7.4 Starting issues

[BURRIS490]

I have a 2000 k3500 with the 7.4 vortec When it's cold, or hasnt been ran, she fires right up no problem. But if the truck has been running, or Its about 75° or hotter out, it takes forever to turn over. No odd symptoms when it does fire though. Any suggestions before I blindly throw parts at it? It has been like this for several years

 

[454cid]

I had a similar issue. It started much better if it had been sitting for quite awhile, or started shortly after being shut off. If started in between somewhere it would often start very hard, but even when it started ok, it wasn't great. I had always heard that the OEM injectors were a bad design, and would leak, so I assumed that was it, since it wouln't hold fuel pressure very well. Putting the pedal to the floor (clear flood mode) while starting the truck never helped, Though.

Just this last summer, the fuel pump started dieing. It was a dealer purchased replacement in 2004. I bought a Denso pump through Advanced Auto online. I was surprised to find that the truck started almost perfectly after that. A few months later I ended up replacing the starter with a new AC Delco purchased through Rockauto, and that got it even closer to perfect.

So in short, I had a tired fuel pump, and a tired starter motor.

 

[BURRIS490]

I'll definitely give the fuel pump a shot! My starter is still pretty new though. I'll also check out what my fuel pressure is looking like, and maybe replace those injectors as well if its needed. Thanks for that input!

 

[454cid]

I'll definitely give the fuel pump a shot! My starter is still pretty new though. I'll also check out what my fuel pressure is looking like, and maybe replace those injectors as well if its needed. Thanks for that input!

How many miles are on the truck?

 

[BURRIS490]

How many miles are on the truck?

About 150k

 

[454cid]

About 150k

That's not that much for a 19 year old truck. I'd start with checking the fuel pressure, like you mentioned. If you replce the pump make sure you get a good brand, and change your harness over to the flat four connector, instead of the square four... a lot of pumps come with the new pigtail.

I wouln't bother with the injectors unless you still have an issue. I have almost 290K miles on my originals.

 

[BURRIS490]

That's not that much for a 19 year old truck. I'd start with checking the fuel pressure, like you mentioned. If you replce the pump make sure you get a good brand, and change your harness over to the flat four connector, instead of the square four... a lot of pumps come with the new pigtail.

I wouln't bother with the injectors unless you still have an issue. I have almost 290K miles on my originals.

Awesome. Thanks for the input I'll definitely check that out and check out that pump. She used to be an oilfield truck, so its had it pretty rough. I'm slowly working on fixing it up