1997 chev silverado

[walleye29us]

4 wheel drive,5.7 liter, 149,000 miles. I was driving all over this morning with the truck running perfect, Im waiting at a stop light and all of the sudden the truck starts shaking and would barely stay running. Light turns green and i barely can get up to 30mph. I limped it home. It feels like its not running on a couple cylinders. It seems to idle ok when in park or neutral, but has very little power when giving it gas in gear and it sputters and shakes like crazy! What could cause this? Thx in advance!

[Jeremy airjer W]

Was the check engine light on and flashing?

[walleye29us]

The light didnt come on till i got home. It was not flashing,but it might have if i drove any further.

[Jeremy airjer W]

Check to see what the codes are. That will give you a good idea of where to start.

[walleye29us]

I knew you would say that! haha. thx.

[Darrell68]

The symptoms sound like my Buick did when a power pack went out.Might check that or maybe the fuel pump. Hope it helps...

[Jeremy airjer W]

The symptoms sound like my Buick did when a power pack went out.Might check that or maybe the fuel pump. Hope it helps...

If its the older 5.7 it will have a single coil and a distributor. If the coil goes dead the engine stops running.

The injection system should be a CPI unit. This unit requires a minimum fuel pressure of roughly 56psi in order for the mechanical injectors to work. Once fuel pressure drops below that psi the engine stops running.

[Macgyver55]

If its the older 5.3 it will have a single coil and a distributor. If the coil goes dead the engine stops running.

5.3s have always had individual coils...I'm thinking you meant to say 5.7

[Jeremy airjer W]

Yup, my bad. I changed it.

[walleye29us]

Thx Darrell68 for your input and ideas. I dont have a scan tool so i cant give you guys codes. If anyone has any more ideas without knowing the codes, i would love to hear them....Thanks guys!

[Jeremy airjer W]

Check with your local parts store. Many times they can or will pull codes for free. As of now you have been dropped off in unknown territory without a map. A lot of directions can be given but you don't know which one is the right one to follow. The trouble codes are the "you are here" on the map and depending on where you are will help decide on what directions you need.

You can purchase an inexpensive code reader just about any where for about $50. If you own a GM, Ford, Chrysler, or Toyota you'll get your investment back with just a couple of uses.

[walleye29us]

Ok thanks.

[BoxMN]

Not mechanic here, but that sounds like when my 98 k1500 was acting like that, it was that I put cheap plugs in it, and didn't replace wires at 100k. Put in the good ($$$) AC/Delco plugs and OEM wires and it fixed it. Learned my lesson.

Good luck.

[walleye29us]

Thanks for your input BoxMN. I dont have a clue what it could be so i limped it to the mechanic this morning. I will report back when i find out what it is.

[walleye29us]

UPDATE....Just picked up my truck. A new distributer cap was the fix. Running smooth now. Thx all who replied!