Cold start, rough idle every time?!?

1024M3 · #1 (**permalink**) 08-29-2003, 02:50 PM

Hey when I start my cold engine it runs really rough for about 20 or 30 seconds and then it smooth itself out to a purrrr. Is this normal? My wifes 328 makes a distinctly different sound when cold starting and then runs smooth. Mine is jerky though.
Only on cold starts....

mgd guy · #2 (**permalink**) 08-29-2003, 04:13 PM

get a tune-up. u prob need new plugs or wires...or a top engine cleaning to clean off the valves or mabey even an injector cleanig...

98whiteM3 · #3 (**permalink**) 08-31-2003, 09:38 AM

hey my car does the same. So a tune up is all it needs?

E31 · #4 (**permalink**) 08-31-2003, 04:33 PM

This is a common problem on the 8...the problem is a faulty intake manifold gasket. Be thankful you don't have an 8, the gaskets cost $600. What it does is that the IM gasket gets brittle and gets cracks, letting more air in. I have relaced them on my 8 and it has been perfect ever since. It could also be the O2 (oxygen)sensors, or as stated, the plugs.

From what you are describing, iti s the IM gaskets. After a bit, the heat from the engine expands the rubber and makes a better seal, that is why the problem goes away after a while.

98whiteM3 · #5 (**permalink**) 09-01-2003, 09:44 AM

how much do im gaskets cost for the M3 do you know offhand?