Hi everyone. Sorry if my questions look stupid ( A Newbie Civic Onwer here)

I just own a So4 (EJ6) with B20B B16Head (Now with auto Gearbox Duhhhh...) <===== Going to manual at the future
Its a fun and powerfully little car to drives ... gonna love when the V-tec Kickin yo.. hhaha.. well let goes back to my questions ..

i have a problem As the title said . When i Turn on the aircorn the Rpm will goes up and down. especially when you put the gear to P or N. it will goes away sometimes when in D.. and sometimes it will goes away if i turn on the AC.
what shall i check ? the throttle body ? some people say its may cause by (air-corn Choke) .
would like to heard advices from expert here :D

Thanks
Any reply in this would be highly appreciated

Tq

 

You bought an already swapped car-- in many cases the previous owner didn't build it out properly and doesn't know how to fix it. Eventually he gets frustrated and puts it up for sale.

Also the A/C will overload and bog the engine if the condenser fan doesn't work. So check that first.

 

The condenser fan will work when the engine are hot.. It turn on automatically.. My aircorn are very very cold..

I will get back. To the pervious owner soon. But before that i would like to troubleshoot 1st. 🙂

 

check engine light? what ecu?

 

No engine light..
P28 now.

(previously stock ecu also have same symptoms)

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Does the check engine light works?

 

Yes. it run fine no other problem... only the RPM high and low thingy ( more noticeable when AC on with N or P) it just goes away when driving.. (D or D1, D2 ,D3 or D4)
thinking buying a OBD tools for check...

 

When asked if check engine light works, are you confirming the light comes on for 2 seconds and turns off when you go to start the car?

You have seen the check engine light come on for a moment before starting the car? Or you never see the check engine light come on, ever?

 

Will double comfirm tomorrow.. I think there is a high changes that check engine light is nt working.

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To be clear, turn the key from off to the on position, but not all the way to make the engine start. The CEL should come on for a bulb test and then go out after 2 seconds.

OBDII scanners do not work with a P28 or other OBD1 ECU.

 

Here... The engine light is working..



Yes . The engine light is working.

 

Thanks for the advices.. Anyway here is the engine light. Is cel will comeout and go out after two second..

The cel is working too.