I was taking the car out to rent a movie, a short trip, so I didn't let the engine warm up, like I usually do. After a couple track-home streets, I got to a bigger street and accelerated quickly...but right about 6500 rpms, the car suddenly jerked and decelerated. I shifted gears, waited 'til the next street and accelerated more slowly, and it did the exact same thing.

I waited for the engine temp to get up to three bars, then tried accelerating up to the same rpms, and it was fine. But I know that I've gotten near the redline when the engine temp was at two bars before, so what's up with that?


Aside from that specific question, generally speaking, is it necessary to let your engine warm up before taking it out? How long should you let it idle on your driveway before driving?

Thanks!

 

S2k Newbie,

The VTEC system cannot actuate until enough oil pressure has been reached to activate the VTEC solenoid. Until the car is sufficiently warm, and there is enough oil pressure for the system to work, the ECU will induce an early fuel-cut. That's what you felt when the car jerked and decelerated.

In general, it's a bad idea to try to race around when the car is cold. It causes a significant amount of wear to many of the engine components. Not something you wanna do a lot of in a high-revving engine. A piston with stress fractures that grenades at 9000rpm is no fun to deal with.

In general, you don't need to let it idle much. In fact, it will take longer to warm up if you don't move it around. Just treat it gently while it's cold. It'll be warm enough for the happy fun stuff in just a couple minutes of normal driving.

Cheers,
Ben

 

Ahhh. Thanks a lot Ben.

 

Might want to wait about 3-5 minutes past three bars.......

Utah

 

Yeah, cause not only do you want to warm up your engine and its oil, but it's also very important to warm up your tranny before gunning it through VTEC -- 5 minutes of easy-to-moderate driving should do it.