misfire

[96pontiac]

1996 grandam 2.4 1 and 3 dont fire. changed coils ign control module plug caps .still have problem .only show misfire code

[rixGAphx]

1996 grandam 2.4 1 and 3 dont fire. changed coils ign control module plug caps .still have problem .only show misfire codeHave you changed spark plugs?

One plug, completely broken internally, will not only prevent itself from sparking but will also prevent sparking of its 'paired' sister plug.

[HeyDace]

Are you sure its a secondary ignition problem and not an injector problem?

[ENGGUY]

compression test?
CPS?
Codes?

[96pontiac]

plugs have been changed coils, coil housing,plugs, ignition control module,plug wires,still same

[96pontiac]

getting gas even swapped injectors same results

[rixGAphx]

Is this a continuous condition, i.e., the engine is only running on 2 cyls?
Or is there just random poor performance, and the 'puter returns the misfire codes P0301 and P0304?

I thought your engine didn't have plug wires, only some kind of boots with a spring or such to carry the current from coil to plug.

Could be the wiring to the injectors rather than the injectors themselves, though I don't know why it would associate with both cylinders.

I recall reading a post/thread here within the past 4-6 weeks, with the same symptoms.
Turned out to be a failed Fuel Pressure Regulator, allowing fuel to seep into the intake manifold from the leaking FPR diaphragm via the vac tube.
For some bizzarity of the intake design, the minor leak only affected the two outer cylinders, not 2 and 3.
Definitely use a vac tester to check that tube to see if the diaphragm holds vacuum.

Hope this helps,
-Rick