SL55/63/65/R230 AMG: Problems with my RENNTECH SL63
Thread Starter
Junior Member
Joined: Jun 2009
Posts: 59
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C63
Problems with my RENNTECH SL63
2009 SL63 13500 miles RENNTECH
RENNTECH Headers, ECU
Secoundary Cat delete, removed resnators
KN&N drop ins, removed charcol filters
Car was preforming real good in the beging but after the first problem i had with the "AIR SENSORS" which i got them fixed same day, same day after i got the car back from the service i felt the car is leacking air from the factory Air box so took it back again and it is sitcking their for the weekend every car has its problems but my car is leaking power.
I dynod the car three days before all this happend, 389whp 366rwtq in fifth gear, alot of humidaty that day but i think my car should of made much more power by the way i did send the ECU to Rennteck to make sure everything is working properly and also i was about to forget to mention that i had problem with the AC blower ( I guess it have nothing to do with the tune ) . plz help
RENNTECH Headers, ECU
Secoundary Cat delete, removed resnators
KN&N drop ins, removed charcol filters
Car was preforming real good in the beging but after the first problem i had with the "AIR SENSORS" which i got them fixed same day, same day after i got the car back from the service i felt the car is leacking air from the factory Air box so took it back again and it is sitcking their for the weekend every car has its problems but my car is leaking power.
I dynod the car three days before all this happend, 389whp 366rwtq in fifth gear, alot of humidaty that day but i think my car should of made much more power by the way i did send the ECU to Rennteck to make sure everything is working properly and also i was about to forget to mention that i had problem with the AC blower ( I guess it have nothing to do with the tune ) . plz help
MBWorld Fanatic!
Joined: Nov 2006
Posts: 9,137
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From: California, USA
E63 P30, CL500 Sport
390 whp is a hair lower than a stock car (let alone an ECU/Headers car). Normally, these engines dyno around 410 whp (average). On a bad day, I've seen them do anywhere from 394 to 400 whp. While at the dealer, it maybe possible that they have flashed over your RennTech ECU with their latest updates 
I would have RennTech check to see if their tune is still on the car.
I would have RennTech check to see if their tune is still on the car.
Thread Starter
Junior Member
Joined: Jun 2009
Posts: 59
Likes: 0
C63
390 whp is a hair lower than a stock car (let alone an ECU/Headers car). Normally, these engines dyno around 410 whp (average). On a bad day, I've seen them do anywhere from 394 to 400 whp. While at the dealer, it maybe possible that they have flashed over your RennTech ECU with their latest updates I would have RennTech check to see if their tune is still on the car.
I would have RennTech check to see if their tune is still on the car.
Junior Member
Joined: Oct 2009
Posts: 18
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SL55
Take it back to the shop where you had the work done and see if everything has been installed properly. If you still have an issue, take off all the aftermarket work and see if everything is well with your vehicle in stock mode. If there is an issue, then go to your MB dealer and have a full diagnostic done on the vehicle to see what is causing an issue.
MBWorld Fanatic!
Joined: Apr 2008
Posts: 2,838
Likes: 19
From: U.K.
SL 63 W/B AMG , S600,C220
Hi, I have a re-mapped SL63 and K&N filters.
I am worried about the oil in the filters affecting my MAF, is this the problem
with yours, if it is I'LL take them out, shame as I felt a definite increase after fitting them. I'm not sure changing exhaust on a nat *** engine will do much.
Good luck fixing her!
I am worried about the oil in the filters affecting my MAF, is this the problem
with yours, if it is I'LL take them out, shame as I felt a definite increase after fitting them. I'm not sure changing exhaust on a nat *** engine will do much.
Good luck fixing her!
