Im pretty sure i have a bad fuel injector my 94 f 250 4x4 it takes a long time to start up (turns over but takes a long time to start up)everyone tells me its a bad fuel injector.my truck has a 351w engine.how do I go about finding the bad injector whats the easy way to test I have never done anything like this before and cant afford a shop.when I find the bad injector can I buy just one new injector or do I have to buy a set of 8?I hope not.Or is there some way to clean the bad injector?anyway my truck is getting really hard to start up and I want to fix it soon as possible.just to let you know I gave the truck a tune up last week new plugs wires cap rotor and also a new fuel filter i have to gas tanks and its hard to start the truck up on both tanks.thanks ps i used fuel injector cleaner you put in the gas tank about 4 times it did nothing.

 

I would rather replace all of them, especially on an older engine and/or one with higher miles. When I had to replace my injectors, I went with a set of Ford Racing injectors from Summit. Jegs should have them too. If they don't have the Ford Racing injectors in 19 lb then the Accel ones will be fine too. They were about 200 bucks for the set.

You can also get sets of refurbished ones on Ebay for about 100 bucks or so. Just make sure you get 19 lb injectors. Its not too difficult to replace them. You just remove the upper intake and a few other things and the fuel rail. By the way the injectors for the 5.0 are the same as the ones for your 5.8. There are a couple different designs but they are all basically the same thing.

 

Service the injectors yourself: Ford Fuel Injection Fuel Injector Cleaning

I would also suggest to check your spark. Pull a plug, crank the engine over verify what color the spark is. It should be a nice bright blue.

 

I would also suggest to check to see if you have any codes stored in memory along with the hard code check (KOEO).

I do not think putting an fuel injector cleaner in your the gas tank ever did anything for anybody. You need to run the engine on injector cleaner with the fuel pumps and fuel pressure regulator disabled. Keep about 35 PSI on the injector cleaner for a V-8 and run the engine this way for about 15 minutes.
Then do the seafoam cleaning into the intake.
Then change the oil.
This has always worked very well for me.

 

the miles are not high for a 94 it has 124k would you still replace them all?where do i buy fuel injectors anyway?from the dealer?I see some on e bay but they say that there rebuilt are rebuilt injectors any good?

 

sea foam?im not really sure what that is how does this clean the injectors?isnt sea foam for boats?

 

i see they sell it at auto zone ill buy some its worth a try.

 

Put the sea foam in by way of the brake booster hose.

 

Hard starting(long cranking times) is more likely a fuel pressure problem so check that and pull the codes before you spend a dime on any more parts.

 

That's what I was going to say. Pull codes and check your fuel pressure before you buy a bunch of stuff you might not need right now.