My car is a 1998 Honda Civic DX hatchback 5 speed manual. About 180,000+ miles. For a while now the car seems to have a problem with power under load. If I am on an incline the engine will start making a metallic gurgling noise as I push on the gas. It increases as I give it more gas, or the hill gets steeper; at which point the car usually begins to slow down depending on my speed. It is most noticeable when I shift into a higher gear and then my speed drops into the range where I could downshift. It also happens often however at 60 mph+. On inclines at that speed, the car will gradually lose speed down into the 50’s if the hill is long enough/steep enough even with the gas pedal floored. I’ll need to shift into fourth to keep at 50 mph until I’m over the hill.
I’ve been told by a few friends/mechanics that it may be the catalytic convertor. Hard to test it or just weld on a new one though since the cat is integrated into the manifold, etc. So I took it to a trusted mechanic who did a bunch of work. He said it was only firing on three cylinders instead of four due to carbon tracking, but wasn’t concerned with the cat. He did a tune-up and replaced the distributor cap and rotor, spark plugs and wires, valve cover and gasket (leaking), air filter and fuel filter, and cleaned the throttle body. Also replaced both rear strut assemblies. Totaled nearly $800 including a couple other minor fixes.
Until now there had been NO check engine light signaling a problem. I got the car back and it felt good at first, but still seemed to make the noise albeit quieter. The power was better, but only for maybe a couple days. The engine again started making the noise more often and losing power in the same ways. Also, the check engine light came on a few days later. Blinking the first time, then it would come on for a couple of days, then off for a couple, etc. Now it has come on and stayed on constantly for a couple of weeks. I had the engine codes read and got three codes:
P1456- the usual emission control system leak… fuel cap possibility, etc. I’m guessing it isn’t this for the most part…
P0141- "secondary HO2s12 (Heated oxygen sensor- bank 1, sensor 2) circuit heater malfunction… hmmm…
and the strangest of all since I’d expect it to be fixed…
P0301- “cylinder number 1 misfire detected” ugh…
So it could be something else with the cylinders going on, O2 sensor having to do with cat. stuff, etc.? Any idea what I’m looking at here?
I also will be due for a timing belt change soon I believe, but that would not be causing any of this I don’t think. I’ll be bringing it back to the mechanic to have a look again, but haven’t had the time yet. He knows about it though and is expecting me to bring the car in. It’s just a frustrating problem. I would like to fix it so that I can have a little bit of pick-up sometimes! Thanks for any help!