Problem with my 2001/ Pontiac / Grand Am
2.4 L
GM Computer codes = no
Changed spark plugs
Work done to repair this problem = changed spark plugs
GM tech = JK
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.
JK:
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.
Visitor:
The help you gave me was great. I checked the plugs again and they had black sut on
them and I also noticed a new symptom. The accelerator felt like it had pressure when
you would start out but the the pressure would decrease alot. 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,
2.4 L
GM Computer codes = no
Changed spark plugs
Work done to repair this problem = changed spark plugs
GM tech = JK
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.
JK:
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.
Visitor:
The help you gave me was great. I checked the plugs again and they had black sut on
them and I also noticed a new symptom. The accelerator felt like it had pressure when
you would start out but the the pressure would decrease alot. 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,
Other Repair
Questions
Questions
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.
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.
Answer: 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 done.
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 done.
