Vehicle = 1998 GMC K-1500 4X4, 305 V8, Automatic.

Good morning everyone...
Here's the deal, up until recently my truck has run great, a couple of weeks ago it started getting really bad on fuel. Now, as you press on the throttle, it dogs for a bit until you press the pedal down far enough then the motor takes off normally. I immediately thought it was the TPS so I changed it out....NO FIX. A friend of mine was saying that one of his buddies had the same problem and it ended up being the EGR.
If anyone has any suggestions I would love to hear them.
Thanks again

Jed Ashby

Possibly a leaky fuel pressure regulator. I'd check the fuel pressure.

Sounds like 52degrees has got this one down. California smog tech? Are you an L1, too? I am, only 1 of 2 in this county (what can I say, we don't have any emissions testing here yet, let alone IM240).
That's where I would start, too. The condition will get progressively worse, as the plugs get more fouled. Replace them after you've fixed the root of the problem. A sticking EGR would cause a rough idle, but would also cause your brake pedal to be hard because of lack of vacuum. However, your truck is OBDII, check codes first, and go from there. The diagnostics on that truck are very good, guessing is just pissing in the wind. A leaking regulator would set two codes, rich condition bank one, and rich condition bank two. I know the lean codes for this are P0171 and P0174, don't remember what the numbers are for rich, but is may be P0172 and P0175.

In Kalifornia, you have to have your L1 to obtain and maintain a smog license. No IM240, it's a two speed test. 50/15 (50% load at 15mph) and 25/25.

The code set would more likely be a P0174 since the intake runners for bank 2 are right under the regulator, unless I am thinking of the way the v-6 injector assembly mounts. They are similar, so I can get them confused in my head.

If the bogging continues and you fixed the regulator (presuming it was leaking) check for a P0300 and P140x codes. These together indicate a likely plugged catalyst.