How to tell when spark plugs were previously done?

[mikemulkern96]

E93 M3 I bought the car with 58,000 miles on the clock, now it's got 65. The dealership claimed great regular maintenance but never provided a history report. Would this information be in the carfax? Should I call up the dealership? Any chance theres a fellow Blue Driver owner that can tell me how to use the tool to view something helpful? Thanks folks.

[kevin @ eas]

Other than the dealer report no real way to really tell. You can pull the plugs out and take a look but at that point might as well replace them. Dont think car fax will show what specifically was done.

[roastbeef]

Replace. My dealer tried to tell me they wouldn't do sparkys at 37k because the car didn't ask for them as part of the CBS system in idrive.
30k may even be too long of an interval depending on your driving habits.

[Dpc2u]

My carfax reflected the plugs being changed at the dealer at 35,000 miles as well as all oil services, brakes and other checks. It also showed tire replacement at a European repair facility just before I got it. I think it is hit or miss though based on the info entered and whether the shop participates in the data recording.

[randrews15]

I'd go ahead and replace them. If it's not on the Carfax or some other receipt, then they were never done and probably need to be replaced. It's an easy DYI that you can do if you take your time and gather the necessary tools. Plus you can look at the plenum gaskets and make sure they are still in good condition. I replaced my plenum gaskets since the plenum never sat right with the old ones when I bought the car. Once done the plenum sits perfectly. It's a cheap PM that can't hurt to do.

[StripclubDJ]

The best way to tell if they have replaced IMO, is to replace them yourself

[dparm]

Originally Posted by kevin @ eas

Other than the dealer report no real way to really tell. You can pull the plugs out and take a look but at that point might as well replace them. Dont think car fax will show what specifically was done.

Pretty much this.

Replace roughly every 37k. Unless the car is at the race track all the time, I don't see a need to do it more often.

[pbonsalb]

The gaps on my plugs had significantly opened in 30k miles.

[kyrix1st]

By replacing them.

[pbonsalb]

As they wear, the center electrode becomes oval. If yours look perfectly round and you can’t spend the $80 on new plugs, the risk is low there will be problems if you leave them. If you can see an oval shape, I’d definitely replace them.

[kyrix1st]

Originally Posted by pbonsalb

As they wear, the center electrode becomes oval. If yours look perfectly round and you can’t spend the $80 on new plugs, the risk is low there will be problems if you leave them. If you can see an oval shape, I’d definitely replace them.

Is that what initially caused my car to run like it's low on compression?

My 3rd gear pull was much better right after I changed the plugs, but kind of back to being weak after around 5000 km. I do track my car though.

Have also been told that Ceratec might gunk up the plugs..

[pbonsalb]

I doubt you have enough plug wear at 5000km to make a difference you can feel. I’d guess your problem is something else. I think these motors are heat sensitive and pull timing. Could also be fuel related timing pull. Ceratec goes in the oil not the gas tank so that should not affect the plugs unless your rings or valve stem seals are bad.

[IanMan]

Just replace them. It's inexpensive and with a car like this, you shouldn't skimp out on preventative maintenance if you want to continue enjoying it.

[kyrix1st]

Originally Posted by pbonsalb

I doubt you have enough plug wear at 5000km to make a difference you can feel. I’d guess your problem is something else. I think these motors are heat sensitive and pull timing. Could also be fuel related timing pull. Ceratec goes in the oil not the gas tank so that should not affect the plugs unless your rings or valve stem seals are bad.

The car does not respond to my throttle input if I floor it under 3000 rpm in 3rd gear. 4th gear pulls right from the bottom no problem.

If I rev out each gear it pulls hard.. the symptoms were a lot better but still present when I momentarily put my catalyzers back.

I wonder if it has to do with one bank of throttle actuator?

[pbonsalb]

I think you would get codes if the TA were not performing equally.

Seems like under more load (higher gear) or with more back pressure (cats installed), the motor pulls more cleanly from 2000 rpm. I tend to doubt that is a spark issue, but I am not an expert who works on these cars every day. Every now and then someone finds a plug or two that are loose or a coil that is bad.

As I approach 100k miles (96k now) on my old car (2008), I have thought about changing the coils as preventative maintenance out of concern that they play a role in the ionic knock sensing system. I am similarly thinking about sending the fuel injectors out for cleaning and flow balancing. But I don’t know that either coils or injectors are your issue.

Have you tried a good scanner for shadow codes? Beware some tunes suppress codes or at least some codes.