- Joined
- Aug 7, 2007
- Messages
- 1,507
- Points
- 3,101
- Age
- 62
- Vehicle Year
- 1986
02'
- Transmission
- Automatic
A friends has this intermittent miss/misfire on his 97 f150 with 4.2v6.
history:
earlier this summer a scan showed a misfire on #4 cylinder (code p0304)...he took to a repair shop and discovered that there was a leaking head gasket, which explained some missing coolant every once in while.
To fix, the heads were removed checked , planned and new injector on #4 cylinder, new plugs and wires ...to the tune of +$1500......and more recently coil pac.
he still has this intermittent miss/ misfire..not really happy, nor anxious to spend more.
tried to help him out and ran codes with my cheap scanner....after it finally tripped the CEL on the dash....came up with...you guessed it....misfire on #4 cylinder. After digging thru the scanner menu a bit, it did show the at 3 of the 8 precheck came up incomplete.....those missing are, evap sys, O2 sensor, and O2 sensor heater. we did give the MAF sensor a quick spray with some cleaner. didn't help.
he mentioned that it seems to be worse as weather cools and cold starts....but not consistantly holding true to that, as it will still miss fire when fully warm.
surprised that with all the work previously done that new O2 sensors were not replaced....so tried to encourge him to return it to the place that did the initial work & show the missing systems check...see if they can narrow the options.
thought I'd post this here to see if others have run on to this and might give some direction to the cure.
thanks in advance
history:
earlier this summer a scan showed a misfire on #4 cylinder (code p0304)...he took to a repair shop and discovered that there was a leaking head gasket, which explained some missing coolant every once in while.
To fix, the heads were removed checked , planned and new injector on #4 cylinder, new plugs and wires ...to the tune of +$1500......and more recently coil pac.
he still has this intermittent miss/ misfire..not really happy, nor anxious to spend more.
tried to help him out and ran codes with my cheap scanner....after it finally tripped the CEL on the dash....came up with...you guessed it....misfire on #4 cylinder. After digging thru the scanner menu a bit, it did show the at 3 of the 8 precheck came up incomplete.....those missing are, evap sys, O2 sensor, and O2 sensor heater. we did give the MAF sensor a quick spray with some cleaner. didn't help.
he mentioned that it seems to be worse as weather cools and cold starts....but not consistantly holding true to that, as it will still miss fire when fully warm.
surprised that with all the work previously done that new O2 sensors were not replaced....so tried to encourge him to return it to the place that did the initial work & show the missing systems check...see if they can narrow the options.
thought I'd post this here to see if others have run on to this and might give some direction to the cure.
thanks in advance
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