strange engine problem
 

hello , can anyone help out ?

3.2 86 engine does strange things :

when cold and idling , the engine is going up and down from 0 RPM to 2000 RPM and eventualy stops running.
when I take the oil filling cap of , the engine is running perfect !
:confused: :confused: :confused: :confused: :confused:

when hot, engine is idling on +/- 1000 RPM and no possibility to lower down , or same strange thing occurs .

somebody had the same problem ?
what to do ?

any advise is welcome !

thanks

When you remove the oil filler cap the mixture will lean out. Sounds your injection setup might be off. Try a search on this issue in this forum.

thanks buster73

i've done that, but can not realy find the cause , or the way to fix it.

seems that removing the cap leans out the mixure, but what to
replace ?

car has just got his big maintenance job , and before it did not suffer of this. before the engine was getting a lot of air through false places.

or is putting a K&N airfilter on the cap a "allowed" solution ?

Disconnect your O2 sensor, and see if that makes any difference.
It should richen up the mixture and settle things down. You may have a bad O2 sensor that sends false signals to the DME, which in turn will adjust the mixture to compensate.

Take it back to where you had the maintenance job done and have them check the mixture. probably they sealed off some air leaks without re-adjusting the mixture. Hopefuly it is just an adjustment and no hardware issue.

yep , will do that (taking back to shop)

I hope they will find the problem soon , did not hear a solution so far from them

thanks for the reply's !

bye bye