I have a wierd problem with my 88 f250 351. It starts up really good when cold but when its warm it turns over for about 5 seconds before firing up. Any ideas.

 

Sounds like my 302 sometimes. 1989 F150. Cold, it fires right up. When warm, it will sometimes take some cranking to catch and run. Really noticable with remote start, as it won't run first try and have to recrank it again.

Strangely enough, when I've cleaned the IAC, it will be better sometimes. Pretty well tuned up and in good running order otherwise.

 

My 89 f150 351w does that too. I think my injectors might be sticking or something. I have already replace my water temp temp, and air intake temp sensor.