I need help

I bought 91 on ebay, I was a fool to buy so now I have spent the last yr trying to rectify mistake. These are the thing I have done to motor. Let me start out by saying that original problem still exist and is the reason I am starting this thread.

I rebuilt motor, new MAF, wires, cap , O2 sensor
Motor runs very rich, hard to start but will idle, black smoke real bad after idle, 3 and 4 cylinders not hitting. gas smell really bad, still has pretty good power. I need to sell or fix before I go crazy. Motor was rebuilt right.

We need more infromation: Make, model, engine size, and what the original complaint was that made you rebuild.

Rod was knocking, That was reason for rebuild, Truck was running rich before I tore it down. I wanted to fix majors and then focus on minors. Truth be known I should have junked truck, but when you do something stupid you try to make it right. I bought truck against my better judgement however I gave my word. My reputation is more inportant. If I say I will buy something then I do it and let the chips fall where they may.

With all of that being said . This truck will run but it drinks the gas like a big mama and really does not run real well. I do think I have the timing right if that helps. She starts hard and really smell of raw fuel. I am no mechanic. I bought a dvd on how to rebuild motor and just tackled it. I do have chiltons but I am to dumb to comprehend much that is in it.

It is a 91 nissan 4X4 pick up with a ka24e stock with a new crank and head. If any one needs parts this may turn out to be a donor

I dont mind telling you that the expense is getting to be a big factor. and so is the hurt pride.

Is it fuel injected or carburated? Fuel pressure regulators, floats and leaky/stuck injectors eat gas and can flood the engine making it hard to start.

Is the timing belt/chain indexed properly? Timing belt/chain out just a little makes them hard to start and hungry!!!

Are all sensors hooked up? Bad coolant temperature sensors and air temperature sensors can cause computers to think the engine is too cold all the time and richen the mixture (gulp gulp). Computer uses these since you don't have a choke with fuel injection.

It is fuel injected, How do you check for stuck injectors and how do you check temp sensor. It has a timing chain, I really think I have timi ng chain on right. I checked wiring harness at that sensor and cannot get a tester to light up at that sensor. I changed pressure regulator valve last week. I forgot to mention that

how do you index a chain. This truck was running this way when it was bought so I assume no one had messed up internal parts. I really think it has to so with sensors, injectors, ecu box, or wiring harness. any suggestions on how to check any of these will be helpful. I have a tester and a ohm meter but I relly don't know how to use it so any help with that will be appreciated as well.

I cranked truck this morning. Hokked up hot wire to water temp wires, no change. I pulled 3 and 4 spark plug wires and noticed less power but still not as much change in motor sound as you would expect. I do not think 3 and 4 are getting as much spark as needed to burn out fuel. any suggestions on shecking that.

To check for leaky injectors: Let engins sit for overnight. Pull the spark plugs. If any are wet then fuel is leaking through the injectors.

If plugs are not wet, then we are back to sensors. I would just replace the temp sensor and put that one to rest. Not that expensive.

Sounds like you may have some bad plug wires or weak coils also.

injectors are not leaking. How can I check coil? I ppulled temp sensor wire and checked wiring with a test light I can not get it to light up. Should it light up. If it should could this be my ecu box. Would that also cause less fire in 3 and 4 cylinders.

Smokes worse as engine heats up. I ran wire from 1 side of connection to other side on temp sensor wires this morning with no change in how rich fuel seemed to be. but I still ge no current on those wires when truck is running.