Loss of Power After Spark Plug Change
 

So I changed the spark plugs on my 2003 S600. Everything seemed to go smoothly. Everything came off and out pretty smoothly.

After the change and putting everything back together, no power at all. But no misfires, no shaking, and it seems to rev great in park or neutral. But when I go to drive it, it starts out strong but then a heavy kickback and no power over 2500 rpm. After I park and try to rev, it will hesitate at 2k and then slowly get up to 3k

I used Denso spark plugs, if that matters.

No codes?

I don't know about Denso...I used the NGK that were specified in the OM. Bought them here: https://www.sparkplugs.com/product.aspx?zpid=9795

I also replaced all the red insulators when I did it...they get old and, I suspect, shrink and don't insulate as well after hundreds of hours of heat...

No codes, no shaking, nothing.

It's funny you should mention those insulators, because that was my first thought. A few of them had small chunks out of them and I put them in the coil packs before putting the coil packs on.

I'm wondering if it's maybe a bad contact or grounding on the pack tubes.

The car feels as though the computer is holding it back, like a semi-limp mode. Either that or clogged cats. But they breathed just fine before the change.

Here is the exact same problem after a plug change on a 600

https://mbworld.org/forums/cl-class-...estions-2.html

It is a disconnected hose . Might want to ask the other guy exactly which hose

Double post

Double post

You sir, are a life saver.

The boost pressure sensor right in the middle of everything. Super easy to break plastic tip.


https://cimg2.ibsrv.net/gimg/www.mbw...6964b51e6f.jpg

I removed the broken plastic from the tube and forced the tube over the broken tip and put a small bit silicone adhesive. Drives like new now.