Random misfire at cold starts and idle
07-16-2013, 01:34 PM
#1
Thread Starter
Join Date: Feb 2013
Location: UAE
Posts: 47
Random misfire at cold starts and idle
Hey guys,
Lately i have been experiencing a misfire at idle only.I have the torque app and I get between 1 to 20 misfires at each start-up .I can feel most of them . Now i have a faulty injector in cylinder #5 which is causing almost all the misfires and I'm going to change or clean it soon. My question is that the other cylinders are also misfiring randomly but i cant feel them , i only notice the misfires in the app . For example i get 1 count for cyl #1, 2 counts for cyl #8, the next time neither cyl #1 or #8 misfire and so on. I've changed the spark plugs recently , checked the ignition coils, changed the fuel filter, ran a couple bottles of FI cleaner which helped for few days . The car has almost 105k miles on it. Waiting for your replies.
Thanx in advance .
Alam
Lately i have been experiencing a misfire at idle only.I have the torque app and I get between 1 to 20 misfires at each start-up .I can feel most of them . Now i have a faulty injector in cylinder #5 which is causing almost all the misfires and I'm going to change or clean it soon. My question is that the other cylinders are also misfiring randomly but i cant feel them , i only notice the misfires in the app . For example i get 1 count for cyl #1, 2 counts for cyl #8, the next time neither cyl #1 or #8 misfire and so on. I've changed the spark plugs recently , checked the ignition coils, changed the fuel filter, ran a couple bottles of FI cleaner which helped for few days . The car has almost 105k miles on it. Waiting for your replies.
Thanx in advance .
Alam
07-16-2013, 02:10 PM
#2
Gentleman's Relish
Join Date: Feb 2005
Location: AZ
Posts: 13,090
Depends on what's causing the misfire. Does your app tell you if it's spark related or fuel related?
Fuel related: Whatever impurities caused the misfire in cylinder 5 are probably still stuck in the injector and somewhat stuck in the other injectors. FI cleaner only works if the material can be broken down small enough to pass through the injector. If you've already ran a couple of them through, I'd say your next bet is to replace the injectors.
Spark Related: How old are the plugs? If you don't know, it wouldn't hurt to take one out and see the condition. Perhaps they've never been changed?
If you take a plug out, follow the TSB to prevent issues.
TSB PDF:
http://www.phila.gov/fleet/Warranty%...-06%20FORD.pdf
Fuel related: Whatever impurities caused the misfire in cylinder 5 are probably still stuck in the injector and somewhat stuck in the other injectors. FI cleaner only works if the material can be broken down small enough to pass through the injector. If you've already ran a couple of them through, I'd say your next bet is to replace the injectors.
Spark Related: How old are the plugs? If you don't know, it wouldn't hurt to take one out and see the condition. Perhaps they've never been changed?
If you take a plug out, follow the TSB to prevent issues.
TSB PDF:
http://www.phila.gov/fleet/Warranty%...-06%20FORD.pdf
07-16-2013, 07:21 PM
#4
Thread Starter
Join Date: Feb 2013
Location: UAE
Posts: 47
Depends on what's causing the misfire. Does your app tell you if it's spark related or fuel related?
Fuel related: Whatever impurities caused the misfire in cylinder 5 are probably still stuck in the injector and somewhat stuck in the other injectors. FI cleaner only workshop if the material can be broken down small enough to pass through the injector. If you've already ran a couple of them through, I'd say your next bet is to replace the injectors.
Spark Related: How old are the plugs? If you don't know, it wouldn't hurt to take one out and see the condition. Perhaps they've never been changed?
If you take a plug out, follow the TSB to prevent issues.
TSB PDF:
http://www.phila.gov/fleet/Warranty%...-06%20FORD.pdf
Fuel related: Whatever impurities caused the misfire in cylinder 5 are probably still stuck in the injector and somewhat stuck in the other injectors. FI cleaner only workshop if the material can be broken down small enough to pass through the injector. If you've already ran a couple of them through, I'd say your next bet is to replace the injectors.
Spark Related: How old are the plugs? If you don't know, it wouldn't hurt to take one out and see the condition. Perhaps they've never been changed?
If you take a plug out, follow the TSB to prevent issues.
TSB PDF:
http://www.phila.gov/fleet/Warranty%...-06%20FORD.pdf
Stock ones.
07-17-2013, 11:50 AM
#5
3rd Gear Member
Join Date: Oct 2009
Location: Utah
Posts: 730
Check your plugs for being loose. Wouldn't hurt to pull them out and make sure they aren't fouled. Three forum members so far over the summer have had misfires from loose plugs when other possible causes have been ruled out.
07-17-2013, 04:02 PM
#6
5th Gear Member
Join Date: Jul 2009
Location: Delaware
Posts: 2,215
What FI cleaner are you using? Seafoam has fixed misfires for a lot of Mustangs. Also, when checking for fouling check the gap. Maybe one got dropped and the gap has changed. Do you have a code reader? (I don't know what the Torque app does)
07-17-2013, 07:49 PM
#7
Thread Starter
Join Date: Feb 2013
Location: UAE
Posts: 47
Im using STP and one time ive used valvoline , We dont have seafoam here in UAE. Im using the motorcraft plugs which have closed tips . No codes and car is running great .
Thread
Thread Starter
Forum
Replies
Last Post