The gap needs to be checked before instillation.
Maybe when they put the spark plugs in they were not gapped right or they maybe the wrong spark plugs.
Yes , should be checked Yes sometimes in shipment they get knocked out of seting
The spark plug gap for a 2004 Chevrolet Suburban should be set at .040 inches. The new spark plugs are pre-gapped and do not need adjusting.
New spark plugs do not necessarily come already pre-gapped for the application. Remove the spark plugs and gap per specifications. If you are not sure what the gap should be, call the auto parts store where you bought the plugs and ask them.
The spark plug gap for a 2000 GMC c3500 with a 7.4 liter engine should be set at .045 inches. New spark plugs should not need to be gapped as they come preset from the factory.
I'd suggest pulling the new plugs and checking the gapping. Replacing properly gapped plugs with improperly gapped ones can cause a loss of power. And if you replaced them yourself with "pre-gapped" plugs, check them anyway. A lot of the "pre-gapped" ones are incorrect. If you are a do-it-yourselfer just pop a few out and check the gapping. If not, take it back to the garage that did the work and tell them of the problem and ask them to check.
The proper spark plug gap for a 2002 Yamaha YZ250 is .024 inches. New spark plugs usually come pre-gapped, however.
"Spark plugs are typically designed to have a spark gap which can be adjusted by the technician installing the spark plug, by the simple mechanism of bending the ground electrode slightly to bring it closer to or further from the center electrode. The belief that plugs are properly gapped as delivered in their box from the factory is only partially true, as proved by the fact that the same plug may be specified for several different engines, requiring a different gap for each. It can depend on the engine: new spark plugs might be pre-gapped for a V-8 engine, installing all 8 plugs unchanged; however, for a 6-cylinder engine, all (6) plugs would be re-gapped." strait from wikipedia. http://en.wikipedia.org/wiki/Spark_plug
Possibly in need a new spark plugs... I had a Honda that did this,and new plugs,it was running like new....
New plugs are pre-gapped, but if you are reusing old plugs then Gap=0.054 Good Luck and Remember.Change Your Mind, Not Your Oil.Use the First In Synthetic Motor Oil's.See My Bio For more information.
You will need the correct replacement spark plugs, a spark plug socket, and a screw driver. The new cars have the spark plugs concealed and you might have to open the cover over the engine to access it, which may require addition tools
The spark plug gap for a 1970 Blazer 350 is .035. Check new plugs for correct gap even if they come pre-gapped.