2001/ Pontiac / Grand Am Changed spark plugs.
Work done to repair this problem = changed spark
plugs. Question = The car intermittently misses
under normal driving conditions every once in a
while. Changing the spark plugs makes it go away
but a day or so later it comes back.

If changing the plugs helps, i would
look closely at
the plugs that were removed. Make sure they all
seem the same color. If one is oil fouled, or looks
a little greenish or orange (depending on which
coolant is in the system at this time) this would
indicate an internal engine problem. If one is
totally black, this would indicate a rich fuel
condition which may be caused by a faulty injector
or is more than one is black, then i would suspect
a leaking fuel pressure regulator.
If plugs look OK, you may have a problem with the
ignition coil housing cover or one of the plug
boots. The cover is the black plastic housing
under the aluminium cover you remove to replace
the plugs. An ohm meter check will sometimes
indicate this housing is faulty. Also possible the
ignition module itself is stating to fail.

A sticking injector is also a possibility.
An injector
balance test may be needed.
You need to find out which cylinder is missing
when the condition is occurring. A scanner with
live engine data stream is the best way to see this.
That would at least narrow down to 1 cylinder to
concentrate on.

The help you gave me was great. I checked the
plugs again and they had black soot on them and
I also noticed a new symptom. The accelerator felt
like it had pressure when you would start out but
the pressure would decrease allot. I replaced the
fuel pressure regulator and now there is pressure
and no skipping at higher speeds, also the
hesitation at takeoff has gone away. Thank you.
1995 Pontiac Grand am SE 3.1l.
Replaced spark plugs + wires.
Question: My pontiac grand am is running really rich and getting
around 8MPG. Just recently was working on it and this is what we
checked so far. Ignition coils - good no cracks good resistance
Regulator valves - Hooked up a vacuum at 30 PSI no leaks.
Replaced the spark plugs because they were black at the tips and
because the gap in them are to wide. One of the o2 sensors, but I
am not getting any error codes on anything.
If "Regulator Valve" is referring to the fuel pressure regulator,
and you are sure the fuel pressure regulator is not leaking, then i
would next check fuel pressure. Make sure it is not too high.
That would causes running rich.

If the front
oxygen sensor was not the one that was replaced,
replace it. It is possible that you got some bad gas and the
injectors are leaking. An injector balance test would need to be
2001 Grand Am Misfire- Many Parts Replaced

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