Southernjarhead

I just bought a 2001 Honda Civic Ex with a manual transmission, the guy told me from the get go that the IAC Valve and the Thermostat were bad which is no biggy. I had to order the IAC which ill be getting and installing later today but i decided to hit it with some good carb clean to try to get it going, also i replaced the thermostat and when i pulled the old one out the only piece left of it was the top little dome piece, no spring no plunger or anything else, so that kind of worries me. When i get going down the road it runs fine but wont go past 2500 rpm at all. even with cleaning the IAC, it does have codes but i dont know what they are yet as i cant get the car to the auto store to have them read. Anyone have any suggestions and has anyone ever heard of a thermostat just breaking apart like that?

JRCivic1

It is unlikely that the thermostat just fell apart and the parts are traveling throughout your engine's cooling system passages. My bet is a previous owner has experienced some overheating and attempted to "gut" the thermostat to cure the overheating... which really won't happen. If you put a genuine Honda thermostat back in and you have overheating issues, you will need to address the real cause and fix it. There is a good chance that your lack of power has nothing to do with the IACV and thermostat, but in fact, it is either a clogged cat/exhaust system or the engine has out of mechanical timing. Also, since you haven't checked your engine codes... there is a chance that you either have a crank or cam position sensor failure. This type of failure will cause the vehicle to experience a rhythmic rev-limit type of action somewhere between 2500 and 4000 rpm... not like a "loss of power" even though the engine sounds normal.

Southernjarhead

I was able to get a code reader from a friend and you were right the Cam position sensor and the ELD were both bad i replaced them this morning and cleared the codes and im driving just fine now, the car is only overheating at a full stop so i believe it may be the fans or i just need to finish filling it up with coolant as i already replaced the thermostat. Thank you for your knowledge.

JRCivic1

You are most welcome.