why does 99 gmc jimmyloose power the gas i give it . .
my 99 jimmy idiles fine and runs fine going 20 to 30 mph but when i give it gas
it wants to cut .or idiling when i push on the gas it cuts out.
It may be a fuel issue or a spark (electrical) issue. i would suggest checking the fuel pressure at the Schrader Valve on the intake manifold. Fuel pressure should be 56 to 63 lbs. if this is a V6 or a V8 engine. Once fuel pressure builds up, turn the key off. The fuel pressure should not drop more than 5 lbs. in 3 minutes.
checked fuel pressure. running about 55 lbs. dropped about 4 lbs in 6 min.
Boy, that is border line readings, but not your problem. I am thinking the coil is bad. That can be tested at Auto Zone.
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