has a friends URS4 come in the shop recently with a no run condition. first i assumed it was either one of the crank sensors or the cam sensor. i started with the cam sensor and to my amazement when i unplugged the cam sensor the connector on the sensor fell apart so i assumed that was my problem. i soldered in a new plug off of a junk cam sensor and the car fired right up. anyhow a day later the car is back again with a no run and my buddy said the tach was jumping around so than i pointed the finger at the G28, the RPM sensor. i took the pair that was almost brand new off of my AAN swapped 4000 and installled them on the car and it fired right up again. this time i just let it sit and idle for around 10 minutes where it than just shut off. i never shut the key off or anything and i hooked my laptop to it and proceeded to scan the ECU with vag com.
the fault i found that i cannot find any information on at all. also the fault was displayed 3 times which i found really strange.
i tried googleing it and there is absolutely nothing about this fault at all. have any of you seen this before and what was the cause of this odd fault?
"The really good drivers got the bugs on the side windows" Walter Röhrl
84 4000S quattro-AAN swapped 83 UR quattro 95 URS6 avant 95 URS6 sedan 90 90 sedan-AAN swapped 91 200 20V turbo 92 GTI VR6 92 GTI G60 X-flow turbo 86 16V jetta coupe
im not a member on quattroworld. anyhow i did end up figuring out the problem. turned out that the fuel/timing chip was loose in the ECU socket. i found the issue by accident, i had the ECU out laying on the floor with the car running and i dropped my screw driver on it by accident and the car shut off. so i started the car again and tapped the ECU with my hand and it shut off again. that told me that the ECU was modded and that one of the chips had to be loose in the stocket right away. the car has an old MTM 1+ chip set and one of the super old bosch 300kpa sensors in it so its been in there for a looong time. i ended up reseating both timing/fuel chip and the boost chip and putting some hot glue on the corners to make sure they stay seated this time and that problem was solved.
"The really good drivers got the bugs on the side windows" Walter Röhrl
84 4000S quattro-AAN swapped 83 UR quattro 95 URS6 avant 95 URS6 sedan 90 90 sedan-AAN swapped 91 200 20V turbo 92 GTI VR6 92 GTI G60 X-flow turbo 86 16V jetta coupe
URS ECU is actually a pretty tough ECU, only real failures i've ever see was when this one guy decided to wash his engine bay and he fried the coil driver chips on the board. Theres no way to get replacement drivers as their a bosch item only and they dont make or sell them. i have seen a few other with loose chips corrupt the chip data before too but that was easy as erase the chips and reburn them to fix it. the loose chips seem to be a trend when low quality DIP sockets are installed.
"The really good drivers got the bugs on the side windows" Walter Röhrl
84 4000S quattro-AAN swapped 83 UR quattro 95 URS6 avant 95 URS6 sedan 90 90 sedan-AAN swapped 91 200 20V turbo 92 GTI VR6 92 GTI G60 X-flow turbo 86 16V jetta coupe
