Q: Step by step troubleshooting of DTC fault codes

asked by on July 30, 2016

2005 Hyundai Elantra with the 2.0l engine swapped with a 1.8l engine. Several visits to mechanics have failed to resolve the following issues: 1. The transmission tends to downshift with a jerk. 2. During acceleration, the car usually loses power, hesitating for a while before picking up. 3. When going up an incline with the vehicle slowing as a result, the transmission takes forever to downshift accordingly, thus necessitating me to floor the accelerator to force a response and keep the car in motion. 4. Fuel consumption is extremely high with the vehicle burning a tank of gas over a 200km distance. 5. Engine temperature is between 84 and 87 degrees Celsius when idling and higher when running. Even tho it doesn't overheat, it seems to be pretty high and mostly at mid-gauge. After a long run, a ticking sound emanates from the hood. Speed sensors, fuel pump, converter in the gearbox, ECU, etc., have been changed to no avail. Fault codes are P0077,P0198,P0340,P0501,P0444,P0707,P0560

My car has 138240 miles.
My car has an automatic transmission.

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Each of these codes are for different components and since you swapped the motor with a different size motor than what the car had may be a big problem. You would need to have each code diagnosed separately to see if it can be fixed or not.

You have an engine cam sensor code, transmission shift sensor codes and codes that do not go to your car for the transmission, EVAP code and camshaft solenoid codes.

You may need several hours of diagnostics only to find that the two engine differences are the cause and cannot be fixed.

We have articles on most of the trouble codes you mentioned, for further reading:

P0077

P0198

P0340

P0501

P0707

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