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Hi folks,

This is my first posting to this forum. I found this website fr google.

I'm not in the US, but I have a 7th Gen 2004 version of Civic 1.7L D17A2 engine, hence I thought u guys may be able to help me out. Here's my problem:

At times, my engine's rpm will drop till ~300 when the car idles at the traffic lights with aircond turned on. The engine shudders and after a while, it goes back up to the normal 750rpm. This happens only in the day time. I've not have any occurence at the night time before. The frequency of it happening is like twice in 3 days time.

I've sent it to Honda service center. They adjusted the teppet and replaced spark plugs inc. coils. However, the problem is still there. As a result of the teppet adjustment, the engine does not shudders that much now, but the rpm still drops. The problem is still there.

I'm not sure if this could be valid, but I have a hypothesis that if I turn on the lights, this problem will occur. Twice in the morning, I purposely turn on the lights. No rpm drop at all.

Appreciate any advice from you folks here. Thanks in advance.

 
Rep Power: 812

I don't know what a teppet is, but check the idle adjust sticky in this forum. That should fix it. You only need to raise it a little to keep from stalling out. Could also be a bad sensor, since the idle is mostly computer controled.

 
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hi gearbox,

i was told by the mechanic that there's no way we can adjust the idle rpm manually. it's supposed to be fully controlled by the ecu. i agree with ur suggestion that there could be a problem with the sensor, but which sensor should i get the mechanic to check first? he did a computer check on the IACV (idle valve) and air flow sensor and they all checked out fine. the hard part about troubleshooting this problem is that it only occurs intermittently.

back to my problem, i notice the rpm drop to ~300rpm but it does recover after that. do you think this is acceptable? or is it really a problem in my car? my civic is just 2 months old.

 
Rep Power: 812

The idle at neutral with no load should be around 700rpms and maybe drop to 600 while in gear. Read my post about adjusting idle. Yes it can be done. There is a set screw you adjust to open/close the throttle plate, which will raise/lower the idle. Read the sticky.

 
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I think the proper way to get to WOT, is to take the black piece out from under the pedal, and not tighten the cable. This does not apply to him, since he needs to raise his idle, so the other thread would work. You can press the gas pedal down 2-3 inches further, with no prob at all. I did this 80,000 miles ago. That is a useful thread, I just dont feel that is the proper way to get to WOT safely without overtightening/snapping cables. I can slam my gas down, and know I am reaching WOT without worrying I would snap anything from tightening it. Just my opinion.

 
Rep Power: 812

You should be reaching wot without taking the black piece out. I checked my monitor, and it says 99-100% throttle when the pedal is pressed down as far as it goes. And my throttle cable has the recommended 0.5 inches slack.