505 sti bugger to start when hot and left for about 15 mins

[Warren Gordon]

I hav ean sti and before that it was an sli wagon. this cara lways starts well when cold. after it has warmed up and been driven a reasonable distance thenleft, turned off that is, it starts and runs on less than four cylinders and takes a while to cantch on to the rest that are missing the longer it is left the less cylinders that fire until it reaches the stage where it won't. When the car was an sli I hot wired the cold start injector so it would always go until that turned off after 30 secs, a few goes like that and it would run no problem. With this new ( second hand ) motor the problem seems to be the same, although I have not hot wired the cold start injector this time. The only common items I still have are the fuel pump, pressure regulator and the injectors. I suspect the injectors are at fault, but at around $ 320 to replace them with no exchange I'm seeking another opinion.

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[LynCliff]

Your right, it's the injectors leaking down and then the theres no fuel in the line from the fuel distributor to the injector when you start up. STI injection nozzles work like diesel injectors in that they don,t blow off until a certain pressure is reached, (about 45psi). Pressure is stored in the system when the moter is switched off but faulty injector,s bleed it off and it can take a while to refill those small diamater lines. You could try getting them cleaned at a fuel injection specialist as this sometime works or maybe picking up some second hand ones from a wrecker. It is common problem though with the KJet System.

[Warren Gordon]

Thanks Lyn. I thought that was it but wanted another opinion.
Like your logo, I've got a couple of 604's myself.
Thanks again.