ramsey1412

I have a 99 Silverado 1500. ive only got 85,xxx on my truck. it started happening almost instantly where my truck would just turn over with two or three turns of the key then would fire up. I have no idea what it is. The Chevrolet dealer near me said it was most likely my fuel pump but I don't think it would just all of a sudden go out. Plus I don't really have much trust for dealer mechanics because they are really out for money. If anyone has any ideads what it could be that would be great!!! Thanks

RB Auto Service

I own a GM Specialty shop. And unfortunately there is nowhere near enough information in your post to give you any meaningful answer. What testing have you done? What test equipment do you have access to? If you are unable to do testing on your own is there not an independent GM specialist in your area that has a good reputation? I would love to help you but this is a modern vehicle and I can list a half dozen possible causes without even trying that hard. Some of which can be quite expensive. If that was the only information I had and I was forced to make a guess. My first test would probably be the battery. Low voltage I believe under 9.6v when cranking even momentarily changes the fuel strategy and can cause a hard start. Cranking speed may seem and sound sufficient. But jump starting the vehicle will result in a normal start. If the battery proved to be healthy I would probably scan all on board modules for codes and start a methodical approach of determining what is missing when it won't start.

ramsey1412

You sound very informed. the truck turns over normally it seems it just will not start. I know I need to take it to a shop and get it tested but ive had bad experience with the GM nearest to me. I kind of enjoy figuring it out while I fix something I just don't know where to start. I just recently recharged my a/c and that's about when it started. I do need to change the belt and tensioner pulley because it slips and squeals ever since I filled it but iwas told by GM that would have nothing to do with it.

tech2

the only symptom is a long crank time after sitting?

does the vehicle start normally if you shut it off then restart it immediately?

ramsey1412

yes but if it sits for 20 minutes or half hour it does it again

RB Auto Service

Next time try cycling the key on and off several times before attempting to crank. This will pre-prime the system if it isn't holding pressure. If cycling the key helps I would strongly suspect the problem is in the fuel system. The pump will run for 2 seconds to prime so hold the key in the on position for that long when cycling. I still say test the battery. It sounds crazy but I have seen it dozens of times on late model small blocks. Cranking speed will seem normal but the voltage will be too low for the electronics to operate properly.

tech2

if you want to confirm a bad check valve in the fuel pump assembly; install a fuel pressure guage, prime the fuel system by cycling the key to run. Watch for a pressure drop.

Extenal check valves can be install in the fuel line to repair this... just get used to cycling the key.

ramsey1412

ok great ill try that tomorrow and let you know how it goes!

therewolf

Hey ramsey1412, Welcome to the Chevrolet Forums.

Google or thread search CPS- Crank Position Sensor.

I'm assuming, of course, that you already changed both your

battery cables, and your engine to firewall ground strap.

WarrantyWorkSucks

If it's a hard start a common problem I have ran into is fuel pressure regulators especially on some of the older model Silverados. Try holding the gas pedal to the floor and see if it starts right up. I also too like the idea of testing the battery start with simple tests and work your way up to more complex.