afeldman327

Hey everyone, I haven't seen a thread on the issue I'm experiencing in 2nd gear.

There have been 2 phenomenons recently that I've noticed, and they both happen only I'm shifting into 2nd for the first time after startup. I am worried there's something wrong with the car.

1) After I start up, i shift into first, then into 2nd, but when I take my foot off the gas, the engine doesn't decellerate AT ALL. The rpm's don't drop and the car just keeps going at a steady rpm like it has a mind of its own. It was scary when this happened the first time, because sometimes I just lift off the gas when a car is coming and i want to slow down, instead of braking, but i almost hit a guy coming towards me the first time this happened. It only happens immediately after startup, and it seems as though after the car is warmed up it doesn't happen.

2) This morning in the same situation, (startup, 1st, 2nd) 2nd gear was "jerking" a lot. I shifted smoothly into 2nd, had the gear fully engaged, was steadily giving it more gas, and the car was jerking like crazy. It felt like the days when I was learning to drive stick and I wasn't giving enough gas and the car starts to choke. only this time I was giving it plenty of gas. Temperature outside was about 54, and as a sidenote I picked it up from the dealer yesterday for my first oil change/scheduled maintenance.

Anyone have any ideas on this? I'm not a mechanic. I do know that my car was M-flashed in case that comes up. and I baby this car like it's my first born child.

Thanks everyone.

Andy

hotpot

It's not abnormal.
When you first start the car cold, the engine will idle at a higher than normal rpm(I'd say between 1500-2000 rpm) until it's warmed up. That's why when you lift off the gas, it will not slow down, as the engine is running at 2000 rpm.

Genesis

Andy, how long have you been driving the car? I ask because I've only had my 6MT 8 for a couple of weeks and I'm still getting used to the clutch. From what you describe, there's no problem with your car, it's simply a matter to adapting to the low bite clutch.

afeldman327

I've had the car since July and have adapted to the clutch. This is the first time I have experienced these things, and it seemed like it started around the time the temperature started dropping.

GiN

It's absolutely normal.

The accelerated warmup system always seems to raise the rpm a bit higher and for a longer period of time during cold weather. In fact you won't even have to step on the gas pedal because the throttle motor is setting your rpm to around 2k.
If the car starts hopping and jerking right after you've gotten into gear it's probably because theres not enough torque at the moment to get the car going smoothly. A cold motor trying to drive in taller gears at low rpm increases the chances of this happening.

Genesis

Hmm, dunno then, what Hotpot describes is probably the issue.

penman

Yeah i've noticed idle/throttle does some stuff completely on it's own cold. I usually wait till it drops to steady 900 - 1100 before driving - takes about 5 minutes.

Genesis

Honestly? do you wait 5 min to warm up before driving? I treat my 6MT 8 like any other car...jump in, turn it on, and accelerate out. I'm perplexed about these warm ups.

army_rx8

you shouldn't drive the 8 right after to turn her on ( you shoudl wait fo rthe engine to reach it's operating temp)..well you should do that with every car but especially the 8. Heard of a few people having coolent leak into the engine..apparently the side and intermidate housings are two different metals (aluminum and iron) and they expand faster /slower than eachother. If you rev around befor sh ewarms up correctly the side housings will expand at a different rate to fast and you could mess up your seals. Granted that is a very extreme case and i've only heard of a few (like count them using no more than both hands). Just somethign to think about.

Oh and i think it says how long you should wait before moving the car once you turn in on in the manuel (12 sec. minumum for the ecu self test/ 5 min.'s fo rthe car to warm up)

Cheers

afeldman327

maybe i should just keep it in first gear longer and not shift into 2nd right away? I know we aren't supposed to drive it hard until after the engine is fully warmed up, but i haven't heard such issues about not driving at all until after the engine idles for 5 minutes. who has the time to sit in their car for 5 minutes before driving away? I don't think Mazda would have designed a car this way.

army_rx8

HEHE I do...gots to treat my baby right. B/c i sure do push her hard

hotpot

I drive off as soon as the engine is turned on. I just don't rev it above 4000 rpm until it is fully warmed up, although I'm not even sure if that's necessary.

downshift

Not when the average temperature over in Singapore is around 27C - 32C ! :D
As the weather gets colder, it's good to warm the engine up a bit before moving. I usually wait for the tach to stabilize at around 1100, which takes about a minute. The 5 minute wait probably applies to temperatures below freezing.

Genesis

You've got that right...it's warmed up even before I put the key in the ignition