tonyjms2005

Hi
When the rx8 was new and being promoted, my local dealership claim to prove the rotary engine was so smooth they could put I glass of water on top of the engine and it wont move, of course while the engine was idling.

From what I have a seen with the rx8 I wouldn't want to try it lol.

Antony

RIWWP

iTrader: (2)

Yeah, no. There is still vibration. Just find an RX-8 with a collapsed motor mount and you will find plenty of 'unsmoothness'. The dealer was just feeding you some BS.

The engine is far smoother than piston engine cars at a given RPM, but that doesn't mean it is actually 100% smooth.

tonyjms2005

Fair enough, my idle is not too bad until you put on too many electrical loads. Also do you get a vibration around 1900 rpm?

Cheers

Antony

RIWWP

iTrader: (2)

If you get excessive vibration at idle WITHOUT the RPM needle dipping, then you probably need to replace your motor mounts.

Some low level background vibration will always be present, but it shouldn't be enough to rattle anything or bother you. Usually the highest point of vibration will be the shifter, since it has the most direct connection to the engine of anything you touch from the driver's seat. If it is visibly vibrating with a stable idle RPM, then it's probably motor mounts.

tonyjms2005

I have new oem mounts, but I think I have a vac leak I think it is running a little lean at idle to be honest.

I will have to build a smoke tester to find out, as I think it is the lower intake.

RIWWP

iTrader: (2)

Yeah, if you have something else messing with the idle stability, you need to fix that first before evaluating idle vibrations.

tonyjms2005

Just an update.

Today the weather was warmer, I drove the car with less than a quarter of a tank of fuel. After around 30 mins the car felt low on power, when I filled back up with fuel the problem seemed to reduce and then the car returned to normal after a short while.

Sounds like the fuel pump is on it way out?

Cheers

Antony

04Green

iTrader: (1)

Fuel Pump.

Yep, you got it right.

Now, you might be really interested in how much of a difference a fuel pump makes to to how the car run...

tonyjms2005

Yes I am quite looking forward to seeing what difference it will to the car overall. I will update once I have sorted it.
I am waiting for a new fuel tank ring to arrive as the one on it now is mega tight and I suspect it may break.