could be the pickup in the sump it has a fine gauze that sometimes (through lack of servicing )gets blocked a freind of mine had his blocked and emptoed half his oil and topped up with deisel fuel and run it for 20 mins to unblock it and its still runnin now 3 yrs later (toyota supra ) I said drop sump and take off and clean it and he did the other and I said it wont last but hes got last laugh on me lol
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