1995 Honda Civic RPM

Tiny
BALTY
  • MEMBER
  • 1995 HONDA CIVIC
  • 4 CYL
  • FWD
  • MANUAL
  • 90,000 MILES
So my rpm gauge is declining when im at a stop: I start the car and thr rpm is at 2 but later on it goes down to 1 or a little below and its not performing lik before. Im thinking I might need a tune-up, what is your opinion?
Do you
have the same problem?
Yes
No
Friday, September 24th, 2010 AT 3:57 PM

5 Replies

Tiny
DRCRANKNWRENCH
  • EXPERT
By 2, I am assuming you mean 2000 RPM. This is high for the Civic as it should be around 800 RPM give or take a little. How long has it ran at 2000 RPMs at idle?
This is symptamatic of a vaccum leak.
There is a vaccum routing diagram under the hood of your car. This is not all of the places where it could be lleaking, but it is a good start. Other places that can leak are cruise controls, throttle body gasket and PCV valve. With the motor running you can hear a vaccum leak sometimes or you can put your hand over the throttle body and if it keeps running, it is a vac leak. From there a vacuum gauge is the best way to track down a vac leak.

Try that first and then by process of elimination, try the following;

A good place to start tracking down the problem would be to get some BG44K, if your local auto store does not have it you might have to go to a service station, and run it in a tank full of gas. If it improves from the BG44K, then run another can of it. The second can is just to remove heavy deposits if you don't normaly run an injector cleaner.

A standard tune up should at least include the following;
Replace the plugs, plug wires if they look like they need it, cap and rotor.
A can of injector cleaner.
Engine oil and filter using an OEM filter. I recomend OEM because it has an anti-drainback valve. Wait to replace the engine oil and filter until you have finished the tank of gas with the BG44K in it. It will clean up the intake and combustion chambers as well as valves, etc, so well that the oil will get dirty from the released deposits.

If this does not solve the problem, then you can start looking at the sensors.
I would first test the Throttle Position Sensor, (TPS), then Idle Air Control Valve, (IAC). Working by process of elimination is the only way to work through an electrical issue.
You need a mulitimeter and specs to perform these tests. I can find the specs online or you can get a Haynes manual which is handy as it will walk you through the steps and is a lot cheaper than the factory service manual. Although it is not as thourogh as the factory manual.

Good luck and let me know how it goes.
Was this
answer
helpful?
Yes
No
Friday, September 24th, 2010 AT 7:00 PM
Tiny
BALTY
  • MEMBER
I don't knw Wat the rpm measure is. Im talking about the needle on the dash board
Was this
answer
helpful?
Yes
No
Friday, September 24th, 2010 AT 11:44 PM
Tiny
DRCRANKNWRENCH
  • EXPERT
You are correct, they are the same thing just different terminology.
The 2 main gauges on the dash are the tachometer and the speedometer. The tachometer measures RPMs by pointing the needle to the number on the gauge. The numbers are the Revolutions Per Minute, (RPM) of the engine. If you look at the gauge there is a, "x1000" which means that when the needle points to 2, the engine is spinning at 2000 revolutions per minute.
Is your first instict that your car has just started doing this?
Was this
answer
helpful?
Yes
No
Saturday, September 25th, 2010 AT 2:36 AM
Tiny
BALTY
  • MEMBER
Yes it is. It's not performing how it used to.
Was this
answer
helpful?
Yes
No
Saturday, September 25th, 2010 AT 10:42 AM
Tiny
DRCRANKNWRENCH
  • EXPERT
Ok.
Then it does sound like a vacuum line has started leaking, the Idle Air Control Valve, (IACV), Fast Idle, (Idle Air and Fast Idle act as choke circuits to keep idle at 800 RPMs when the motor is cold or when the load on the motor, like air conditioning or other accesories change. Least likely is a gasket in the intake tract like Throttle Body and Intake Manifold Gaskets.

From previous e-mail, refer to it and the, "Things to Check First", section on this site is very good to diagnose the problem.

Also, don't look at the entire e-mail from before as it is more than needed right now. Just use this part;

This is symptamatic of a vaccum leak.
There is a vaccum routing diagram under the hood of your car. This is not all of the places where it could be lleaking, but it is a good start. Other places that can leak are cruise controls, throttle body gasket and PCV valve. With the motor running you can hear a vaccum leak sometimes or you can put your hand over the throttle body and if it keeps running, it is a vac leak. From there a vacuum gauge is the best way to track down a vac leak.

Let me know how it goes.
Was this
answer
helpful?
Yes
No
Saturday, September 25th, 2010 AT 6:15 PM

Please login or register to post a reply.

Recommended Guides