mk4 golf 1.6 2001 AZD engine.
I gave up trying to figure out why my cars running lean and took it to the garage. Reputable local place. The mechanic couldn't find a air leak. Checked other stuff too. And I told him I changed the temp sensor and he reckons the ecu is trying to re-learn the fuel trim settings for the new sensor as the coolant temp sensor reponse to ecu does something with the fuel ... something about the engine temperature and fuel settings.
He reckons clearing the fault on a diagnostic machine is not the same as obd II or something where he would connect up directly to the ecu to reset the trim settings, so it could re-learn them from the new coolant temp sensor base settings.
He said both lambda are working fine. and could find nothing else wrong.
He did say that as I cleared the fault on my handheld if I just drive it around and see how it goes, check the colour of the plugs in a while and take it from there, and check the scanner for fault codes coming back up.
He also advised me that it could be a MAF problem BUT he then said my car doesn't have a MAF but a MAP (whats that?) I didn;t get a chance to ask. He said that might very need replacing.
Anyone have any thought on this ?
Thanks