My 355 has been having a few issues recently, initially it was bad running all the time. The isssue was that it was running rough all of the time which has now been cured with a new MAF sensor. Well that has cured the running when its warm. However it still runs rough whilst warming up ? Someone suggested a warm up regulator but I cant seem to find any information about it ? Does anyone have any ideas ? Thanks
Do you mean the Idle air Control valve (IAC). I have 3 new spares. Or is the warm up regulator a 355 thing I have a 348 so I am not super clear there.
There is not really a physical « warm up regulator » per se, but there is a regulator in the ÉCU control (software) which is using coolant temp as an input, that adjusts fuel mixture while the engine gets up to temperature. I would check the coolant temperature sensors if it is rough when cold only.
Well what do you know, the parts s diagram says there is actually a unit called "Warn-Up Regulator" for the 355. Pretty sure there is a CEL related to coolant temperature sensors, there is for a 348, do you have a Check Engine Light at all? Image Unavailable, Please Login
Yep it is your right! I ran search for 355 to see and it came up but did not notice that. Just a thought, check simple stuff like fouled plugs, I think 355s are a bit rich when starting up.
As Ferrarium has mentioned these cars run rich. If I am not mistaken the '95 models are even more susceptible to fouling plugs than the later years due to the Motronic 2.7. If your car has been idling a lot and not really going anywhere its very possible its just fouled plugs. Even my friends 360CS started doing it once. My car spent some time idling for a while and it started to run a little "off." It wasn't a huge thing, it was subtle, but it was there. I just had to run it through the gears and it was good to go. I bring this up just in case. If its running really rough then I wouldn't drive it without researching more.
