Need help with my first truck!

[Jaxson Renton]

I recently bought a 1998 Silverado with the 350 knowing it had some problems with “misfiring” but I didn’t know the causes, I got the truck for a good deal and it’s in great condition other wise, 150k miles if I remember right. anyways here are a few things I’ve noticed driving it on a test drive

Took 2 cranks to start up

Motor shakes on idle

Idles hard

Shakes when shifting

Looses lots of power when releasing pressure on gas pedal

Abs light on, check engine came on a few minutes into drive 

Has the 350 with cold air intake, 2 cherry pack exhaust

 

ive replaced the rotor cap and rotor and added sea foam. Both had no help really. If someone could show me how to upload a video of it running I think I could explain this way better.. but if anyone has any ideas please let me know 

[asilverblazer]

Check codes, with the engine light on it can narrow down the diagnosis, otherwise...

 

Check/replace

Plugs

Plug wires

Fuel pressure

Vacuum leaks

Compression

 

ABS light on is not related to engine performance.

 

Extended cranking makes me lean to lack of fuel pressure on start up - confirm the fuel pump is priming on key on.

 

Cold air intake - is the Mass air Flow Sensor present clean and connected?

 

Further thoughts based on "when releasing pressure on gas pedal" sounds like the engine is having trouble understanding the air intake.

 

 

Edited September 24, 2021 by asilverblazer