Here is the deal,
96 4x4 with 150,000 miles on it. I bought it off ebay CHEAP

I have had issues with codes, leaks, miss fires.......

This weekend I tried to get every thing cleared up, but I am missing something. I had P0300, P0175 codes, minor leak code... After chasing all weekend, I have replaced spark plugs, wires, cap, rotor,O2 sensors (all of them) fuel filter, fuel tank and pump ( had a rusted tank), and lots of vacume line.

Now that all that is done, I have a rough idle still. P0306 code today. I checked the plug and it is black ( running rich I think).

I don't know where to go from here. I am guessing that the injector to that plug may be leaking or clogged? It looks like it is a pain in the a$$ to get to. Is there any way to clean them or do I have to replace it? For that matter, can I replace just one or do I have to do all of them?

Any help or hints on what do next would be great!!

 

How did the rest of the plugs look? If they looked good/normal, then there is a problem with that cylinder. The problem could be related to the fuel system or a compression problem.

Have you checked the compression on that cylinder and compared it with the rest of the engine?

 

I gave up for today, I will get back on in the morning.

No, I did not look at the other plugs because I am now getting only the 306 code. I will check out the rest of them in the morning. I do not have a compression tester. I will need to get one from autozone or some where.

 

I cleared all my codes and decided to start over. I get p0306 only. I put my pressure gauge on fuel line, turned on the key and got about 50-55 psi. Turned off the key and the pressure dropped off to about 40psi in 5 minutes or so.

Cold start is great, when it warms up it takes awhile to get started.

Can I replace only one injector?

 

I would see what's causing that leak down...

You can replace only one injector, however, you may end up with the same problem. All of the injectors have experienced nearly identical operating conditions. Replacing one injector can cause an imbalance on that side.

Before jumping at replacing injectors, you'll want to do a compression test. While you have all of the plugs out, compare them.