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
4,749 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.

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

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?

Was this

answer

helpful?

Yes

No

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

MASTERTECHTIM

MECHANIC
4,749 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?

Was this

answer

helpful?

Yes

No

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.

Was this

answer

helpful?

Yes

No

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