WikedV12

Good morning everyone,

I've been enjoying my CL65 and this weekend I was doing some maintenance. As I was listening to the car, I decided to give the car some rev's just to hear it. Now, normally I don't rev up my cars while they sit in neutral. But I do enjoy hearing them rev a little. Well, I decided to rev the CL65 and noticed that it would rev up to 3,000 rpm and stop. I tried a few revs and each time it stops at 3,000 rpms. I then tried flooring the car, just out of curiosity, and it still revs to 3,000 rpms and stays there. I'm assuming this is a safety system to prevent the cars from over revving when parked in neutral, but I've never had that in any of my other cars.

Also, when I was driving the car to show it to a friend I noticed that the car didn't seem as quick as it first did when I bought it. Maybe I'm getting use to it, but it felt slower. My friend was very impressed. I've checked and I don't have any codes and the car runs at normal temperature. Is it possible the intercooler pump is going out but not throwing a code? Is it worth it to upgrade to a better pump, if there is such a thing?

Just thought I would confirm that this is correct with the experts here.

Thanks.

Geraldius

The 3K rev limit while in park or neutral seems about right. Mine does the same thing.

These engines will drop the boost if the intake air temperatures get too high. Could be a problem in your intercooler system. Check for stored IAT over-temp codes. These won't throw a CEL.
I've been having the same problem. I noticed it down on power when hot or after driving for a while in hot weather or city traffic. In my case the intercooler coolant was low. I have to keep refilling it and bleeding the air. One of the things I did to help monitor this was to use an OBDII blue tooth dongle together with an Android tablet app called "Torque". You can monitor IAT and Boost (along with al lot of other things) while driving, using the Torque app with virtual gauges.

WikedV12

Thanks. The car had been driven for a while in traffic and these cars seem to run hot. I don't know how those intercoolers do anything except heat up the air. The water intercooler on my Cobra runs WAY cooler. The air to air intercooler on my Turbo diesel is almost cold. I wonder if an additional intercooler reservoir would help? These intercoolers just don't seem effective at all.

BlownV8

Your pump may be dead.

AMG-Driver

The intercoolers are not bad, when everything is correct in the system and when you are on the throttle (pump is working) and you get some wind from the front.

They work quite well on the highway with a tune and even better if you get a stronger pump.

WikedV12

Thanks for the input. Is it possible for the pump to go dead or be on its way out and not throw a code? Any sure way to tell?

Also, where do I buy a better pump from?

Thanks.

AMG-Driver

You can search for the big Intercooler/Pump thread from "Welwynnick" hope I spelled it right - here on MB World, with flow charts and a lot of helpful information.

I have the Pierburg CWA100 Pump in my SL65, you can buy it aftermarket or a little more expensive from the MB-Dealer. Great little pump.
It is used in the new R231 SL63/SL65 and also new E63 from my knowledge.

My original pump also went dead, I think I had a code high intake temperature stored. But it is not always stored.

I detected it with my Torque App via OBD2 Port / Bluetooth. Once the motor was warm the Intake temperature didn't went down anymore. And plenty of power was gone.

WikedV12

So, the best way to test if I have no codes is to use an OBD code reader and read the live data stream and see what the IAT is compared to the outside temp?

I read some other posts and is this the best pump: Meziere WP136s

AMG-Driver

The Pierburg is stronger against backpressure and also quieter.

RaceHorse

Besides a replacement pump, you should consider a supplemental heat exchange. Circulation is important, but additional surface area to dissipate heat is critical in lowering the liquid temps to recover more heat. If it is hot out and the coolant is circulating but not really dropping in temp, it doesn't have the ability to pull out heat effectivlely from the intercooler. A reservoir of any size will help since the stock setup gets hot coolant expands and bleeds out the back with no overflow. The supplemental heat exchange adds to efficiency.

WikedV12

Is there a place to buy the extra intercooler and reservoir tank? Maybe a premade kit? Space seems so limited in these cars so generic stuff seems like it would not work.
On a side note I drove my S/C Tundra today and did a lot of fast acceleration and when I got out I felt the intercooler and it was cool to the touch. Makes me think I should use the factory Toyota S/C pump and intercooler but not sure where to mount it.

Thanks again for all the help.

ItalianJoe1

Any pump will work, but the key to the V12 system is having it 100% air free and working correctly, it's not bad on a stock engine if it's actually working. Many cars I drive have air in the system or a failed pump and the owners don't even know. Once I got my system sorted, even if it heat soaks sitting parked for 2 hours, within a couple min of driving it cools down fully and is back to crazy power again.

WikedV12

Thanks. So is the Pierburg CWA100 the best replacement pump? Also, it was mentioned to add a coolant reservoir and extra intercooler. Does anyone have a link to those?

Thanks again.