Hey guys hoping you can help me here. I have an 87 s10 blazer 2.8 I bought a few months ago. I had the fuel pump and fuel filter replaced initially and was running fine until recently. Its starts right up and idles great while its just sitting, but once it starts to drive, its starts to putt putt and cut out and when I give it gas theres a pop that seems to be coming from under the airfilter/carb area and completely cuts out. I had the distributor, coil, pluggs, wiring all replaced but cant quite figure this out cause it runs so good in neutral. Also checked the gaps in the pluggs and they're at .45 wgphich seems fine to me. Very frustrating, mplease help

 

Is there a check engine light on? Also have you verified that there are no vacuum leaks? I'm not all to certain but I would also check the ecm.

 

depending on what pump they put in,could be the problem. sounds like a fuel issue.

 

Have you tried checking the EGR valve? It may need cleaning or replacing. Also, make sure your engine grounds are proper as that could cause your issues as well.

 

check ignition timing, fuel pressure and firing order. An injector problem would be apparent at idle, so would a vacuum problem. If ignition timing is too advanced it will idle extreamly smooth but once under load it will throw a fit. Low or high fuel pressure could explain it. If the firing order got messed up it "could" idle fine, then run out bad. Happened to my grandpa's impala, idled great but would breathe fire if you drove it. Lol. Timing should be at 0 degrees