Misfire on all 4 cylinders, exhaust out of manifold join
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Misfire on all 4 cylinders, exhaust out of manifold join
Misfire on all 4 cylinders, exhaust out of manifold join
Hi there… I could really use some help. My 2003 Civic EX broke down and long story short, I found the issue was the 12V power wire of an ignition coil was shorting to ground (sensor ground to be specific). So I fix that, replaced the ignition coil fuse and the car started right up. I was really happy to have my car fixed! Well… happiness quickly went away when I took it for a drive. Upon acceleration the car would severely hesitate and misfire and sounds like exhaust was coming from the front of the car. Check engine light came on and I got misfire codes for all 4 cylinders (P0300, P03001, P03002, P03003, P03004). There are no other error codes being generated. Troubleshooting things I’ve tried:
- With the car idling, I lifted each ignition coil one by one to see if any one coil didn’t have an effect on idling. They all did.
- I tried disconnecting the EGR valve to see if the car drove better. It didn’t. Disconnecting the EGR wiring harness had no effect at all.
- I tried disconnecting O2 sensor wire, but this had no effect on the car either (but did through the 02 sensor code).
- I tried disconnecting the cam shaft sensor (not crank shaft sensor) and this did make the idle a little worse. But had no effect on the misfire.
So here’s the interesting thing. There is exhaust coming from the spring loaded exhaust joint the connects exhaust manifold to the catalytic converter pipe. So I’m wondering if the catalytic converter went bad when I broke down and the back pressure is causing the misfire. Is there a way to test the catalytic converter without buying a new one? I live in California and they are pretty expensive to replace.
Any other ideas or thoughts? Any guidance will really be appreciated. thanks.
Hi there… I could really use some help. My 2003 Civic EX broke down and long story short, I found the issue was the 12V power wire of an ignition coil was shorting to ground (sensor ground to be specific). So I fix that, replaced the ignition coil fuse and the car started right up. I was really happy to have my car fixed! Well… happiness quickly went away when I took it for a drive. Upon acceleration the car would severely hesitate and misfire and sounds like exhaust was coming from the front of the car. Check engine light came on and I got misfire codes for all 4 cylinders (P0300, P03001, P03002, P03003, P03004). There are no other error codes being generated. Troubleshooting things I’ve tried:
- With the car idling, I lifted each ignition coil one by one to see if any one coil didn’t have an effect on idling. They all did.
- I tried disconnecting the EGR valve to see if the car drove better. It didn’t. Disconnecting the EGR wiring harness had no effect at all.
- I tried disconnecting O2 sensor wire, but this had no effect on the car either (but did through the 02 sensor code).
- I tried disconnecting the cam shaft sensor (not crank shaft sensor) and this did make the idle a little worse. But had no effect on the misfire.
So here’s the interesting thing. There is exhaust coming from the spring loaded exhaust joint the connects exhaust manifold to the catalytic converter pipe. So I’m wondering if the catalytic converter went bad when I broke down and the back pressure is causing the misfire. Is there a way to test the catalytic converter without buying a new one? I live in California and they are pretty expensive to replace.
Any other ideas or thoughts? Any guidance will really be appreciated. thanks.
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Joined: Jul 2012
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Re: Misfire on all 4 cylinders, exhaust out of manifold join
When I suspected my cat I took it to a muffler shop across the street sincce it was already off the car. He looked down into it to see if the inside was broken or plugged up. It wasn't so he said it was fine. Turns out it is fine. I would check that. I would sooner assume its related to that short than the cat suddenly going bad.
Recheck your work. Check the wire you fixed. Make sure everything you disconnected is properly connected.
Recheck your work. Check the wire you fixed. Make sure everything you disconnected is properly connected.
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WhitelightningEX
Honda Civic / Del Sol (1992 - 2000)
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Aug 9, 2006 07:37 PM