Q: my 1997 honda civic it has a swap with a d15b7 and it still has the vtec ecu and it idles at 1500 rpm under all condition and when

asked by on

my 1997 honda civic it has a swap with a d15b7 and it still has the vtec ecu and it idles at 1500 rpm under all condition and when i rev it, it drops down to normal then goes back up. even sometimes bounces from 2000rpm to 1700 rpm

My car has 244538 miles.
My car has a manual transmission.

The VTEC ECU (OBD-II) is not compatible with the D15B7 engine which is based on OBD-I standards. There is no way to flash re-program your existing ECU to fully "recognize" the older (D15B7) engine. Consequently, if you want to keep the engine, you would have to change out your ECU to the older one that came with the D15B7 engine. Prior to doing that, you could try to adjust the throttle plate and see if that brings the idle speed down. Another possibility is modifications to the idle air control valve and/or passageways. If you want a mechanic to take a look at what you have, and give you some advice, just request a high idle diagnostic and the mechanic will look at what you have and see if there are any other workarounds to resolve the high idle. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. my 1997 honda civic it has a swap with a d15b7 and it still has the vtec ecu and it idles at 1500 rpm under all condition and when

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car rumbles when accelerating for the first time after not using the car for 12 or more hours.

Hi there: What you're describing could be several issues ranging from clogged fuel injectors or dirty fuel filter to electronics related with a problem with the ignition coil or a sensor; even a vacuum leak. If you turn on the...

Q: Q: Brake lights do not work.

I don't have the wiring diagram for this vehicle handy, but one thing to check is the brake light switch. Hyundai actually issues a recall on these switches. I suggest you call the dealer with the VIN of your vehicle...

Q: battery very good but wont start.

When you are having the no crank condition, the system will need to have the starter tested to see if it is getting power from the ignition system to operate it. I have seen the starter not work and also...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.