. Once you posted your misleading "information", I wanted to make sure no rookie that stumbled upon this thread followed that advise without looking for a reliable source, one way or another. Never feared mx3_ryder would follow such advise, because, having read plenty of his posts over time, I'm aware he knows way better. Done.

3. Gave you plenty of oppoirtunities to prove your point appropriately, which you carefully avoided, and tried to shift that responsibility on me. Done.

So, as far as I'm concerned, I'm done with this thread. I'm not gonna get into an endless discussion on something that's been proven over and over. I just don't have the energy for that anymore. If you want to start driving your car from the moment you turn the key, the more power to you. If somebody else, who's seen this thread, decides to do the same, they can't say they haven't been warned.

You have a great day.

[SuperK]

Doubt it's the VAF. If swapping it doesn't work then I say yeah maybe get a cheap second disty and if that solves it, start getting parts for the HEI mod then it should never happen.

A VAF problem would give you a CEL, so that's not it.

If this is the ZE, incorrect.
KL31 ECU won't show codes like a NA ECU.

VAF can cause bucking/surging, but generally it gets worse as you continue driving it, and generally isn't temperature related. It's definitely worth swapping if you have one available. Not recommended to overlook.
I agree with RX8SE3P, since the distributor is a known weak link, don't overlook that as well!

There are plenty of free troubleshooting steps you can take as well, like disconnecting hte o2 sensors and see if the engine reacts differently without them plugged in for example.


You can mod your existing distributor cap just fine. There should be some pics of where to drill the hole. It's super easy.

[mx3_ryder]

Yes, I run a kl31 ecu, but use my k8 ecu for checking codes. Only codes I have are for egr which we all know the J-spec ecu's don't use egr. I'm currently on my 5th distributor so its time to do the Hei and be done with all these spark issues I've been blessed with; past and current.

[Nd4SpdSe]

I'm alos a firm believer of letting the motor hit full operating temp before hitting WOT.

Most cars say they don't need to warm up nowadays, but especially with tigher tolerances, metals will expand as they warm up, and different parts of the engine will expand differently. The truck I will fire up and drive away, but will take it easy until she's up to temp, especially since she's boosted. In the winter I do like to wait a bit (minute or two maybe) to help, especially since the oil will be thicker so to give it a chance for a good amount to run through the motor. The Rx-8, I let the temp gauge start to register than I'll take off. She doesn't get winter driven.

[RX8SE3P]

Inodoro Pereyra-

I am trying to figure out if what you're saying now is that you don't wait until the engine coolant temp gauge reaches it's normal operating point. Rather you wait until the revs drop to 800-900 (is that your normal idle?). My normal idle once the engine is completely warm is 650-700. But yes it does get there quicker than the coolant guage reaches it's N.OT.


I am simply against the idea of idling the engine until the coolant temp gauge reaches it's N.O.T as that could take 15-20 minutes in very cold conditions and who does that honestly? It'd take forever to get anywhere in the cold weather.

[xrp861]

if you do not wait until your motor is up to normal operating temp it can cause big problems for you one day. also i am one of the very few apperantly that waits til my cars warmed up to drive it in cold weather because i am not a moron. not only can you not defrost windows without heat but the oil does not circulate properly due to being way thicker due to cold weather wich makes it harder for oil to reach where its supposed to go. ive seen someone i know spin rod bearings from doing this over a 3 year span in a brand new car and guess what it wasnt covered under warranty because it says in every operators manual to wait til vehicle is at operating temp in certain climates.

[Inodoro Pereyra]

Up until the combustion chambers (and especially the cylinder and piston heads) reach full operating temperature, if you step on the throttle, the extra fuel injected into the cylinder can have a(n over)cooling effect in the cylinder, and can cause some hesitation. That's normal of all engines, but especially of all aluminum engines, being that, due to aluminum's much better heat transfer ratio over iron, it takes longer for the engine to reach operating temperature, and more so in cold weather.
So, it's normal, don't worry about it. I'd strongly suggest you do a proper warm up before driving, though...

