1995 Mercury Mystique missing intermitantly

BLEEDINGKNUCKLES

MEMBER
1995 MERCURY MYSTIQUE
6 CYL
FWD
AUTOMATIC
47,000 MILES

Cylinders 1, 2 and 3 hit unevenly or weakly. Timing light shows erratic flash or none @ alll.4, 5 and 6 are fine. Noticable miss @ idle and when accelerating but smooth @ cruise. Checked coil pack and it's within spec.

Tuesday, May 27th, 2008 AT 10:59 PM

4 Replies

MASTERTECHTIM

MECHANIC
4,750 POSTS

If your not getting enough voltage output from the coil then you either have bad wires or a bad coil. The coil is either going to get a ground command for spark at the coil or not. If its getting the ground control to spark the coil and output is not what it should be I would suggest replacing coil, plugs and wires.

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Wednesday, May 28th, 2008 AT 7:18 PM

BLEEDINGKNUCKLES

MEMBER
3 POSTS

Thanks for the direction on that. Not much room to get to plugs 1, 2 and 3. And why just that bank when the corresponding cylinders of the three coils(4, 5 and 6) fire fine?

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Wednesday, May 28th, 2008 AT 11:52 PM

MASTERTECHTIM

MECHANIC
4,750 POSTS

Thats a good question and I wish I had a definite answer for you but I dont. I dont know whats going on inside the coil, I can assume maybe that side shares a ground inside the coil housing(this is purely a guess). Are you using a spark tester that tests coil output voltage?

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Thursday, May 29th, 2008 AT 5:41 AM

BLEEDINGKNUCKLES

MEMBER
3 POSTS

Nah.I'm old school. Grab the wires wet handed and measure how high I jump. Lol.I don't have a volatage output tester. Just looking @ the brightness of the inline spark tester.I ordered an OBD 1 code reader(numerical readout) 10 days ago but it hasn't shown up yet. Figured that it would at least verify which cylinders aren't hitting. Managed to squeeze a stheoscope probe between the wiring harness covers and intake manifold. All of the injectors are clicking evenly from idle thru about 2700 R's. Thanks again for your thoughts on this.

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Thursday, May 29th, 2008 AT 11:27 PM