99 1.8T tip. Just replaced TB 2-3K ago. Car ran perfect. Now has high idle(1200-1500) and slight surge. NO CEL.

Codes: 18021-MIL control circuit open or short to plus p1613-35-10 intermitent. 17953 throttle valve control malfunction p1545-35-10 intermitent. 17957 angle sensor 1 for throttle accuator(g187) signal too large. Usually happens after first start(engine warm). Sometimes happens at stop light.

Found bad vac hose on Fuel press reg - replace. seemed to work for couple of starts.
Throttle body is rebuild with life time warranty. Is this my problem?
Does 99 1.8T have and idle air bypass/controller, or does the TB control?
Looking for more vacuum leaks tonight.
O2 sensors?
MAF?
Forgot to clear codes after scan and vacuum hose change.

Any help greatly appreciated.

 

Propane check for vacuum was good, no leaks. Any advice on sensors greatly appreciated. Anything I can check on VAG while running.

 

Same exact problem here. Vaccum lines good as well. Surge and high idle which causes an abnormal vibration at stopsis evident ona case to case basis. Tried adjusting idle via vagcom, no good. Surging hasme to suspect a faultyN75 valve, not sure whether this would cause idle issues..?? No cel's. Let me no Pilot5.0 if you diagnose anything else.

 

17953 = P1545 problem could be the throttle valve tight/sticking, wiring, throttle control unit,

throttle control unit incorporates TP sensor, CTPswitch (if fitted), ISC actuator/position sensor,

you might need a new control unit?

 

Will continue to watch. Just got a Throttle Body from BBA, has a life time warranty. Gents thanks for the info.

 

Verify in your MVB (possibly, 140-01) that you MIL status doesn't show up. IF vag-com indicates that it's ON and the bulb on the cluster isn't lit, that'll explain your first code.

I've read of ppl getting a bad reman TCU (from BBA reman, too). However, the case of your going out a few months after it running great are probably slim. I'd recheck you connector to the throttle body. Separate the connector and check the pins (female gap). It could just be loose or not seating properly and took a little vibrating over to time to show. Clear the codes and perform a TBA and recheck for code regeneration.