Suddenly higher RPM at idle
Hello everyone. A day ago, while I was driving I felt like something happened with the engine, I did not depress the throttle pedal more than I needed at that moment, but car slightly accelerated. I put the engine on idle and tacho shows 1000/1100 rpm instead of usual 850/900. Engine temp gauge shows normal temp. Today same thing. Cold engine ok, after warmed up at normal temp, it started acting, goes to 1000/1100rpms then by itself goes to normal. After a few seconds it is ascending again and so on. Then I turn engine off and start again, rpms go up to 1500 then to 1000/1100 and after 4-5 sec. go to normal, then again to 1000/1100... Tried to change relays 109 and 103 - no result. Strange - before engine starts, glow plug light stays on for some 10-15 secs then goes off and no matter it is off or on, engine starts without problem. If engine is cold (e.g.morning), gp light goes off as it should and all is well till eng warmes up to normal... No repair to the engine last 12 months (15k mi) except oil change, fuel/air filter replacements (last year), cabin filter (today) and usual oil refilling after some 1000-2000mi (100-300g.). Never had experience like this, I do not know what to think, getting more and more nervous. Help!
P.S. Car pulls well, no any other problems.
Hello everyone. A day ago, while I was driving I felt like something happened with the engine, I did not depress the throttle pedal more than I needed at that moment, but car slightly accelerated. I put the engine on idle and tacho shows 1000/1100 rpm instead of usual 850/900. Engine temp gauge shows normal temp. Today same thing. Cold engine ok, after warmed up at normal temp, it started acting, goes to 1000/1100rpms then by itself goes to normal. After a few seconds it is ascending again and so on. Then I turn engine off and start again, rpms go up to 1500 then to 1000/1100 and after 4-5 sec. go to normal, then again to 1000/1100... Tried to change relays 109 and 103 - no result. Strange - before engine starts, glow plug light stays on for some 10-15 secs then goes off and no matter it is off or on, engine starts without problem. If engine is cold (e.g.morning), gp light goes off as it should and all is well till eng warmes up to normal... No repair to the engine last 12 months (15k mi) except oil change, fuel/air filter replacements (last year), cabin filter (today) and usual oil refilling after some 1000-2000mi (100-300g.). Never had experience like this, I do not know what to think, getting more and more nervous. Help!
P.S. Car pulls well, no any other problems.
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