I drive an 87 300e manual, no cat, no lambda.

In my search throguh this forum, I've found there was a change in fuel pump relay in 1987, part number 002 545 27 05 up to engine number A396764 and 003 545 24 05 for engines after that.

I've just checked my new relay and discovered the part number is 003 545 24 05 but the engine number is A351018, which means I should be using the 002 relay.

Now, the engine runs fine apart from the fact that it starts cutting out at 4,000rpm when driving, but not when in neutral or with the clutch in.

The fuel pump relay was replaced as part of a whole series of new bits solving a rough idle/hot start combo, which is now cured. I've also changed the fuel filter, OVP, all injectors and all usual suspects, incluing rotor and cap.

Does anyone know what was changed with the new relay? In particular if there was an introduction or change to the rev limiter element.

I need to know if there's any connection to my problems and whether I can fix or disable the rev limiter before I have to track down the old part and pay for that just to test it out.

Anyone running an old 300e with the new part without problems?