Hello all! I have a 2001 Ford Mondeo (2.0 Duratec HE engine) with 47k miles (yes, that’s low for a 19 yo car!) which I’m trying to fix for the past 4 months. Unfortunately, I’m running out of hairs in my head
These are the symptoms:
-At the traffic light, the engine stalls (rough idle) and hesitates when the throttle pedal is pressed, it continues hesitating until ~1500 RPM
-The engine stalls even more if the A/C is turned ON and/or when engine is cold
-High fuel consumption at city
-It gets to the operating temperature too quick
-Fuel trim when stopped is STFT -4% and LTFT +11%
-Fuel trims stabilizes at 0% above 55-60 mph
-When the throttle is briefly pressed and released, the engine takes a couple of seconds to completely reduce the RPMs to idle
-When coasting, if I shift from Drive to Neutral, the RPMs raises to almost 2k and returns to idle only when the car is near to a stop
-The normal RPM for this engine is 720 +/-50, when stopped in Drive, the RPMs stays at ~800 RPM
-Harsh downshift from 3rd to 2nd, unless I brake veeery smoothly
-No error codes
What I did so far:
-Spark plugs changed: little to no difference
-Spark cables: resistance seems OK, all cables below 2k ohms
-Throttle body removed, cleaned and inspected for leaks at the seals and flaps
-Vacuum leak fixed at the injectors (seal changed)
-Injectors tested for leaks
-Vacuum leak fixed at the intake port (intake manifold removed and seals changed)
-PCV hose changed, although it wasn’t broken
-PCV valve inspected, looks fine
-MAF sensor inspected, not dirt or visually damaged
-Thermostat changed, it was physically broken and locked open
-EVAP hoses are not leaking air
-Brake vacuum lines are not leaking air
-Swirl flaps actuator is not leaking air
-Air filter is OK
Where I’m lost:
-I still suspect that there is a vacuum leak somewhere because of the fuel trims and fuel comsumption, but I tried to blow a cigar in the intake manifold and it didn’t leaked anywhere, I put all my lungs on it and nothing. Is there any other way to test for vacuum leaks with efficiency?
-Can it be a fuel pump? It is pretty old despite the low mileage, but at the same time, the car is not hesitating at high RPMs when the pump has to do more effort I suppose.
-I don’t know how to test the coil pack, it can be bad?
Any help/tip is much appreciated!