SL/R129: 1991 300 SL slow off the line
Thread Starter
Junior Member
Joined: Nov 2012
Posts: 22
Likes: 0
1991 Mercedes Benz 300 SL
1991 300 SL slow off the line
Hello,
My 1991 300 SL is pretty slow off the line. Although it isn't a consistent thing it happens more often than not. I have had the fuel filters replaced, the fuel pumps replaced, the fuel injectors and all the little rubber hoses that go with the injectors replaced as well. I haven't yet replaced the fuel distributor. The car is stil slow off the line. It is sluggish and my fuel economy, as a result is bad. Before I spend another several hundred dollars trying to rectify this problem can anyone suggest a remedy for this issue? I have looked on previous posts to see if there is anything related to my question and didn't find the information I need.
Thank you,
Phil
My 1991 300 SL is pretty slow off the line. Although it isn't a consistent thing it happens more often than not. I have had the fuel filters replaced, the fuel pumps replaced, the fuel injectors and all the little rubber hoses that go with the injectors replaced as well. I haven't yet replaced the fuel distributor. The car is stil slow off the line. It is sluggish and my fuel economy, as a result is bad. Before I spend another several hundred dollars trying to rectify this problem can anyone suggest a remedy for this issue? I have looked on previous posts to see if there is anything related to my question and didn't find the information I need.
Thank you,
Phil
Banned
Joined: Jan 2006
Posts: 1,982
Likes: 393
From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
I would familiarize myself with the diagnostic manual for this engine. I would check diagnostic codes on socket 3 for the fuel injection and proceed from there.
Newbie
Joined: Jun 2007
Posts: 14
Likes: 1
From: Indy Area
90 300SL, 04 VW Phaeton, 87 Porsche 928, 83 Coupe Deville, 92 GMC, 74 Alfa SPider,
I wouldn't only focus on fuel. It could be ignition related. My 90 300 can be real doggy some days and real zippy others.
I have found that if I "row" the gears myself, it's much more responsive. I believe these normally start and second gear and only downshift to 1st under heavy acceleration and /or activation of the kick down switch.
It's kind of fun, start in low to lock in first gears... run up past 3K RPMs, push forward momentarily and pull back to lock in 2nd. Keep accelerating till you feel the need to 3rd, slide forward a notch. Keep accelerating, move forward one notch for forth, then finally "click" to the right for 5th for steady state speed.
I have found that if I "row" the gears myself, it's much more responsive. I believe these normally start and second gear and only downshift to 1st under heavy acceleration and /or activation of the kick down switch.
It's kind of fun, start in low to lock in first gears... run up past 3K RPMs, push forward momentarily and pull back to lock in 2nd. Keep accelerating till you feel the need to 3rd, slide forward a notch. Keep accelerating, move forward one notch for forth, then finally "click" to the right for 5th for steady state speed.
Banned
Joined: Jan 2006
Posts: 1,982
Likes: 393
From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
It's kind of fun, start in low to lock in first gears... run up past 3K RPMs, push forward momentarily and pull back to lock in 2nd. Keep accelerating till you feel the need to 3rd, slide forward a notch. Keep accelerating, move forward one notch for forth, then finally "click" to the right for 5th for steady state speed.
Super Member
Joined: Jul 2010
Posts: 598
Likes: 19
From: Eastern Kansas
94 SL 600, 98 993, 89 XJS Conv., 85 Daimlier Princess 16 Hybrid Lincoln 16 Chevy crewcab
I hope you replaced parts that weren't meeting specs!
You do have a heavy car with a wonderful but not powerful engine. I never considered the 300 in the 90's a power producer, but in the 300B from the 50's that was and still is a head turner, not a torque monster!
You do have a heavy car with a wonderful but not powerful engine. I never considered the 300 in the 90's a power producer, but in the 300B from the 50's that was and still is a head turner, not a torque monster!
