Misfire Cyl 3 & Random Misfires
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From: N35°03'16.75", W 080°51'0.9"
Misfire Cyl 3 & Random Misfires
2002 TL-S. ~122k miles.
Normal maint, w/Mobil1 (or similar) synthetic. 93 octane gas all the time. Timing belt, plugs, etc., (105k service) completed at ~4/28/08 (66k miles).
Today got stuttering and flashing CEL on start up. Some stuttering after warmed up and no CEL. Later, cold start, got stuttering and CEL at ~45 MPH.
Codes pulled at Autozone:
P0303: Cylinder 3 Misfire
- Vacuum leak
- Ignition System
- Blocked/Faulty Injector
- Engine Mechanical
P1399: Random Cyl Misfires
- Blocked EGR Passage
- Valve clearance
What should I do?
TIA
Normal maint, w/Mobil1 (or similar) synthetic. 93 octane gas all the time. Timing belt, plugs, etc., (105k service) completed at ~4/28/08 (66k miles).
Today got stuttering and flashing CEL on start up. Some stuttering after warmed up and no CEL. Later, cold start, got stuttering and CEL at ~45 MPH.
Codes pulled at Autozone:
P0303: Cylinder 3 Misfire
- Vacuum leak
- Ignition System
- Blocked/Faulty Injector
- Engine Mechanical
P1399: Random Cyl Misfires
- Blocked EGR Passage
- Valve clearance
What should I do?

TIA
Bearcat! long time no chat! sad it has to be in this situation, tho.
for the EGR valve, you can unbolt the two bolts that hold it and pick off any carbon that is in there.
This should clear both codes, unless the car has been overheating. has the car been overheating?!
for the EGR valve, you can unbolt the two bolts that hold it and pick off any carbon that is in there.
This should clear both codes, unless the car has been overheating. has the car been overheating?!
Thread Starter
AZ Community Team
Joined: May 2007
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From: N35°03'16.75", W 080°51'0.9"
Bearcat! long time no chat! sad it has to be in this situation, tho.
for the EGR valve, you can unbolt the two bolts that hold it and pick off any carbon that is in there.
This should clear both codes, unless the car has been overheating. has the car been overheating?!
for the EGR valve, you can unbolt the two bolts that hold it and pick off any carbon that is in there.
This should clear both codes, unless the car has been overheating. has the car been overheating?!
OK, that's what I was hoping .... EGR Valve. I'll clean it and see how it goes.
Is it OK to drive for a day or so?
(TIA = Thanks In Advance you leg humper.)
it is okay to drive, as long as you dont mind the stuttering due to the EGR valve being blocked by carbon.
and you're slacking. check for white text!
Thread Starter
AZ Community Team
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From: N35°03'16.75", W 080°51'0.9"
Right - it is not overheating.
On the 2nd gen the EGR code is usually caused by the 6 ports that get clogged under teh cover. Id pull the top intake manifold cover off and look for blockages in that and the 6 holes.
As for the misfire, it could be the egr causing a false code, or it could be a coil on #3 going. (very common on these)
As for the misfire, it could be the egr causing a false code, or it could be a coil on #3 going. (very common on these)
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Thread Starter
AZ Community Team
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From: N35°03'16.75", W 080°51'0.9"
On the 2nd gen the EGR code is usually caused by the 6 ports that get clogged under teh cover. Id pull the top intake manifold cover off and look for blockages in that and the 6 holes.
As for the misfire, it could be the egr causing a false code, or it could be a coil on #3 going. (very common on these)
As for the misfire, it could be the egr causing a false code, or it could be a coil on #3 going. (very common on these)
Will do. If none of that works, I'll try the coil next.
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From: N35°03'16.75", W 080°51'0.9"
:grrrr:
Cleaned the EGR chases and holes - they were pretty grimy, but not fully blocked.
Could not clean the EGR Valve because I stripped one of the nuts and couldn't get it off.
Seems a little better, but not fixed and still getting hesitation and flashing CEL under throttle at ~45 MPH.
I'm going to check the coils and if OK, take it somewhere to get the EGR valve removed and cleaned.
Cleaned the EGR chases and holes - they were pretty grimy, but not fully blocked.
Could not clean the EGR Valve because I stripped one of the nuts and couldn't get it off.
Seems a little better, but not fixed and still getting hesitation and flashing CEL under throttle at ~45 MPH.
I'm going to check the coils and if OK, take it somewhere to get the EGR valve removed and cleaned.
Hey Bear, remove the coil from the #3 cylinder and see if it makes any difference in the idle rpm.
Pull that plug and see how it appears. Ya may want to buy one new coil and try it on that cylinder. Reset the ECU and see how it runs.
Pull that plug and see how it appears. Ya may want to buy one new coil and try it on that cylinder. Reset the ECU and see how it runs.
Thread Starter
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From: N35°03'16.75", W 080°51'0.9"
Thread Starter
AZ Community Team
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From: N35°03'16.75", W 080°51'0.9"
That only works if the coilpack is completely dead. You can try that and see what happens. You could also move that coil pack to a different cyl and reset the ecu and when the cel comes back on see if the misfire followed that coil pack.
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From: N35°03'16.75", W 080°51'0.9"
I've got to get the EGR Valve out and cleaned (or replaced) before anything else.
Looks like I'll need to take somewhere where they can get the nut I stripped off.
Hey Bear, did ya pull the #3 plug and check it ? Did ya swap #3 coil with another after CEL reset ? If everything seems the same, check all the vac hoses and electrical connections. Have ya done any recent work ?
Ya could also try some fuel system cleaner, maybe got some bad gas or an iffy injector. Perhaps try checking the fuel pressure ??? Personally, I don't think that the EGR valve is bad if the passageways were not totally clogged.
Ya could also try some fuel system cleaner, maybe got some bad gas or an iffy injector. Perhaps try checking the fuel pressure ??? Personally, I don't think that the EGR valve is bad if the passageways were not totally clogged.
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From: N35°03'16.75", W 080°51'0.9"
Had to go out of town for a few days, so dropped it off at the local shop. They did their diagnostic and say that the plugs and coils are good, but compression is inconsistent cyl-to-cyl (140, 120, 130, etc.).
They think the valves need adjusted and that it's related to the CEL/misfires. The car does (and has had for a few months) a pronounced 'tick' when running.
At 122k and .... 10+ years, I don't doubt the valve could use/need adjusting. I just don't know if that would account for misfires and the CEL.
They think the valves need adjusted and that it's related to the CEL/misfires. The car does (and has had for a few months) a pronounced 'tick' when running.
At 122k and .... 10+ years, I don't doubt the valve could use/need adjusting. I just don't know if that would account for misfires and the CEL.
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Good Luck, man.

