Grand Cherokee

Check Engine Light due to cylinder #3 misfire on Jeep Grand Cherokee

Problem Description and Possible Solution

A Check Engine Light may illuminate indicating a "Cylinder #3 Misfire." This normally occurs in hot weather after the vehicle has been driven, parked for ten to twenty minutes, and then restarted. Heat from the exhaust vaporizes fuel inside the #3 fuel injector and causes the misfire. Installing an insulator sleeve normally lowers the temperature enough so the fuel will not vaporize.

Problem Data
RepairPal Verified
Average mileage: 142,113 (80,000–240,326)
Engines affected: 4.0L 6 Cylinder, 4.7L V8
10 model years affected: 1999, 2000, 2001, 2002, more2003, 2004, 2007, 2009, 2010, 2011
63 people reported this problem
Viewing 1 - 19 of 19 comments
once engine warms up it starts missing, code reads 3rd cylinder. I have replaced coil pack, sensors, and other things nothing fixes it. I can put jeep in neutral turn it off & on again and jeep runs fine for a while. I had a mechanic take the coil pack off and put it in the freezer cool it off, put it back on jeep, and the miss stopped. This has been going on for 2 years and something happened while driving so now the engine runs so ruff I have had to stop driving it. I see that this is a common problem talked about on several jeep forums, does anyone have any answers?
3rd cylinder misfire by cool motor start, after running it for 15 minutes and start it again car runs normally,
if motor oil is below add car starts normal in the morning by cool motor,

What's the problem ?,have change coil-rack ,clean injectors, change all map-sensors and vacuum lines and walves
I have seen the same problem with my jeep, had the car for about 9 years now and other than now it was a great car. the car struggles to start in the morning will start on the second sometimes 3rd try. and it will run fine for about 20 minutes, will start pulling alittle like it's not getting enough gas. the bigger problem seems to be if i stop and turn off the car if I restart before it completetly cools down is will not only strugle to start but run rough and will almost all the time have missfires. I have repalce fuel pump, injectors, plugs and coil pack it has made a small improvement but still continues to have the problems. If i let it cool down completetly and them start, it will run fine for 20 minutes again.
I have random misfires in all 6 cylinders, especially in #4,#5 and #6. I also have a small evap sys leak that has been inspected down to removing the hitch,bumper and gas tank. I ran out of money and still have the problems. I bought it this way
after i changed the spark plugs first it was cylinder #5 misfire so I changed the coil pack now its saying cylinder #3 what do I do next?????
The computer showed a misfire #3. Changed the fuel injector, the power pack twice, a new clip that goes into the paperback, and the spark plug. All that time and money and the problem continued. The problem was the fuel injector was defected. I'm glad it was under warranty. I love my jeep grand cherokee
Engine misfires in warm weather after being driven several miles. Problem goes away after vehicle cools down. No solution found by dealership at this timr
Tried that...still does the same thing. Does a weird idle and will not let you go more than maybe 10 miles an hour if that. Replaced like the service noticed said...still doing it.
after running for a while and shut engine off for few minute and try to restart it is hard to start . when it starts it misfires.for about a minute then run fine. if i let it set for awhile (15 min or so) it does fine.
Too many problems at the time, won't be repairing her. Problems with MY 4.7 L, V8 JEEP: 1. Torque converter problem. 2. Buildup inside the engine because the fluids aren't flowing freely throughout, due to broken parts in engine. 3. Line pressure malfunctions 4. EVAP emission leak (well, of course!) 5. Rear right wheel speed and signal malfunction 6. Electrical issues up the butt, this JEEP randomly has the car alarm going off.

Whoever owned JEEP before I did not do their part in caring for the vehicle, unfortunately. I loved it for the 88 days I had it, but will be nothing but a money pit from here on out so I have to let her go.
Rough idle, rather engine is cold or hot.code misfire cylinder #3 #4 .hesitation and
How can I fix this problem?
My Jeep is a 3.7L, I put 4.0L because 3.7L was not an option. Anyways, my Jeep has been doing this frequently and it is driving me crazy. I have had to literally cut my car off and back on in the middle of traffic.
P0203 Cylinder 3 injector misfire. Reset code and have replaced the cylinder. Still happens.
I get the cylinder misfire on my 2010. Only when it gets hot out side. I drive it and then after it sits it comes back on. I'm going to try all different advice from everyone. Hope this helps. I'll update when something works.
Engine running very rough then check engine came on. Checked problem with OBD-2 and indicated cylinder 3 misfire. Weather very warm.