Engine misses

[e.p.]

Hi;

I have a 2000 Silverado 4.8l automatic approx. 70k that has a miss when its under load. Idles good in park and accelerates ok. When sitting at a light in drive the engine will miss and when under load and accelerating in overdrive at highway speed it misses until the transmission downshifts. Fuel presure regulator has been changed for hard start before. I just changed the plugs with stock AC Delco to try and correct this problem with no luck. Any help is greatly appreciated.

Thanks

[bigbuck]

I have the same problem with my 99 4.8 manual transmission except when i run it up between 3500-4000 rpm the engine starts to break up.

[bigbuck]

put new plug wires on mine problem gone. I cant beleive bad wires made it run that bad. When i was younger i had cars with wires so bad it looked like a light show at night under the hood and never ran that bad.

[Jasonsupafly]

Wires !

[JeridJohnson]

hmm.... I have what sounds like a similar prob with my 5.3L silverado..

 

Sometimes I get a misfire condidtion and the Service Engine Soon light comes on.. I notice that the engine is weak and hesitates on acceleration.. It comes and goes like it is on a switch.. Hesitation.. then straight to power.. Plugs have been replaced and I guess I'll be looking for a set of plug wires tomorrow.. Sure would beat taking it to a mechanic.. (I hate taking my car to the shop.. I am never satisfied)

 

Should I go with factory plug wires or is there a good replacement that I can pick up from the local auto supply?

 

Thanks,

Jerid

[OUMike]

Should I go with factory plug wires or is there a good replacement that I can pick up from the local auto supply? 

 

<{POST_SNAPBACK}>

 

 

 

Wires and plugs are the one thing you shoudln't go cheap on. Get the Delcos.

[Black Bart]

I had the same problem with my 94 Silverado , the wires

were about a year old , but, like oldwrench says (Wires)

after cleaning and gapping the plugs, I checked the wires

with an ohm meter and found one open.

[e.p.]

Hi;

Thanks for the help. I will get a set of wires shortly and change them. Hopefully that will cure the problem.

Thanks.