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  • 1996 - 2004 SN95 Mustang -General/Talk-
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Multiple misfires, I need some help

  • Thread starter Thread starter Silvestris
  • Start date Start date Apr 22, 2012

Silvestris

New Member
Nov 29, 2011
28
0
1
Crown Point, Indiana
Apr 22, 2012
#1
  • Apr 22, 2012
  • #1
Here's the story, I know I did something stupid, don't flame me out for it because I need help. Yesterday, I was washing, waxing, and detailing my car. Did the engine bay by spraying it all off with water and wiping down all the black plastics (including my CAI) with tire shine. I put forth an effort to not get my air filter and battery all wet. I let it dry for a few hours, start it up and it's just fine. Pull out of my drive, gave it some throttle and spun the tires a bit to get the tire shine off the tread. Everything seems perfectly normal until about a quarter mile down the road. I take a turn and my engine stalls. Wouldn't want to start back up again. Gave it a few more tries and it finally started. I could see out my rear view that every time I reved the engine, thered be a plume of white smoke. I drove to a parking lot, let it idle, and noticed it was idling a little rougher than usual. Turned it off, turned it back on, and now I have a CEL. Drove it back home and noticed that when I give it throttle, I heard popping noise. I thought it was running rich and backfiring. This morning I noticed it was coming from the intake, not the exhaust. Last night I pulled 1 code. P0171, bank 1 too lean. This morning I got 5 more. P0113 (IAT sensor circuit high output), P0302 (miss in cylinder 2), P0306 (miss in cylinder 6), P0307 (miss in cylinder 7), and C2500. I cant figure out the last one. I sprayed down my MAF with MAF cleaner, same with the IAT. My MAF counts are about 180 at idle, but it bounces up and down quite rapidly probably because of the misses. I checked for vacuum leaks and it seems ok, my IAT sensor seems to work fine. What the hell could I have messed up?
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Apr 22, 2012
#2
  • Apr 22, 2012
  • #2
...engine bay by spraying it all off with water...
Click to expand...

Pull the COPs or plug wires (don't know the year; 96-98 will have used coil packs with individual plug wires and 99-04 used coil-on plug (COP) ignition) and check down in the sparkplug wells for water.

Use compressed air to blow out any water and dry things out. Dry the insides of the COP/plug wire boot. Smear a bit of dielectric grease into the boot.
 

Silvestris

New Member
Nov 29, 2011
28
0
1
Crown Point, Indiana
Apr 22, 2012
#3
  • Apr 22, 2012
  • #3
I've got a 96 GT. I'm getting spark to the plugs, but I didn't look for water.
 

Silvestris

New Member
Nov 29, 2011
28
0
1
Crown Point, Indiana
Apr 22, 2012
#4
  • Apr 22, 2012
  • #4
Just did that. Seemed to help a bit, and there were no codes until I held the RPM at 3000 for a couple seconds. Now it gave me P0171 and P1000.
 

Silvestris

New Member
Nov 29, 2011
28
0
1
Crown Point, Indiana
Apr 22, 2012
#5
  • Apr 22, 2012
  • #5
I do notice that I'm getting a lot of water in my exhaust. It's about 55 degrees out, engine is up to about 170 degrees, and I'm seeing steam and puddles of water at my exhaust.
 

Silvestris

New Member
Nov 29, 2011
28
0
1
Crown Point, Indiana
Apr 23, 2012
#6
  • Apr 23, 2012
  • #6
Anybody? I really need help here. I'm going to do a compression test but other than that I'm totally clueless.
 

Silvestris

New Member
Nov 29, 2011
28
0
1
Crown Point, Indiana
Apr 23, 2012
#7
  • Apr 23, 2012
  • #7
Did a compression test. Took all plugs out, cranked the engine for 5 compression strokes each.
Cylinder 1-150psi
2-140
3-150
4-140
5-130 on 1st try. Sounded like it missed the last 2 compression strokes. 2nd try got 150
6-140
7-150
8-110 on 1st try. sounded like it missed the 1st compression stroke. 120 on the 2nd try, 3rd try 120, 4th try got 125 with 6 compression strokes.

Here's my spark plugs starting with 1 on the top left, 8 on the bottom right. They don't look terribly happy for being a few months old.
 
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