i have an elantra 2002 and the check engine light keeps coming on and i will feel a jerk in the engine and it seems to have power loss hwat am i looking at and how much would it cost i am the 2nd owner of the carand have no warranty on it.i have 91000 miles on it any help will be greatful


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Run it by Autozone and have them pull the CEL code for you.
From your description, it sounds like the engine is missing. Changing the plugs/wires usually clears that up.
Get that code first and we'll go from there.

 

i took my car to my local mechanic to retrieve the codes 3 codes came up 1 was for evap leak which he wasnt concerned about.the other code came up as evap purge valve which he still wasnt too concerned about,but the 3rd code came up was po1529 for transmission code ,this one he was concerned about but not familiar with .I told him ill contact web tech to see what your reply is.he did reset my codes and the check engine light didnt come on riding home.would like to know what your opinion is.


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The evap leaks are something to worry about mainly b/c you're releasing gas fumes into the atmosphere.
The Evap (Evaporative Emission Control System) is made to maintain fuel tank pressure. A leak can mean a loss of pressure, and start robbing you of gas mileage, and cause abnormal engine operation due to lower fuel pressure.
The code thrown for the purge valve is one to look into. Replacing the valve, in most cases, takes an hour or so. (The Purge (P) point is a common source of evap leaks)
Have your evap system checked for leaks by using a fogger machine. It runs a harmless smoke through the evap & fuel system, and the smoke comes out through any leaking places.
It sounds as though, b/c you have a purge valve code, thats the source of both codes.
RUn a smoke test first, and if it leaks out of the purge valve, replace it then retest. Either way though, the P/V is not functioning, so it should be replaced.
If an open evap leak is present, or the purge valve is malfunctiong, the vapors could build up and excessive pressure and cause an explosion in the fuel tank.

Heres a picture of a standard evap system and the fuel vapors travelings for you:

 

josh thank for the pics and info but what about that transmission code or is this code caused by the purge valve


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Are you sure you got that one code right? "po1529" is not a valid code. The codes all have a letter, followed by four numbers. So it could be P0152 or P0129 or whatever, but PO1529 can't be a real code cuz there's too many digits.

 

The code thrown for the tranny is in no way related to the evap system faults.
The code is nota P01529, its a P1529.
Its a code that usually comes along with a P0715, a speed sensor failure.

P0715 - Input/Turbine Speed Sensor Circuit Malfunction
P1529 - SCAIR Solenoid Circuit Malfunction

After doing a small bit of research, I found out that sensor has a history of failure.
Have it checked. Its nothing overly serious, but still nobody likes a CEL on.
Worry about the evap problems first.