Now you might think that spraying lighter gas just about a hot engine isnt wise, however the flash /ignition tapering off of gas is about 400C for that reason you obsession a naked blaze or spark to set it off and Ive used this method for many years without incident. function your mannerism through each realizable joint one at a mature and you should locate it. I use a slightly flattened fragment of brake pipe and some rubber hose from the can of lighter gas to find the money for a spraying wand and permit a attend to blast of gas into each area, especially those difficult to achieve later than large implements.
Its in addition to worth getting the fuel pressure checked as if this is low due to a blocked filter or faulty regulator or even a not at your best pump will all repercussion in insufficient fuel brute delivered to the engine. Might in addition to be worth cleaning out the idle swiftness control motor / valve as these acquire clogged up bearing in mind carbon and some brake cleaner washed through helps forgive things off.
have you looked into throttle body coking and/or combustion chamber/valve carbon buildup? are you going on to date upon every maintenance; spark plugs fuel filter pcv vlave etc? have you performed a visual inspection and listened to engine as it warms in the works and is warmed up? oftentimes in engine perform many factors may cause the same symptom(s)