muddy
15-05-2011, 11:11 PM
Initially had erratic tickover when warm, surging between 300 and 1200rpm.
Stage 1.
Discovered original wires to Lamda sensor had burnt/rubbed through on exhaust.
Repaired and clipped out of way.
Still idles lumpily but does not surge.
Stage 2.
Failed MOT on CO and HC.
Suspect temperature sensor may be a cause.
Possible also that previous owner had tinkered with idle speed and CO/mixture screws because he had not discovered damaged Lamda wires.
PS Have cleaned throttle body but not disturbed TP switch.
Update 17th May.
Temp sensor checked out OK for resistance hot and cold.
Replaced Lambda sensor with known good 4-wire spare one from my Passat 1.8T.
BUT .... discovered ECU is outputting 9V on pin that is meant to be earth contact for Lamda sensor .... so ECU is 'fried'.
So am looking for a 2E ECU. Siemens. Part number 037 906 022 GD
eBay is full of ECUs for 2E-engined manual Golf GTi and auto Passats.
ANY good for a manual Passat?
Update 23 May 2011
(as nothing forthcoming on these older Passats from this forum section.)
ECU specialist has stated that it is vital that the last two letters (GD) ARE the same, if using a s/h ECU.
He has known a VW wiring loom catch fire when an ECU with same number but different suffix codes fitted ....
Stage 1.
Discovered original wires to Lamda sensor had burnt/rubbed through on exhaust.
Repaired and clipped out of way.
Still idles lumpily but does not surge.
Stage 2.
Failed MOT on CO and HC.
Suspect temperature sensor may be a cause.
Possible also that previous owner had tinkered with idle speed and CO/mixture screws because he had not discovered damaged Lamda wires.
PS Have cleaned throttle body but not disturbed TP switch.
Update 17th May.
Temp sensor checked out OK for resistance hot and cold.
Replaced Lambda sensor with known good 4-wire spare one from my Passat 1.8T.
BUT .... discovered ECU is outputting 9V on pin that is meant to be earth contact for Lamda sensor .... so ECU is 'fried'.
So am looking for a 2E ECU. Siemens. Part number 037 906 022 GD
eBay is full of ECUs for 2E-engined manual Golf GTi and auto Passats.
ANY good for a manual Passat?
Update 23 May 2011
(as nothing forthcoming on these older Passats from this forum section.)
ECU specialist has stated that it is vital that the last two letters (GD) ARE the same, if using a s/h ECU.
He has known a VW wiring loom catch fire when an ECU with same number but different suffix codes fitted ....