Hi all, had my is200 for about three years now. Never had a single problem untill i took it in for a service this time last year. When i got the car back i drove about 15 miles home on the motorway, when i stopped at traffic lights my revs dropped and just as they came to rest my oil light came on (oil pressure not the one with wiggly lines). As soon as i reved the engine the light went out but would return when the revs dropped. Took it back to the mechanic (who is a well TRUSTED friend of mine) and he said that he suspected a lazy oil pump or pressure switch. I didn't get into apportioning blame as i trust this mechanic 100%. Bit the bullet and opted for pressure test which confirmed it was suffering from low pressure. When the light flicked on the pressure gauge shown a drop. I replaced the pressure switch and oil pump and drove of the next day happy. This was a year ago now and hey presto the oil light has started coming back on. Not seen it for a year and now it's back. My mechanic has asked me what i want to do. He is reluctant to fit a new pump as this should be fine. He has recommended going direct to lexus but i simply don't have the money to go down that road. After a lot of searching over the past couple of days i have loads of questions but no real answers. The car has always been serviced on time. Has done 125,000 miles on a W plate.
Could this be an oil temperature problem? If the oil got to hot would it become to thin??? (only seems to do it when the car has had a long drive i.e engine really hot). Coolants and engine temp seem fine but not really investigated.
Could i set the idle revs slightly higher? revs seem to drop to about 500 - 600 when engine is upto temp. Is this right.
I have browsed the forums and internet to no result.
Any help, ideas, suggestions or magic wands please feel free any input much appreciated!