FSS indicator on my C230 moved upward three times in 4 weeks. First it went from 5900 to 6900 miles then it went from 6700 to 7200 miles and this morning it went from 6800 to 8000 miles. I had the car for about 6 months and first 5 months it moved downward in the increment of 100 miles (very steady). Now I am at the interval of about 14,000 miles (injcrease from 11,000 miles to 14,000 miles within 4 weeks) for first service A. I talked with service advisor and he thinks it is normal. What do you think? Is it normal to to this? How often FSS calculate the intervals? Please let me know any feedback. I have about 5900 miles on my car so far.

 

No, that's not normal. The FSS will always count down (or hold steady) as long as the vehicle is being used and no service (including oil change) has been performed in between FSS recommended intervals. They way you described it, my guess is that the sensor or associated electronics has gone bad. Your SA probably needs a FSS in his/her system to advice you it'soperating OK. Check the section of the manual that deals with the FSS and refer your SA to that section. Insist that it's not functioning properly and that it should at least be checked. It's still under warranty so there should be no charge.

BTW, the FSS computation is done constantly - I don't know what the sampling rate is, but it doesn't wait to do the check. As soon as your ignition is ON, it goes to work.

 

It's normal for the service interval to increase, depending on how the car is driven. If you start to drive the car more frequently, and on longer trips, it will increase the service interval accordingly. Most first services occur between the 10,000-15,000 mile range.
Also, the FSS is working even with the car off, because it calculates the number of days since the last service, in addition to the distance covered.

 

Thanks MBTECH208

Thats exactly what happened. I hardly drove the car during month of December due to company shutdown/holidays and I started drive quite a bit more starting January.

 

I don't put too much faith into the FSS. I did an oil and filter change with 5000 miles to go and the interval increased only a little bit.

I don't plan on following it anymore anyway since my dealer said they will do the free A or B service under warranty if has been a year since the last one or at 10k intervals on the odometer, whichever comes first. I guess they could be a little gunshy after the class action suit.

They can check the MB computer database and tell when the last service was done even though I had taken the car to to another dealer before.

 

mbtech208

This morning my FSS went up by another 500 miles. Now I am at about 14,700 miles for the interval for the first service A. This is about 4000 miles increase since 1/1/2003. I know I am still within the limit (10,000 - 15,000) however this is a very big jump in fairly short time period. Is this normal?

 

Why care about it. If your dealer will do the A and B services every 10,000 miles as per warranty, let them do it.

You don't get a prize for going the longest interval.

 

Officially, warranty only pays for a service if the car is within 1000 remaining until the next service. Any earlier and the customer is supposed to pay for it. I've never seen that rule enforced though.

 

I took my clk in for something else and the service advisor said he would do a B service under warranty.

It was 9 months since the last A and the FSS showed over 3000 miles to go, but since I had 21k on the car it qualified for the 10k interval.

Just ask your dealer about their policy on doing the A and B services. The MB warranty department doesn't know what your FSS is reading anyway so if the dealer wants to do it, let him.

The synthetic and over 8 quart oil capacity helps for extended interval changes, but why take a chance?