Blinking check engine light 2003 1.8t vw jetta rough idle remedy

The coolant temperature sensor signal to the computer determines fuel injection ratio. When it fails the car will be slow to start and a strong odor of gasoline. turn it off and it will start as normal. A failed sensor will also cause stall at idle speed and poor gas milage. the sensor is located near the top radiator hose connection at the thermostat housing.Use a 19 MM deep well socket.

With so little information reaching a solution is not likely.Does the fault happen every time the engine starts or only the first time? Does the engine run normal after the stumble? If it stumbles after every start a vacuum leak could be the cause. if it stumbles when first started turn it off and restart.If it starts as normal on restart. There is only one reason The coolant temperature sensor has failed. when this happens there will be a strong odor of gasoline. The computer meters fuel based on the signal it gets from the temperature sensor. when there is no signal it meters maximum fuel causing a slow rough first start and poor fuel milage.

One off the leads might be split or air filter blocked or a fuel sensor is not working there are two a left and a right fuel sensor.

When you smell the strong odor of gasoline and the car runs rough the coolant temperature sensor has failed (no exceptions) The engine is usually slow to start the first time. turn it off and it starts right up next try.

Check the fuel filter and the fuel pressure, if it is correct check the calibration of the system bosch jtronic

Air flow sensor.... air temp sonsors... cant tell you more then that with out a trouble code...

The use of contaminated gasoline or gasoline with a low content of deposit control additives may result in one or more of the following conditions:
^ Excessive accumulation of deposits on intake valves, intake manifold, fuel injectors and combustion chambers. ^ Engine runs rough after cold start. ^ Excessive engine cranking time. ^ Hesitations while driving. ^ Rough engine idle. ^ Reduced engine performance. ^ Poor fuel economy. Conditions may be severe enough to illuminate the MIL in conjunction with storage in the ECM data memory of DTCs for misfire (example: P0300, P030x) and / or lean fuel system (example: P0171, P0174, P1128, P1130, P1136, P1138).
Technical Background
^ Condition may be caused by use of contaminated gasoline. ^ Condition may be caused by use of gasoline with a low content of deposit control additives. Production Solution
Not applicable.
Service
If use of contaminated gasoline is suspected:
Consider advising the customer to change gasoline source (brand/gas station). Contaminated gasoline may exhibit one or more of the following characteristics:
^ May have unique color and odor. ^ May contain undissolved water. ^ May contain sediments and suspended matter. ^ May appear cloudy and (after settling) may show signs of separation. Repair:
Gasoline additive G 001 700 03 or G 001770 A2 can be used for removal of existing carbon deposits from:
^ MPI engine ^ Injectors. ^ Combustion chambers. ^ Intake valves. ^ FSI engine ^ Injectors. ^ Combustion chambers. Tip: For removal of carbon deposits from intake valves of FSI engines, refer to TSB 2019948.
Mix the additive with gasoline directly in the full fuel tank following the mix ratio. For example, 60 ml per 30 liters gasoline, 150 ml per 20 gallons of gasoline.

Here's some suggestions. 1.Get some fuel injector cleaner 2.get new air filter 3.get a tune-up 4. check tires for proper air
hopefully that helps

if it continuously runs slow after stepping on the gas w/ poor milage it MAY be something clogged in your exhaust. However I'm having similar probs but a simple "turn engine off and restart" doesn't fix it as mine is misfiring...

first i would change the fuel filter. this is the number one reason for poor gas milage. the engine tries to compansate for the lack of fuel and in the long run this weakens your fuel pump and it will fail sooner rather than later. i als would check the air filter. if the engine can't breath properly it will lose power. if you have not had a tune up I would suggest getting one. this most certainly help boost the performance of your vehicle. i would try and use an additive in your fuel to clean the injectors clogged injectors will make the engine run rough and cause hard starting and rough idle.. the last thing i would have you check is the throttle positon sensor and the O2 sensor. take it to a shop and have them hook a diagnostic scan tool to it this will show if either of these sensors are bad or if they threw a code and the computer is trying to overcompensate for the lack of fuel. hope these options help you. please rate this solution thanks