2003 Honda S2000 Engine Rebuild
Scotty, I bought the S2000 in Oct 2018 with 107,000 miles on it and put in additional 2000 miles since. I wasn't car savvy so I had paid a Honda dealer to do a pre-purchase inspection before I bought it from a private owner. I requested a scan on the car's computer (per your suggestion in one of your videos), but the dealer said they would only scan if there was a check engine light. So I trusted them and the car passed their inspection with flying colors. A BIG MISTAKE!
I use a pay-per-mile auto insurance which requires me to plug a device to the OBD port. It found cylinders 1 and 3 misfiring, and I started to notice rough idling. I bought it to a mechanic who also found misfiring codes on his expensive scanner. He test drove my car but the car was strong, and since there wasn't any check engine light, he thought the misfiring was within tolerance. He cleared the codes and they never came back.
But rough idling continued. I've checked spark plugs and coil packs, and cleaned the throttle body, MAP sensor and IACV. I bought it to a second mechanic and he said my IACV was bad. So I changed it and the car still idled poorly. Finally, this second mechanic did a compression test and found that cylinders 1 and 3 had low compression. He suggested to rebuild the engine or put in a "new" used engine.
I am pissed becoz I've relied on paid professionals but I got burned still. Now I have to make a decision and here are my questions.
I've been watching videos on low compression and I think the problem is the piston rings/cylinders, not head gasket or valves. I removed the engine oil cap and there was a breeze (not joking) gushing out and a loud humming noise from it. I think it is a bad blow-by, right?
Do you think pouring in a bottle of engine restorer for low compression will help? I doubt it will but still, no harm to ask.
I paid $11,000 for the car. The entire rebuild will cost $6-8k which is almost the same price as an engine replacement. But should I ask for a leak-down test to confirm the actual problem(s) and rebuild that part(s) only? Say piston rings/cylinders. Will it save me money? Or once the engine is removed form the car, it is better to redo the whole engine for good?
Besides the engine, another problem I have is there is oil dripping from wheel nuts and center caps on all four wheels. However, both the first and second mechanics couldn't find leakage from the brakes. And I don't experience any brake fading. What could it be?