Thinking tune up..what do you say

[ranger13]

I got a 1995 525i 5 weeks back, everything looked great on the test drive. From last 2 weeks I noticed some changes in idling and also lack of power at pick up.

Now it idles at around 900 but drops down to 600-700 range once I put it in the 1st gear. Occasionally it idles to 700 by itself. A couple of times the rpm shot to 2500 at starting on a hot engine. I just stopped and started again, after a couple of times it came back to 900 range. It never did this on a colder engine.

It runs perfect in every gear and speed. The only problem seems to be the idling rpm and lack of power especially in the lower gears. I dont notice any change in power at higher speeds.

Also it takes a little longer to start, but it never fails to start ....even in colder temps. I am going to change the spark plugs and see if it does anything. More than anything this made me thik about spark plugs.

I was also told by my local dealership to change my cylinder head gasket. I am planning to get this done later unless it has anything to do with the problem.

I read some backposts about fuel pump etc. Can anyone suggest if this is a tune up or fuel pump or anything else.

[bbig119]

I'm replacing my fuel pump this weekend so symptoms not unlike those you describe.

My rpms vary greatly at idle and will usually stall out at some point. The car becomes unresponsive to throttle and will take longer to start, especially after a stall. When I get the car to pull away from a stop it frequently jerks and bucks at slower speeds until I get it up to about 3000rpm and it will smooth out until I have to slow down and stop again. Temp of engine doesn't seem to make a difference. Temp of air doesn't seem to make a difference. I've tested around and fuel pump is top of my list.

There are a few things you can do to test the fuel pump. How many miles does the car have and do you have any knowledge about whether it has been replaced once before or if its still the original?

[Russell]

Previous records? do they indicate when the plugs were changed last? Every 30,000 is recommended. Also I think the dealership meant the "valve cover" gasket. They can leak oil on the spark plugs. I would replace the valve cover gasket set and plugs at the same time. Are you aware your car has 6 individual coils?

Advice.
Get previous records. Track down from previous owner, dealer who sold you the car, BMWNA etc. You need to set you your own mantenance schedule.
Buy a Bentley manual so you can do some things on car yourself
Get an owners manual if you do not have one.
Find a good local independent BMW mechanic.

[Ross]

Look first for vaccuum leaks, then idle control valve. None of this matters much if you need a head gasket though as the poor idle is the least of your worries.