Hello everyone, recently started working on my old 1990 Ford F150(5.8 from the Factory) original owner said the engine was replaced with a 5.8 out of a bronco(No idea what year but it has low miles) however every 5.8 I've seen has been stamped with a 5.8 on the upper intake manifold mine says Ford Electronic Fuel Injection so could this actually be a 5.0? The check engine light comes on every now and again but that might be an o2 sensor. If anyone has any info on this would make my day

 

I don't think that would mean it's a 5.0 mines a 5.0 and it's also stamped on the top of the intake like the 5.8. A lot of smart people on this forum someone more knowledgeable will chime in and let you know. Thats as far as my knowledge goes on that matter.