Number 1 cylinder missfire. What to do?

k_y86

Member
Joined
Sep 17, 2010
Posts
36
Reaction score
0
My number 1 cylinder is missfiring. Already chnged the coil pack. Car is already at 100000 miles. Spark plugs were changed with the bosch 4+ about 40000 miles ago. Fuel filter was replaced 30000 ago. Emptied a bottle of fuel injector cleaner into a full tank of fuel and the engine light continues to light up. Can somebody shed some light on this situation; do I need to replace the fuel injectors or is there a vaccum leak of some sort.
 

Revenant_SS

Full Access Member
Joined
Sep 16, 2009
Posts
54
Reaction score
0
Location
Eastern Canada
Swap #1 and #4 plugs. Chances are you'll get the misfire on #4 now because Bosch plugs are pure garbage. Replace with a set of AC Delco or NGK.

Put it to you this way. If I have a customer coming in looking for a tuneup, I would send them to another shop before we'd put Bosch plugs in.
 

bryson87

Full Access Member
Joined
Jul 21, 2009
Posts
7,371
Reaction score
0
Location
Pell City, Alabama
and if swaping the plugs dont work. swap the coil packs around also if it moves to the next cyl you put it on its the pack
 

k_y86

Member
Joined
Sep 17, 2010
Posts
36
Reaction score
0
no mods

Can you enlighten us on what has been done to the car as far as mods?

No mods have been done to this car just stock.

---------- Post added at 09:20 AM ---------- Previous post was at 09:18 AM ----------

Check the gap on the plugs

Can not gap the spark plug because it has the 4 of the things that you need to gap, not just one.

---------- Post added at 09:22 AM ---------- Previous post was at 09:20 AM ----------

Swap #1 and #4 plugs. Chances are you'll get the misfire on #4 now because Bosch plugs are pure garbage. Replace with a set of AC Delco or NGK.

Put it to you this way. If I have a customer coming in looking for a tuneup, I would send them to another shop before we'd put Bosch plugs in.

Already swaped spark plugs but with the #3 cylinder and it's still running the same.

---------- Post added at 09:25 AM ---------- Previous post was at 09:22 AM ----------

REplace fuel injector for that cylinder, make sure to change the o-ring and replace you MAP sensor.
Should fix it, just had same problem with #3 cylinder.

Dude I think your right because so far I've swaped the spark plugs and nothing so far. So where would the MAP sensor be located on a 2007 LS cobalt.
 

Spacey_stacey75

Full Access Member
Joined
Sep 24, 2010
Posts
210
Reaction score
0
Location
New Port Richey, Florida
well mine on an 06 was right under the intake, I think above the intake manifold

I went and bought the haynes repair manual so I could do this shit myself. I hate paying someone for something I can do.
 

Members online

Forum statistics

Threads
7,432
Posts
156,463
Members
4,340
Latest member
buttonsup
Top