My truck will not start

I have a 2002 GMC Yukon Denali XL and it will not start. When you turn the key it will turn over but will not crank up. I had a new fuel pump installed, new battery, and a new computer. Will you please give me any advice that you have?

Before you spend any more money on parts, find out WHY it won’t start. It needs two things to do so, spark and fuel. Which one are you lacking?

I think you need a real, live, person ----right there —to help you diagnose this problem. Believe it, or not, this is novice mechanic kind of stuff.

Before any of us could even make an educated guess we need to know if the problem is lack of spark or lack of fuel.

Who is doing the diagnosing on this vehicle? From the sound of it they seem to be using a shotgun approach.

About all I can suggest at this point is that you disconnect a small intake manifold vacuum line, shoot a healthy shot of aerosol carb cleaner into the intake, and attempt to start it.

If it starts for a few seconds then you at least know it’s fuel related. No start and no coughing means it’s a spark problem.
It should not be hard to figure out.

I have a full tank of gas and in july I had just my spark plugs replaced

I just bought this truck in April from a dealership called royal motors as a refurbished vehicle. Since then I have had several problems with it. I take it back to the dealer when it breaks but I don’t know if he knows what he is doing. I really don’t know what to do now because I have to go back to work in a few weeks without a reliable vehicle. I spent $12,000 on this truck which took all of my money besides a few hundred. I did that because I thought I was getting a great vehicle since he had to repair the vehicle so it ran like new. I know that before the vehicle wouldn’t start I filled it up so it has a full tank of gas. I had the spark plugs only changed in july because I took it to auto zone and the put it on the machine and said that’s what I needed. I do like the advice that you gave me but I do not know where the vacuum line is? Should I take it back to the same shop and inform him of what you said? Please help.