That above is my first post in this thread.
As you can see, there's not a single mention to the coolant or its temperature. What IS mentioned, is the combustion chamber temperature.
Cylinder walls are usually made of iron. As iron has a fairly poor heat transfer ratio, there's normally a noticeable temperature difference between the internal wall (the wall on which the piston is sliding) and the external one (the one in contact with the coolant). That, and the fact that the coolant also touches surfaces that are as cold as a corpse, means it will take a long time to warm up, if ever (I lived in Miami, so I didn't have that problem, but I can understand how somebody living in Vladivostok may see things differently ).
But it also means the internal cylinder wall (which is our REAL problem) will heat up much faster than the coolant.
The reason why we want the cylinder wall to heat up is simple: Iron heats up slower than aluminum. Add to that the fact that the cylinder walls reach a much lower temperature than the piston heads, and that aluminum's thermal expansion ratio is higher than iron's, and that compounds the problem greatly. That's why proper warm up is so important, especially on newer engines, which have much tighter gaps, due to environmental concerns.
Why? Because now that the aluminum piston is hot and the cylinder wall is cold, the piston/cylinder gap becomes tiny (since aluminum expands much faster than iron), and, since when you load an engine (I'm mentioning "LOAD", not "WOT". That myth that if you don't go WOT on a cold engine, everything is all right is idiotic) you increase the piston head temperature (the piston head is the only part of the cylinder that doesn't have a direct way of cooling itself), and so you run the risk of that gap "disappearing", and the engine seizing.

But "proper warm up procedure" doesn't mean waiting until the coolant is hot. That's like burning down a house to kill a fly.
Some engines (I don't remember the K series) have 2 coolant sensors: one for the gauges, and one for the ECU. The ECU one is on the BLOCK, not in the coolant stream. That sensor gives a (direct or indirect) reading of the combustion chamber temperature to the ECU. Besides that, the upstream oxygen sensor offers an EGT reading as well (some engines rely only on this reading, as the EGT is way more accurate than a block temp reading). Between them, the ECU has a very accurate way to know when the engine has reached its NOT, and it's ready to receive the normal air/fuel ratio to work. That's the moment when the ECU drops the engine RPM, and that's the moment when you can drive the car.

About the RPM ranges I mentioned, I wasn't talking specifically about the K. I haven't had a car for the last 4 years, so I don't remember much data specific to a given engine. Sorry for the misunderstanding...

[xrp861]

actually on the kl and k8 they are both in stream right by the coolant fill cap. most are in or around the same spot the ect is never in the block and niether is the one for the gauges. at least on the hundres of cars ive repaired.

[davmac]

Inodoro was referencing Exhaust Gas Temperature (EGT) not Engine Coolant Temperature. EGT is directly related to the air / fuel ratio. A rich air fuel ratio (more fuel then necessary like you have just after starting a cold engine) will show lower EGT. Eventually the EGT rises as ideal air fuel ratio is reached and (as is being argued here) it is "safe" to drive the car.

This whole thing is way off topic. To the OP: I also experience some hesitation before the engine is completely warmed up. I guess that also means that I don't usually wait for the engine to completely warm up before driving. I'm in the camp of letting the engine run 1 - 2 minutes at idle and then driving gently for the first few miles.

[mitmaks]

If this board wasn't slow I'd lock this topic long time ago. But it's entertaining to see how many opinions are out there so i'll let it run until everyone looses interest in it. Personally I don't wait whole lot for engine to warm up until I drive, I start it, by the time I buckle up and release ebrake and put it in gear the oil pressure is up to lubricate entire engine. If you're so worried about engine lubrication/warm up in winter run thinner/synthetic oil.

[RX8SE3P]

Lol apologies on thread hijack mitmaks!

Inodoro Pereyra - Thanks for clarifying. Agreed on load too, I would never load the engine cold. I honestly though you were talking about warming the engine up until the coolant temp gauge reached it's normal operating temp

I have no issues with your explanation on warm up, makes sense and I probably do it your way more often than not

[Inodoro Pereyra]

You're very welcome, sir.

Actually, albeit off topic, this discussion may end up being constructive after all. All these years, I never realized people had a different understanding of what a "proper warm up procedure" was. I always assumed everybody knew the difference...

Coolant temperature is a very inaccurate way to determine engine warmup, at any outside temperature. There is, also, the argument (I guess, valid, if the circumstances justify it) of not starting to drive in very cold weather until you can defrost/defog your windshield, but, if we consider ONLY the engine "well being", the best way to determine when to start driving is by monitoring the EGT (Exhaust Gas Temperature - Thanks Davmac).
The relation between the EGT and the combustion chamber temperature is twofold (not sure if that's the approppriate word to use here): First, EGT will start to slowly raise as the combustion chamber temperature raises (just because the exhaust gases are spending less and less energy to heat up the metal), and second, as Davmac said, once the EGT reaches a pre established threshold, the computer will switch maps, and lean out the mixture, so the EGT will rise more or less sharply.
Besides, monitoring the EGT is so damn cheap (you don't even need a sensor: you just hook up the temp gauge to the oxygen sensor) that it's really a shame to not get such a wonderful tool, especially if you're planning on tweaking the engine.

Either way, if you don't want to put an EGT meter in your dashboard (for whatever reason), keeping an eye on your tach is just as accurate.

So, I guess we were both saying the same, then.