Help please!!!???!!!???!!!

[Z71rider88]

My little brother has a 98 Silverado has the 5.7 vortec 350 in it some days it starts fine other days it will turn over and not start somebody told me check the timing I did that and it’s good the fuel pump is kicking on as well that’s fairly new I’m thinking crank position sensor maybe going bad anyway to check that and does anyone have any other ideas I appreciate it thanks in advance! Also has a new starter as well

 

[RedLeader289]

Fuel, air, spark. You're getting the first 2, so check for the third. pull the #1 spark plug and ground it to the block. turn the engine over and have someone look for the spark (much easier in the dark).

 

[Z71rider88]

Fuel, air, spark. You're getting the first 2, so check for the third. pull the #1 spark plug and ground it to the block. turn the engine over and have someone look for the spark (much easier in the dark).

Thanks I’ll try that and let you know what happens

 

[PeteyG708]

I sometimes have to hold my 98 in Start for about 5 seconds before it kicks up, and other times it is instant.

Check the distributor and rotor as well as spark plugs and wires. I notice that if it rains, it hets harder to start and runs like crap until it is warmed up.

Basically, what RedLeader289 said.

 

[tinfoil_hat]

Also be aware that you can't set the timing with a light the old fashioned way.

 

[Tom P]

Perhaps look into investing in a OBDII scanner. There are a lot of issues that can occur without throwing a CEL especially if they resolve themselves after a period of time. The scanner can provide you with live data such as fuel trims, O2 sensor inputs, spark advance, MAF, MAP and Throttle position, which will help in diagnosing an intermittent problem such as what you are describing. Just because the fuel pump is working, doesn't mean you don't have a fuel issue, so don't assume its spark.