I have this knocking sound at idle when I start my car. It completely vanishes after one minute or I drive the car a short distance.. Any ideas? my oil level is fine..

2003mc 73k

 

Need more info:

Do you have an oil pressure gauge?

Is it a tap or a deep knock?

Have you raised the bonnet and listened more critically to determine what part of the engine or other areas the noise is coming from?

Try this. Raise bonnet. Pull each spark plug wire off and put them back on, but don't worry about the valve cover seal. This is just to loosen them up.

Have someone start the car. While wearing insulating gloves, or using rubber handle pliers, remove one spark plug wire at a time and listen for a change in the knock sound. Do all four wires one at a time.

When finished, turn off engine, and properly refit the wires to the spark plugs.

Then report back to us.

YD

 

The gloves part is important... I got arced a while back when just wiggling the wires while running.... Owwwww....

 

the sound is more of a tap. I dont have a oil pressure gauge but i will try the spark plug thing today. I dont have any insulating gloves but I do have some nice rubber pliers.

 

Metallic tap or plastic-sounding tap?

I have an intermittent plastic tap I'm trying to track down.

 

I have a tapping noise, maybe similar: occasionally, while idling after cold start, my MINI sounds like someone's lightly rapping a knuckle on a heavy plastic box; goes away after a minute or so of driving (I've always let my vehicles idle for a minute or two before driving 'cold') - noise is regular, speeds up with engine speed - happens winter or summer - hard to track down source with the extra noise from CAI, etc...

 

almost sounds like a gurgling sound when I start the car - lasts for about 2-3 miles - noticeable when idling, thought it might be the a/c condenser, but still occurs if I turn it off.

 

The gurgling sound is a symptom of low coolant. Mine did that when I had a leaking thermostat housing. You may want to check the coolant level..

 

thanks - I just looked and it is absolutely below the min level.

two questions:
what kind of coolant do I need - BMW / any kind / just water?
if it is low, does that mean the there is definitely a leak?

Thanks!

 

I did not use the BMW/MINI coolant. I added Prestone all makes all models 50/50 coolant.

Don't know if you have a leak, but your coolant is going somewhere. A leaking thermostat housing is a very common problem. What year is your MINI? If you are still under warranty go to the dealer.

 

I have a 2005 MCS - only 40k on it, but no longer under warranty. Do you think that I should just add some coolant and keep an eye on it?

 

Well for the time being I think that would work. It will give you an idea on home much & how fast you are losing coolant. The leak is not very likely to get better on it's own. You must keep an eye on it, over heating your MINI can end up costing much more that the leaks repair would cost.