how much damage can i do to my car with misfiring cylinders 4 & 5
11-15-2007, 05:24 PM
#1
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how much damage can i do to my car with misfiring cylinders 4 & 5
codes are:
P0304 (misfiring cylinder 4)
P0305 (misfiring cylinder 5)
the car will coast fine, but shakes somewhat violently when it shifts gears
there does not seem too be any heavy fuel smell, and the exaust is whitish in color
P0304 (misfiring cylinder 4)
P0305 (misfiring cylinder 5)
the car will coast fine, but shakes somewhat violently when it shifts gears
there does not seem too be any heavy fuel smell, and the exaust is whitish in color
11-15-2007, 05:38 PM
#2
What do you want to hear?
I would drive it with the CEL on, but not flashing, but I also have 4 spare transmission. I had misfire on my car for almost 2 years. No vibration or shaking, just misfire codes here and there. A bottle of fuel injector cleaner fixed it, passed emission test and no CEL since.
11-15-2007, 05:55 PM
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Re: how much damage can i do to my car with misfiring cylinders 4 & 5
How is your coolant level? I would pull the plugs and look for intel (deposits, smell, color) as it would not cost you anything. If 4 and 5 are adjacent (I don't know) a not so good scenario is a blown HG between the two as indicated by low compression or high leakdown with a tester. You have to rule out ign and fuel, first, however. Do 4 and 5 share a "power stage"? Again, I don't know. A bad misfire (blinking MIL light) dumps unburned fuel into the cat, cooking it, and assuming the cyl is getting fuel and not misfiring for lack. Every year I resolve to build a venturi-type gasoline injector for my backpack blower but I never find the time.
11-15-2007, 06:10 PM
#4
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i'm going to put some fuel injector fluid into the tank in the morning
the CEL is solid... it did blink for a few seconds on start up but solid since.
it's the vibration that's bothersome
it's the vibration that's bothersome
11-16-2007, 06:02 AM
#5
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Re: how much damage can i do to my car with misfiring cylinders 4 & 5
Replace the plugs and move those two coil packs to other locations. If it goes away entirely..worn plugs..If it follows the moved coils...bad coils...If it stays put..something else...like a wet ECU or a headgasket.
A compression test would not be a bad idea.
A compression test would not be a bad idea.
11-16-2007, 12:08 PM
#6
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i put some fuel injector cleaner in this morning... but still shaking/vibrating at changes in speed
at idle the care seems to run fine, at constant hwy speed it runs fine.... but it shudders almost violently with changes in speed
11-17-2007, 09:33 AM
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The cleaner takes a while to work. Try two simple tests...
Does the engine rev and decel smoothly through the problem RPM range (ranges?)when not under load?
What happens when you apply the brakes hard and (drag racer style) rev the engine up through the problem range for just a second? Can you get it that high? TC slip will allow this for a second. That exercise will help isolate driveline effects from an engine management issue. If you do it with the hood up and the engine rotates you have a loose or broken motor mount. Those can produce judder, inherently, and by altering throttle input if the linkage is mechanical. It isn't on my 2000.
What happens when you apply the brakes hard and (drag racer style) rev the engine up through the problem range for just a second? Can you get it that high? TC slip will allow this for a second. That exercise will help isolate driveline effects from an engine management issue. If you do it with the hood up and the engine rotates you have a loose or broken motor mount. Those can produce judder, inherently, and by altering throttle input if the linkage is mechanical. It isn't on my 2000.
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11-18-2007, 08:54 AM
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the car will accelerate and cruise fine with little shudder.. BUT
but 3rd,4th or 5th gears seems to shake the car quite a bit.
i can rev the car in park and i hear like a whiny noise, the engine doesn't seem to shake
i can rev the car in park and i hear like a whiny noise, the engine doesn't seem to shake
11-19-2007, 01:34 AM
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Re: the car will accelerate and cruise fine with little shudder.. BUT
I have exactly same problem, but cylinders 1 & 5 misfiring. Have changed plugs, but not coils. But now I can´t do anything, since my battery is dead and trunk lock is broken. Can´t jumpstart since I can´t get to the battery!? :-( Any ideas? All help appreciated!