i bought a 1995 vw jetta and it had a engine swop it has a 1998 vw jetta motor in it and the car does not idle right do i need to get the 1998 computer for the motor to run right ???
What is wrong with the idle does it just surge up and down?
Danny
it putters like its going to die
i put new spark plugs in it and new spark plug wires and i cleaned the throttle body but it still idles like its going to die.
Normally this is a pay site but I don't have a definitive answer without being there so I'm not going to hit the answer button.
What I can say is this. A 1995 is an OBD 1 motor and a 1998 is an OBD2 motor which means that the sensors have different connections and in some cases may have different sensors altogether. The sensors are interchangeable so if the person who did the swap correctly put all the original sensors on the engine then you don't need the new engine computer. Mechanically the engines should be the same, ABA 2.0 VW engines.
Not only that, but since they are different generations of electronics, you couldn't put the 98 engine computer into your 95 without changing out the wiring harness, and that would mean also buying all the sensors for the 98 and swapping them back in as well.
I sincerely doubt this is the issue, more likely you have a vacuum leak, dirty fuel injectors, timing is off, bad mass airflow sensor, something like that.
i tried to test it for codes i plug the diagnostic computer in and it says error and i tried using a jumper on it but that just turns the engine light off and does not flash any codes why is this?