Car has now been in the shop for over a year. In the course of diagnosing the ongoing 82mm throttlebody issues, the CLS doubled down on repairs by crapping out the transmission . I now have a Southern Hotrod transmission and valvebody on order.

Get rid of that 82mm, it's a known gremlin that keeps on going. The hellcat throttle body does not exhibit that same issue and makes better power.

I know I know, I'm likely going to throw in the towel on trying to get it to work. What I don't understand is how going to a larger than 82mm throttlebody will fix the hiccup issue. IIRC even Denroll was having the hiccup with the 90mm throttlebody.

Quick update, during the course of testing TB woes, my transmission crapped out. Ended up replacing with a built OEM+ unit and upgraded valve body from Southern Hotrod. Shifts are quicker but much like Alex from Legit Street Cars experienced the downshifts are pretty harsh but I'm getting used to it. The OEM ECU was also replaced to rule out a bad ECU causing the TB issues. Just got the car back so I'll continue testing/shaking the thing down.

Well the new ECU has not addressed the TB issue which is a bummer. It is marginally harder to reproduce the hiccup probably due to the much much warmer temps. The shifting has improved but there are times when coming to a stop the downshifts are kind of rough. Not too bad in a straight line but it has been a little unsettling when pushing the car a little in a corner. There was a battery drain that was attributed to an alarm unit that stopped working. Symptoms were no more chirps unlocking/locking the car and while the lights would flash when the panic button was pressed, there was no siren.

Been testing out a new tune to address the hiccup, so far things look pretty good. I have not been able to reproduce the issue on the stretch of road that I'm usually able to trigger it. Seems the mpg has improved in highway cruising as well. Unfortunately, the power steering pump blew out today so once again the car is in the shop.

Read through your build thread and was also planning for the 82mm TB, but will keep it in mind for now. I have a lot of stuff to do before adding more power, so we will see in the future My build thread is in my signature

Man, old cars and their old parts:

Power steering pump went out followed a couple months later by the cracked radiator

At this point I've got almost a whole new car

Still working on a slow restoration at this point. Picked up a pair of Hella (OEM) headlamps from Rock Auto to replace my faded headlights that were no longer turning with the steering wheel.... wow what a difference new lights make!

Hella Left Bi-Xeon Headlamp Part Number: 008821351 $638
Hella Right Bi-Xeon Headlamp Part Number: 008821361 $638

Rock Auto prices were easily 50% less than buying from OEM.

While the car was at the shop, I also spent a day with Tony at RaceIQ retuning the car now that I've had his tune for a few months without the 82mm TB hiccup. The air temp was not cooperating with ambient temps in the 80s and pretty muggy. IATs were starting over 100 degrees and hitting close to 140-150 at the end of the pulls so my power was down from the previous 537 that the car made last December. That said it certainly does not feel down on power at all now that temps are in the 50s!

Here is my previous best dyno vs current. Ignore the red AF ratio as it was having some issues during that run:


I also ordered a OEM roof rack so I can mount up a Thule Vector M roof box

Thanks for the partnrs, I have no idea if my adaptive lighting is working to be honest...

You would get a warning on the dash indicating that it isn't working

Good to know

No errors here (knocks on unpainted wood)

Just a few pics of my CLS55 with the OEM roof rack basic carrier part number: 6-7-81-2107 with a Thule Vector M roof box.

That looks way cooler then I expected You can even open the sunroof

Thanks! So far it has been pretty stable at 90+ into a 15 mph headwind .

Not a whole lot new to report. Car has been running great since the tune and completed a 3000 mile road trip out to CA and back with the roofbox and my dog in the back seat. There were some sustained 100mph stretches in NM and AZ and the roofbox held on fine, the car barely noticed it was there

Awesome

Tip; solve the fried egg look with some of these:



Before & after

As a 996 owner I've come to embrace the fried egg look

Hahaha amen

Not everyone is "offended" by it indeed. Which one do you have? Before I bought the CLS, I was also looking at the 996

I've got a 996 Turbo, picked it up while the CLS was in the shop for almost a year. Completely different use case from the CLS: mostly spirited hill country drives and day trips with the wife and dog. The CLS is pretty much the daily driver and highway road trip car but I'm starting to consider selling it for an E63S wagon.

Ah, I was searching for something non-turbo (so NA & supercharged), so I was looking at the normal 3.4/3.6 & the C4S. In hindsight the CLS is the better car, as I need the practicality more often than expected. For instance: the CLS has a way bigger boot space than I expected.

I do like the widebody of the 996 though

Another alternator failed on the car so I had it replaced with a remanufactured one and had the shop add some heat wrap to the header tube closest to the alternator. I also had a new OEM Mercedes alternator on hand and the shop compared the remanufactured one to the OEM and the reman looked beefier as far as the solders and wiring went so fingers crossed it lasts more than 2 years.

I also had the front defrost module replaced on the passenger side as it was no longer blowing hot air and I had to replace the lateral acceleration sensor under the passenger side seat as that had also failed.

The rear end high speed wobble appears to be from a bent rear wheel at the hub so that meant buying new wheels. I bought a set of: https://www.bbs-usa.com/bbs_unlimited/ 19x9et24 front and 19x10.5et27.5 rear from Eric at www.supremepower.com. I'm interested to see how the TUV certified spacer setup works on the BBS wheels since I could theoretically either change the offset later or mount the wheels to another car.

Those BBS wheels look like the Japan Racing SL-01 wheels I have on my CLS. That will probably look good Why did you choose 19" over 20"?

Comfort . I do a lot of road trips and the roads in town aren't all that great so I'll take a little more sidewall for the added comfort.