Starts and runs fine until engine is warm
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Starts and runs fine until engine is warm
2001 Civic HX manual with 167k miles. It starts and runs. Have gone to 3000 rpms after starting no problem... until it reaches operating temperature. Then it runs very rough anything over 1500 rpms. Disconnected the IACV and it got worse. It did not go back to 700 rpms after warm up but stayed at 1100 rpms. There is no CEL. Instead of going down a series of rabbit holes I am hoping to learn from your knowledge and experience.
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Thanks.
That helped somewhat. After warming up to operating temperature the engine could go to 2000 rpms with occasional misses. The misses increased as rpms increased.
That helped somewhat. After warming up to operating temperature the engine could go to 2000 rpms with occasional misses. The misses increased as rpms increased.
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Sounds serious. Any remedy for that?
Maybe some background would be helpful. During the cough-cough (2020 to 2022) and to the present we did not need or use this car. We have two other vehicles and didn't even use those very much during that period. The HX was not in a garage and so exposed to the elements. I added probably three bottles of Heet in the fuel over time, thinking there was water in the fuel. Did not do any good.
Maybe some background would be helpful. During the cough-cough (2020 to 2022) and to the present we did not need or use this car. We have two other vehicles and didn't even use those very much during that period. The HX was not in a garage and so exposed to the elements. I added probably three bottles of Heet in the fuel over time, thinking there was water in the fuel. Did not do any good.
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Re: Starts and runs fine until engine is warm
just pull it out and peek inside...
see samples below
https://www.google.com/search?sca_es...h=684&dpr=1.25
see samples below
https://www.google.com/search?sca_es...h=684&dpr=1.25
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Pulled the exhaust-cat assembly off and checked inside. This is the first cat that I have seen. It appeared like what I imagine a new cat would look like. No clogging at all.
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Not to be that guy but I'm assuming you threw a code reader on it despite the CEL not coming on? Stored codes could be just as important.
My first guess is probably a fueling issue only because that's all that really changes between cold and warm. It'll run super inefficiently when cold, and maybe it stays that way when it warms up.
If that's not it, throw a compression tester on it.
My first guess is probably a fueling issue only because that's all that really changes between cold and warm. It'll run super inefficiently when cold, and maybe it stays that way when it warms up.
If that's not it, throw a compression tester on it.
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