sputtering at 2000 rpms

[catjim813]

All, I have a 69 280 sl manual that sputters at about 2000 rpms.  It started after recent rebuild, before rebuild car ran great but smoked during start up and heavy acceleration. After rebuild sputters at two thousand rpms or so but drives well at highway speeds.  Starts up well and idles at about 750 to eight hundred after warm up.  injectors are about two years old, injector pump appears to be working well. Ngk non resistor plugs Bosch wires and 123 dizzy.  it has me stumped.  before rebuild compression was 120 across the board now 170 across all cylinders.  Thanks for all the help I have been given before.  just cant get it running well.   Also it does not seem to be burning all the fuel correctly.  No smoke black or blue.  When it sputters If I put the car at full throttle it drives on out well.  What could it be?

[ja17]

Hello,

Possibly the 123 ?  Also make sure that the linkage set-up is correct.

[Cees Klumper]

Maybe worth trying a fresh set of plugs too, just in case

[UJJ]

It maybe "Magerruckeln" fuel mixture too lean!
I had the same problem between 2000 and 3000 rpm. However, it only was present at half or less throttle. At full throttle it did not stutter.
I adjusted the fuel mixture at the FIP and all is good.
Happy Thanksgiving to you all, Urban

[ctaylor738]

Before doing more testing, can you take the distributor cap off and look at the rotor button in the center of the cap?  Make sure it's not broken.  This has been a problem with the Beru caps that come with the 123 distributors.

CT

[catjim813]

Thanks for the replies will check all items mentioned and get back to the group after Turkey Day..

[Naj ✝︎]

It maybe "Magerruckeln" fuel mixture too lean!
I had the same problem between 2000 and 3000 rpm. However, it only was present at half or less throttle. At full throttle it did not stutter.
I adjusted the fuel mixture at the FIP and all is good.
Happy Thanksgiving to you all, Urban

magerruckeln = mid range ?

naj
      

[UJJ]

Naj

"Magerruckeln" (German) = lean stutter or lean fuel mixture
Best, Urban