Hello everyone, I got a small problem on this golf gti, After a big motor repair, now every time i start the engine the 5th injector run, and when the injector run the engine doesn't start quickly, needs more them 8 seconds to run,the temperature are normal, (about 20ºC) BUT if i disconnect/unplug the 5th injector the engine run instantly! i test the temperature senders the 3 under distributor and on head all with the same resistance around 1000ohms on this morning...can any one tell me what make this injector work? Thanks
the 5th injector is controlled by the big brown 2 pin thermoswitch on the side of the head, sounds like its broken or the green/white wire is shorted to earth. more info here: https://clubgti.com/forums/index.ph...air-and-tune-your-mk2-corrado-1-8-16v.195423/
thanks!!!! did you believe on this angle i did't see the thermoswitch? i will go test and after i post on forum, Thanks!!!
with the engine middle hot +/- 70ºC the thermoswitch shows a resistance 69ohms...now i will wait at morning to see the difference of value
simple test, unplug the thermoswitch and remove the 5th injector from the engine and drop in a container. when engine is cold crank it over and see if 5th injector sprays, If it doesnt the wiring is all fine. The green/white pin on the thermoswitch should allow the 5th injector to earth to the head cold, then break the circuit when cold. the red/black wire feeds a heater inside the thermoswitch which stops the 5th injector spraying if the engien is cranking over for a long time without starting So you dont check resistance between the pins as they arent connected, you check between each pin and the side of the head worth checking the wiring to the plug in case its been repaired incorrectly in the past, the green/white is 5th injector earth and red/black is cranking live from the fusebox:
Hello rubjonny, thanks for your help, the thermoswitch are working fine, the green/white on brown plug has direct with green of blue plug, with temperature 15ºc (cold) the pin on thermoswitch have earth (0.3ohms), the other just receive 12v when cracking and cut the earth of another pin because the motor doesn't start, but the problem is the 5th injector when on cracking are continuously injecting fuel, and just when the thermoswitch cut the earth its was when the engine run... if i unplug the 5th injector the motor run instantly... do you know the temperature at the thermoswitch cut the earth? or do you know the reference of this thermoswitch? best regards.
Thermoswitch for the KR is part number 043906163A, and temperature cut is 35 degrees. If the car wont start cold with the 5th injector plugged then perhaps your injectors are leaking after the engine is switched off dripping excess fuel into the intake. Injector tests are covered in my 16v troubleshooting thread