97 Accord LX
On city streets, at constant pedal pressure, the RPMS will stay steady, and then every once in a while, the RPMs drop for a second (approx 500 rpms drop), and then it goes back up to where it should be.

Also, I can feel a slight loss in power when this happens, then it goes back to normal.

During a 10-second interval, this "dropping" will happen 2x

On freeway, car drives normally

Any ideas?

So far I changed plugs, air filter, pcv valve.

 

I have a pretty similar experience. Do you notice this drop more frequently at night, with the headlights on, stereo and AC? Does the headlight, or dashboard light dim, or loose brighness? I think my problem is due to a bad alternator, and it might be the same case for you.

 

I have the same problem here and I drive a 98 lx. It just started to happen to me and im trying to figure out why. Anyone got explanations? Mine drops down to zero then shoots back up to normal and my cd powers off then back on. Its like a power surge or something.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legendaryyaj &raquo;</TD></TR><TR><TD CLASS="quote">I have the same problem here and I drive a 98 lx. It just started to happen to me and im trying to figure out why. Anyone got explanations? Mine drops down to zero then shoots back up to normal and my cd powers off then back on. Its like a power surge or something.</TD></TR></TABLE>

I would take the car to Autozone and get a free alternator check. I would assume that the car would stall once it drops down to 0 rpm, but if it stays alive

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by -Bionic- &raquo;</TD></TR><TR><TD CLASS="quote">Do you notice this drop more frequently at night, with the headlights on, stereo and AC? Does the headlight, or dashboard light dim, or loose brighness? I think my problem is due to a bad alternator, and it might be the same case for you.</TD></TR></TABLE>

Thanks for the replies.
No , it also happens during the day without lights on, or a/c on

 

How many miles do you have? Is it a 4-cyl? Sounds like a possible bad alternator, but depends on mileage usually.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Elvis1977 &raquo;</TD></TR><TR><TD CLASS="quote">How many miles do you have? Is it a 4-cyl? Sounds like a possible bad alternator, but depends on mileage usually.</TD></TR></TABLE>
I got a 4 cyl with 141k. I guess it might be the alternator then.

 

Yeah with that many miles...the alternator could be the problem. However, to be safe go to Autozone and get a free alternator check.

 

Yeh, I agree replace the alternator after checking it with autozone. You really put alot of miles on you car fast. I also have a 4 cyl. 98 accord lx with 116k and i thought i had alot of miles. Also, Iam willing to bet 100 dollars that your front motor mount is cracked. Does your car slightly vibrate at idle? I had to replace mine at 115k. It's hard to see any cracks while on the motor, but when you remove it you will see cracks for sure. It's very easy to replace, and easy to get to. Also, it costs only 38 dollars from the dealership. Replace it youself if you have vibration at IDLE.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Elvis1977 &raquo;</TD></TR><TR><TD CLASS="quote">Yeh, I agree replace the alternator after checking it with autozone. You really put alot of miles on you car fast. I also have a 4 cyl. 98 accord lx with 116k and i thought i had alot of miles. Also, Iam willing to bet 100 dollars that your front motor mount is cracked. Does your car slightly vibrate at idle? I had to replace mine at 115k. It's hard to see any cracks while on the motor, but when you remove it you will see cracks for sure. It's very easy to replace, and easy to get to. Also, it costs only 38 dollars from the dealership. Replace it youself if you have vibration at IDLE.</TD></TR></TABLE>

HAHA yea i know i got a **** load of miles...i got it 1 year ago with 126k and it now has 141K. I drive around a lot, you know how kids are, always eager to go everywhere. Well my car doesnt vibrate at idle, it acutally sits very still. So um..wheres my $100. LOL. Is there anythign to compress or hard to to when replacing the mount. I have no air tools so i dont like doing hard stuff that involves compressing or things that need air tools. i.e. dropping car. I know u can do manually but im impatient.

 

If you put the transmission in gear, and foot on the brake let the car idle. Then, turn your headlights on. Then turn your rear defroster on. Then turn your A/C on. Now, do you feel vibration at idle? If so, then a motor mount is to blame. Usually the front one especially with alot of miles. I forgot to ask you if you have an automatic or 4-speed. If you have a 4-speed, then vibration is usually not as bad as an automatic. To replace it just lift the motor SLIGHYLY with a floor jack and remove the mount. Put in the new mount. LOWER the engine and tighten all bolts.

 

I think you mean 5-speed, the autos have 4.

 

Did you replace the mount with another stock mount? Or did you get one with stiffer bushings?

 

I had a similar problem with my old prelude. At idle the rpms would drop once every 20 seconds or so. It turned out one of the spark plug wires had a knick and the exposed wire was shorting out against the hood.

 

Update:
It was the plug wires. (this was actually my co-worker's car, not mine)

He was using Nology "Hotwires". Once he replaced them with stock Honda plugwires, the problem went away.

Thanks for the feedback, guys

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TAG &raquo;</TD></TR><TR><TD CLASS="quote">Update:
It was the plug wires. (this was actually my co-worker's car, not mine)

He was using Nology "Hotwires". Once he replaced them with stock Honda plugwires, the problem went away.

Thanks for the feedback, guys</TD></TR></TABLE>

What was wrong with the Hotwires?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Legendaryyaj &raquo;</TD></TR><TR><TD CLASS="quote">What was wrong with the Hotwires?</TD></TR></TABLE>

We don't know. Maybe they went bad? (please don't ask me why)

Basically, after replacing them with stock wires, the problem disappeared.
HTH

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TAG &raquo;</TD></TR><TR><TD CLASS="quote">

We don't know. Maybe they went bad? (please don't ask me why)

Basically, after replacing them with stock wires, the problem disappeared.
HTH</TD></TR></TABLE>

why? j/k man haha how's your car running?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by accordfreak &raquo;</TD></TR><TR><TD CLASS="quote">why? j/k man haha how's your car running?</TD></TR></TABLE>

Aw man, you had me there for a second

The CRX is running pretty well. I think I need to do some low-rpm tweaking on my tune however. It dies at startup on cold mornings, not sure exactly why. But it was not doing this before the tuning.
Otherwise, it's a blast to drive. I just need to drive it more in the hills, and less on the freeways (tickets)

How about that sweet Accord of yours? How's she doing?

 

about the motor mounts, i think the rear motor mounts (on AUTOs) absorb more of the vibration than the front one. if its vibrations and motor mounts, i think the rear motor mount would be the culprit