wfd2

I bought a 2011 Civic LX back in May and for the past month or so the idle goes up to ~1200 RPMs when I turn the steering wheel. This happens when I'm trying to park the car in a parking space and causes the car to jerk forward. It also happens if the car is sitting still and in park.

The dealership just called and said it was "normal". I know the power steering pump puts a little extra strain on the engine, but to rev up as high as 1500 RPMS when I'm turning the steering wheel isn't "normal". They say that it's the way the transmission downshifts that causes the problem. They couldn't explain why it does it in Park too.

My mom has a 2003 that doesn't do this. I owned a 99 that didn't do this. If you aren't paying attention, that little extra boost forward into a parking space can catch you off guard.

Does anyone else have this problem or is it a "feature" of this year Civic? You'll know quick if you are experiencing the problem-- let the car heat up to operating temp and then just turn the wheel while sitting still. The RPMs will go up to 1200-1500 if you do.

I appreciate your feedback and time. I just don't think that Honda would program the vehicle to overcompensate the idle like this, especially at low speeds like pulling into a parking lot.

Thanks in advance,
Bill

ezone

There is a P/S pressure switch input to the PCM.

The P/S switch just tells the PCM to expect some sudden additional load, and the PCM raises the engine RPM accordingly. If it didn't have this feature, the engine would fall on its face when you crank the steering wheel, before the idle speed control program could catch up.

It raises the engine RPM in anticipation of a load by (I'm guessing) approx. 100-300 RPM on a hot engine when the P/S pressure switch is activated, to compensate for the (amount of possible) additional load caused by the P/S hydraulic pump. (At full pressure assist, the pump requires more engine power than it would need at a low amount of assist. Road speed vs. tire resistance vs. steering wheel effort. It varies.)

However, it uses only an ON/OFF switch that is pressure activated, so it can't really have a variable RPM change that is load dependent, and the programming in the PCM still has a target idle RPM that it tries to hit.




If the engine is not yet at operating temperature, the target idle speed is higher, and the RPM boost from the P/S input may be higher than it is on a hot engine.

Example (random):
185 degrees F engine speed target~800rpm
25 degrees F engine speed target~1400rpm
Add rpm for loads~???rpm per load

Idle speed targets can change with vehicle speed too, and probably several other factors.

Air conditioner ON/OFF has similar programming in the PCM for a boost in idle for the expected load, but the load of the AC compressor at idle is relatively constant, not variable. If the compressor clutch was disconnected but the system is switched on, you can hear the idle speed raise for a second before the idle speed program takes over and lowers it to its target RPM.

Same deal as above for when you drop the shifter into gear on an automatic trans.


If I had a similar car here at the moment, I could check what it does, but that isn't happening right now.


It's probably normal. Keep your foot ready over the brake pedal when going slow in parking lots.

ezone

Oh yeah, the car has throttle-by-wire, your foot pedal is only an input to the computer. The other cars you mentioned use a cable to physically control the throttle via your foot. Not sure if that makes any difference.

wfd2

ezone,

Thanks so much for your help. After your explaination, it makes sense. However, it seems as if my Civic is over compensating for the P/S. Do you think a warm engine should peak at 1200 rpms even at rest in park? (I've seen as high as 1500 rpm) What I forgot to post in my opening question, the RPMs will also "hang" sometimes, not going down for 3-8 secs after I release the wheel.

I appreciate you sharing your experience and knowledge!

Bill

ezone

Like I said, I don't have a similar car in the shop at the moment to check.

12-1500rpm might be possible if the switch were engaged but no/low load were present. Maybe higher with a cold engine.
I'm not sure about the reaction time of the idle program either, nor how much authority it would have over the PS input. If I had a similar car at the moment, I could try a couple things, but I don't right now.

3-8 seconds hang time is too long IMO, if it is caused by the PS input. It should react immediately. Maybe the switch is sticking once in a while. You could disconnect the switch and try it to see how that affects it. The switch is attached to the high pressure hose between the pump and the steering rack, and you probably have to get under the car to reach it, or possibly reach it through the passengers wheelwell.

The easy way would be using a high end scanner (dealers HDS scanner) to read live engine data.

Wait up here....
That sucker should be under warranty. Don't touch it.
Make the dealer deal with it....
......But someone has to prove it is a problem first. (We deal with crack smokin' whiners every day, so expect skepticism about your complaint.)
Quickest way is to compare it to another similar car. Test drive one off of the dealers lot and take notes. If a similar car is drastically different from yours, that is usually proof enough for me. You would have to show the tech what you found, test drive both cars with him or a service manager or something.

If your car is VERIFIED as having a problem and the dealer still won't do anything at that point, call the 1-800 customer assistance number in your owners books. (The dealer will probably hate you after that.)
Late '09, '10-'11 are all basically the same, but the closer year you can get to yours is better to compare with.

HTH

Gunner

I was gonna say just take it to the dealer..i know its a pain but thats what the warranty is for.. I know my 07 idles around 600 and jumps to around 1k for the P/S..I can check later it might be more or less..

wfd2

Case closed I guess.

I took it back to the dealer where my salesman offered to take me for a test drive in a 2010 they had on the lot. (My dealership is really customer-oriented and they had no problem helping! Whew...) After driving it until it warmed up, I turned the wheel and it performed the same as mine. It looks to be normal operation, as eZone originally stated.

I appreciate you sharing your expertise with me eZone. You were right on the money.

Happy New Year to all!

Bill

Gunner

Glad to hear you were helped. Happy New Year to you as well..

ezone

Good to hear it, thanks for the feedback.