I notice that during stop and go traffic when the car is in gear (1st), the car exhibits some sort of herky-jerky motion. I had to press the clutch to eliminate that... or go into neutral.
Could it be the motor mount? It's an 06 GT.

 

can also be coils going out

 

Why? If it's the coils shouldn't that be for all speeds?

 

hrmmmm is your car running rich? exhaust smell of gas?

 

Nope. Atleast not that I know off. I generally try to avoid sniffing the pipes while stuck on traffic.

 

If what you're describing is what I think it is, you're probably just not steady enough with the accelerator. It took me a few months to get used to driving at very slow speeds without partially riding the clutch (to avoid the "herky-jerky motion").

 

But I am not even on the accelerator. 1st gear coasting <10kph. If I tap on the accelerator it may jump and hit the car in front.

 

are you just lugging the engine?

 

Do you know what lugging engine means?

 

yeah, if you're not on the throttle then it isn't the coils.

At really low rpms the car can get bouncy back and forth. It sounds normal. Give it a little gas as it does this and you'll find it goes away.

 

Well that's what I've been doing. I like to know the cause of it. So it's not engine mount? sure?

 

your 8 is angry about being stuck in traffic and is complaining. It's totally normal. If you're verrry gentle about your throttle you can keep it from happening.

 

Yeah, I've found it can be jerky if you take your foot off the throttle abruptly in 1st or 2nd as the revs fall below 2000. Same if you abruptly apply throttle anywhere near idle in 1st or 2nd. I usually just ignore it (though it makes me wonder what other cars think ) or ride the clutch more.

 

Actually let me add; Any time that I'm slowing down (no gas) with the car in gear (1st, 2nd, and occasionally 3rd), the revs bounce and car jerks back and forth a few times as it gets close to idle. If I know that I'm going to be stopping I usually just push the clutch in and go to neutral to avoid it, but usually I'm just slowing down to match the traffic's speed. I've already had my motor mounts replaced and it still does it so I assume it's normal?

Is this what you're experiencing delhi?

 

Nope. There's no rev bounce. And it only occurs in 1st at crawl speeds. But once I get the clutch in or neutral - no herky jerky. My old 2.5RS has this issue as well. I wonder if it is the clutch....

 

sounds like something that happens to any manual transmission car, ease off the accelerator when you're coming to a stop and slowly ease into it when you are taking off when you are in 1st.