bobsimes
Member
I have a 75hp 1.4 tdi 2002
for the last few months i get an intermitent underboost code ( negative charge pressure) thrown on vag-com which causes the car to go into limp mode until the engine is turned off and back on again.
this limp mode seems to happen on full power on an incline eg joining a motorway maybe once or twice a month.
i suspect a leak in one of the hoses and at worst the intercooler (which was last changed about 4 years ago) which i am going to try and locate this weekend.
however over the last couple of days i have lost cruise control, i have made all the usual checks and ruled out the brake switch and bulbs ect. vag com shows the brake and clutch pedal switches working fine however for some reason i cannot get group 66 to show cruise switches, it says error.
i cleared the fault code re the underboost and cruise worked again until joining the motorway, again i lost cruise but the turbo did not go into limp???
cruise will not return until i log onto vag-com and reset all fault codes of which there is normaly only the one overboost code.
has anyone else had this problem re loss of cruise after going into limp mode or can offer any tips.
i am also thinking it may be n75 valve, what should it normally sound like at idle or is there any way for the home mechanic to check it is working correctly??
for the last few months i get an intermitent underboost code ( negative charge pressure) thrown on vag-com which causes the car to go into limp mode until the engine is turned off and back on again.
this limp mode seems to happen on full power on an incline eg joining a motorway maybe once or twice a month.
i suspect a leak in one of the hoses and at worst the intercooler (which was last changed about 4 years ago) which i am going to try and locate this weekend.
however over the last couple of days i have lost cruise control, i have made all the usual checks and ruled out the brake switch and bulbs ect. vag com shows the brake and clutch pedal switches working fine however for some reason i cannot get group 66 to show cruise switches, it says error.
i cleared the fault code re the underboost and cruise worked again until joining the motorway, again i lost cruise but the turbo did not go into limp???
cruise will not return until i log onto vag-com and reset all fault codes of which there is normaly only the one overboost code.
has anyone else had this problem re loss of cruise after going into limp mode or can offer any tips.
i am also thinking it may be n75 valve, what should it normally sound like at idle or is there any way for the home mechanic to check it is working correctly??
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