Need help with my ford taurus, plugged cat?
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Need help with my ford taurus, plugged cat? Hey I need some suggestions before I decide to start tearing **** up. I have an 02 ford taurus and lately it has been having a very rough idle and now it has started to misfire, flashing light and all. It does it at idle and right as I come off idle buy goes away once the rpm's go up a little. I recently replaced the entire EGR system, plugs, wires, fuel filter, air filter, and i cleaned the MAF.
I am now thinking it is a plugged catalytic converter. Does this sound reasonable for what i am experiencing? This is pissing me off and I need to fix it because its driving me nuts.
I am now thinking it is a plugged catalytic converter. Does this sound reasonable for what i am experiencing? This is pissing me off and I need to fix it because its driving me nuts.
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Originally Posted by 01WS6/tamu
could be a coilpack. I have had a lot of those go bad on the taurus' through the shop. If it's been missing long enough it could have killed the converter.
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Originally Posted by 01WS6/tamu
Depends, DIS does weird **** when they start acting up it's like trying to diagnose a woman sometimes.
had a pretty similar situation to another car i had, it turned out to be a coil pack, if you can get to the wires easy, what i did was hook a timing light up to all the different wires and could easily tell which one wasnt firing correctly
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Originally Posted by thunderstruck
had a pretty similar situation to another car i had, it turned out to be a coil pack, if you can get to the wires easy, what i did was hook a timing light up to all the different wires and could easily tell which one wasnt firing correctly
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Unplugging the injectors helps you determine a power balance problem, not necessarily an injector problem. Sounds like cylinders 3 and 4 are misfiring. And over the last 10 years of working on Fords exclusively, I've replaced maybe 2 injectors. Fords injectors just don't go bad.
And you never stated what engine you have... 12v or 24v?
What plugs and wires did you use when you did the tune up?
And when you replaced the entire EGR system (why?), did you also update the DPFE?
From all the symptoms you're describing, especially the misfire diminishing when not at idle, suggests burned/leaking exhaust valves, which are quite common.
And you never stated what engine you have... 12v or 24v?
What plugs and wires did you use when you did the tune up?
And when you replaced the entire EGR system (why?), did you also update the DPFE?
From all the symptoms you're describing, especially the misfire diminishing when not at idle, suggests burned/leaking exhaust valves, which are quite common.
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Originally Posted by Marc 85Z28
Unplugging the injectors helps you determine a power balance problem, not necessarily an injector problem. Sounds like cylinders 3 and 4 are misfiring. And over the last 10 years of working on Fords exclusively, I've replaced maybe 2 injectors. Fords injectors just don't go bad.
And you never stated what engine you have... 12v or 24v?
What plugs and wires did you use when you did the tune up?
And when you replaced the entire EGR system (why?), did you also update the DPFE?
From all the symptoms you're describing, especially the misfire diminishing when not at idle, suggests burned/leaking exhaust valves, which are quite common.
And you never stated what engine you have... 12v or 24v?
What plugs and wires did you use when you did the tune up?
And when you replaced the entire EGR system (why?), did you also update the DPFE?
From all the symptoms you're describing, especially the misfire diminishing when not at idle, suggests burned/leaking exhaust valves, which are quite common.
I replaced the EGR because the EGR vacuum regulator broke so I replaced all EGR components at the same time. I replaced the regulator, EGR valve, and the DPFE. The EGR system is working fine now.
Maybe ill borrow a leak down tester and check it out.
Originally Posted by brad8266
Bosch platinum plugs,
THROW THOSE AWAY IMMEDIATELY! 
Those plugs are junk, and are the root source of so many misfire problems that you just can't imagine... google it. I encounter these pieces of trash on at least a weekly basis with all sorts of misfire and CEL issues - and the customer often argues with me because he just paid $10/each for "the best plug money can buy" - yet all the concerns started immediately after the plugs were installed. If the misfire continues after the proper plugs are put in (Motorcraft platinum are cheaper and work better), then post again.
Edit: A plugged converter will not affect idle at all 99 times out of 100. The most common symptom is the inability to rev the engine past 2500-3000RPM, and a severe lack of power. When you replace those junk plugs (YOU WILL REPLACE THOSE!), disconnect the battery while working on the car for safety first of all, and to reset both any DTCs stored and the adaptive fuel trims.
Last edited by Marc 85Z28; Mar 9, 2007 at 05:56 PM.
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Originally Posted by Marc 85Z28
THROW THOSE AWAY IMMEDIATELY! Those plugs are junk, and are the root source of so many misfire problems that you just can't imagine... google it. I encounter these pieces of trash on at least a weekly basis with all sorts of misfire and CEL issues - and the customer often argues with me because he just paid $10/each for "the best plug money can buy" - yet all the concerns started immediately after the plugs were installed. If the misfire continues after the proper plugs are put in (Motorcraft platinum are cheaper and work better), then post again.
Edit: A plugged converter will not affect idle at all 99 times out of 100. The most common symptom is the inability to rev the engine past 2500-3000RPM, and a severe lack of power. When you replace those junk plugs (YOU WILL REPLACE THOSE!), disconnect the battery while working on the car for safety first of all, and to reset both any DTCs stored and the adaptive fuel trims.
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I replaced the plugs with champion coppers and the problem seems to have cleard up a little bit, but it is still there, just not as much. It only misfires and runs a bit rough when i idle. Almost everytime I touch the gas the roughness stops instantly.
Originally Posted by brad8266
I replaced the plugs with champion coppers and the problem seems to have cleard up a little bit, but it is still there, just not as much. It only misfires and runs a bit rough when i idle. Almost everytime I touch the gas the roughness stops instantly.
You went from the worst plug that you could put in that engine, to the second worst. Champions are crap too, just less expensive. They only work in late model Mopars. Again, and finally, PUT IN MOTORCRAFT 
Autolites will work too, but they a far from optimal. Ford has redesigned their platinum plug line 4-5 times in the last few years. Autolite still uses the original design.
And while you're at it, ohm out those AutoZone wires during a wiggle test with the wires hot...
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Originally Posted by Marc 85Z28
You went from the worst plug that you could put in that engine, to the second worst. Champions are crap too, just less expensive. They only work in late model Mopars. Again, and finally, PUT IN MOTORCRAFT Autolites will work too, but they a far from optimal. Ford has redesigned their platinum plug line 4-5 times in the last few years. Autolite still uses the original design.
And while you're at it, ohm out those AutoZone wires during a wiggle test with the wires hot...
I guess I 
myself. Ill wait till monday to go get some motorcraft plugs, lol.
Originally Posted by Marc 85Z28
From all the symptoms you're describing, especially the misfire diminishing when not at idle, suggests burned/leaking exhaust valves, which are quite common.
). The cooling systems on the engines are crap, and often clog much of the system, including the cylinder head ports which overheat the exhaust valves.How did the wires check?
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Originally Posted by Marc 85Z28
Time for a compression test. These engines have unusually high cranking compression - often over 200psi. A cylinder with anything lower than the rest is likely a burned exhaust valve, ESPECIALLY if you've ever had your coolant turn to coffee (dark brown and smells nasty ). The cooling systems on the engines are crap, and often clog much of the system, including the cylinder head ports which overheat the exhaust valves.
How did the wires check?
). The cooling systems on the engines are crap, and often clog much of the system, including the cylinder head ports which overheat the exhaust valves.How did the wires check?
