2002 honda civic si 1.7L I4 manual, with 343,000km, nearly everything is oem. Problem occurs when driving, the car will bog down and the revs will drop to zero, even with gas pedal pressed fully to the floor nothing happens. When the gas pedal is fully released and then pressed again the revs on the tachometer come back and the car is able to accelerate. This occurs approximately every 30 seconds to 1 minute, the car idles fine and starts up with no problems at all.
I have scanned the car and get the following codes; P0112 and P0113 (intake air temperature sensor 1 circuit low bank and high bank, respectively), P0325 (knock/combustion vibration sensor 'A' circuit). I have tested the IAT sensor with a multitool and based on Honda specs for resistance at various temperatures it seems to be working properly. I have also tested the knock sensor as best I can with a multitool and it seems to be working fine as well. I also get code P1457 (Evaporative emissions control system leakage) but i don't think this would be related to the problem?
I have also tested the TPS and MAPS sensor with the multitool and those seem to be working properly based on voltage and resistance values during testing. I don't think it is the distributor cap and rotor as the car starts up and idles fine or a fuel pump/filter problem for the same reasons. The throttle cables seem to be in good condition as well.
Based on some research it may be the computer that needs to be replaced but i am unsure. Any insights are greatly appreciated.
Start with basics. The car is 20 years old. How old are the spark plugs, air filter, fuel filter, and fuel pump? Are you getting sufficient fuel pressure at the fuel injector rail? Is your catalytic converter clogged?
The EVAP code indicating a leak could be messing up fuel delivery and causing the problem, along with the malfunctioning air intake temperature sensor that is input info to the computer that affects the air/fuel mixture. I would start by checking the gas cap and EVAP control valve solenoid and absolutely replace the air intake temp sensor with the OEM part.
