Power loss above 4800 RPMs
08-28-2016, 08:57 PM
#1
Super Member
Thread Starter
Power loss above 4800 RPMs
Hey everyone!
I am experiencing a noticable loss in power above 4800 RPMs on my CL600. It pulls like always below that RPM, although throttle response seems a tad sluggish but still bakes the tires at 40 MPH etc. But after the tach swings past 4800 RPMs I can feel a large drop in power. It is far less pronounced at part throttle if that helps in any way? If I go straight to WoT it is down on power through much of the range. I changed the I/C pump to the new Bosch unit with the same results.I cleared all codes (nothing major) and same result: Anything above 4800 RPMs and it noticeably loses power. It has great(normal) power up to that point. Almost feels like a boost leak on an old Eclipse lol. Anything else you guys can think of? I was thinking possibly a MAP sensor? The one by the ignition module with it's source at the left I/C perhaps? I changed this out last year, but it's the only thing I can think of unless the 'Y' pipe between the I/Cs and Throttle Body could have a crack somewhere. Don't these cars make max boost at like 2800 RPMs though? I wouldn't think boost levels would be higher at 4800 would you? I guess I'm going to have to hook up a boost gauge and see if I'm losing boost above that point, if not, I guess is elcerical, like the ECU pulling timing etc. If anyone has any info on this or has experienced the same problem please let me know. Would love to get it fixed so the old girl pulls like she should!
Regards,
Marc
I am experiencing a noticable loss in power above 4800 RPMs on my CL600. It pulls like always below that RPM, although throttle response seems a tad sluggish but still bakes the tires at 40 MPH etc. But after the tach swings past 4800 RPMs I can feel a large drop in power. It is far less pronounced at part throttle if that helps in any way? If I go straight to WoT it is down on power through much of the range. I changed the I/C pump to the new Bosch unit with the same results.I cleared all codes (nothing major) and same result: Anything above 4800 RPMs and it noticeably loses power. It has great(normal) power up to that point. Almost feels like a boost leak on an old Eclipse lol. Anything else you guys can think of? I was thinking possibly a MAP sensor? The one by the ignition module with it's source at the left I/C perhaps? I changed this out last year, but it's the only thing I can think of unless the 'Y' pipe between the I/Cs and Throttle Body could have a crack somewhere. Don't these cars make max boost at like 2800 RPMs though? I wouldn't think boost levels would be higher at 4800 would you? I guess I'm going to have to hook up a boost gauge and see if I'm losing boost above that point, if not, I guess is elcerical, like the ECU pulling timing etc. If anyone has any info on this or has experienced the same problem please let me know. Would love to get it fixed so the old girl pulls like she should!
Regards,
Marc
08-28-2016, 10:49 PM
#2
Former Vendor of MBWorld
do you have a scanner or anything to check you iats? I would start there. if they are high then alteast we know its pulling timing and you have a cooling issue to chase down.
If they are good i would do a boost leak test next.
If they are good i would do a boost leak test next.
08-28-2016, 11:42 PM
#3
Super Member
Thread Starter
Yeah I need to find a decent data logging solution. I'm thinking it's a leak or pulling timing. Thanks for the direction, appreciated. I was hoping maybe someone would chime in with, 'oh yeah, that happened to me too and it's this'. LOL hopeful thinking ya know?
Regards
Regards
