[W126 Coupe] Hits Rev Limiter on 1 > 2 Wide Open Throttle

[malcolm369 at comcast.net]

Hello all, 


Mine is an '87 US model with now 121K on the clock that runs smoothly, makes great power plus being in overall very good shape.. I love this car.. 


My question has to do with I guess the Fuel Pump Relay function.. 


When I have had opportunity to really accelerate HARD from a stop , definitely starting in 1st gear.. the car picks up smartly, gets to damn near 6000 rpms and comes up on the rev limiter instead of the expected 1 > 2 upstift. This ONLY happens at wide open throttle and ONLY the 1 > 2 upshift. All other full throttle upshifts occur naturally at roughly 6 grand on the tachometer. 


As I do not usually drive this way it nearly always comes as a surprise to me and is, as you might imagine, VERY ubrupt and seemingly violent as the engine shuts off power at full chat.... (As soon as I release the throttle the car will upshift by the way). 


This occurance has been with the car for roughly six - eight plus years that I've had the car and seen several transmission flushes, filters.. throttle linkage adustments (for full throttle operation)... nothing really to address this particular infrequent (to me) issue. It is fair to say that if pressed on a 1 > 2 full throttle upshift.. it won't.. and resorts to the rev limiter instead. 


The FP relay function, as I understand it, governs the rev limiter and possibly the upshift function at Wide Open Throttle? Or am I looking at some more mechanical / hydraulic gremlin associated with the transmission itself? Kickdown cable adjustment? 


I'd appreciate your wisdom on this one as it has me perplexed.. 


Thanks.. Malcolm 
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