i have just bought a my98 sti which i have starting problems when the car is cold it starts no problem but when it gets to its normal running temp it wont start enging turns over but wont fire up ,after about 3hours and engine has cooled it starts fine again it runs with no problems it is standard exept an hks airfilter,if i start car and run it for 5 to 10mis or so ill start ok its only when it reaches its normal running temp it want start ,it is very annoying no warning light come on to show any falts any ideas thanks

 

classic crank sensor failing

 

or cam sensor!

 

good call

 

had exactly the same problems on the STi6 block I put into my MY95.

Was the crank sensor - five minute fix.