504 Coupe loses power when warm

I've got a 21 year old peugeot 504 coupe which drives like a dream.
But not when the engine is warmed up. .

When the engine is warmed up to normal or just above normal temperature (
not overheated !) and the outside temperature is over 20 degrees Celcius,
the engine loses power.
When I drive away, no problems, but when the rpm's come above 3000, the
engine stutters, as if one or more sparkplugs are disconnected.

I allready renewed the spark plug cables, Sparkplugs are new ( 3 months old)
and the
distributor is clean

I wonder if anyone has an idea what to do

Tia

Mark

 

Does it have an automatic choke?

 

Hi Chris,

I'm affraid there were fuel injections on 504 Coupés (lower specs
4-cylinders shared the sedan TI mechanical fuel injection, IIRC, and V6 also
had fuel injection & an electronic ignition).
In the case there was a Bosch K-Jetronic series injection fit, I'd go for an
incorrect cold start injector management. The solution used by many users of
such injections is to disconnect it (it is electrically powered), and run
without cold start injector. Just give throttle at cold idle.

 

Thanks for the tip, however, Its a Kugelfisher injector and after some
more testing, the symptoms are that its an electrical problem.
When i disconned one of the sparkplugs, the engine runs just as bad as
when its realy warm

'Thanks anyway, and if you're right afterall, i'll let you know

 

Well, this is probably gonna sound rather obvious, but try replacing your HT
leads.

Chris.

 

Yep !

didn't change a thing
also changed the capacitor, no change

 

Plug? Tight tappet? Burnt valve?

 

I brought he car to a local old-timer and peugeot specialist
ignition, cables and plugs were OK !
However, the fuel filters were fuller than full !
Looks like the garage I used to bring the car overlooked it.

Now it seems to be running like a dream

Thanks for all the tips !

Mark