92 Accord idle problem!!!

[J00ky]

Hi this is my first thread in the forums! I got a 92 Accord EX (all stock). When its cold (-5 celcius or lower), after turning the car on for a fiew minutes, the engine will start to idle at higher rpm (1600 if mildly cold, higher as it gets colder) then, just when its starting to warm up and the rpm decreasing, it suddenly drops to 1000 rpm, then revs back to 1500-1600 rpm, and drops again to 1000... as if someone is pressing slowly on the throttle for 2 seconds then letting it go. However, this lasts for a fiew minutes (the colder it is, longer it lasts), then it just dissapears and the engine idles rock stable. When i go on the highway and its cold outside, it stards the same odd behavior at idle, after i get off and am at a stop light after the exit. I was told this could be a sensor issue, so i thought I'd inquire about it to see if anyone else gets this odd behavior from their Accord! thanks for the reply

[dderolph]

I've seen that behavior in an 88 Accord that my son bought at an auction about 5 years ago. What we learned is that the coolant was so cruddy (perhaps it had never been replaced) that it was affecting a temperature sensor. Once the radiator was thoroughly flushed, the problem stopped.

I don't know whether that might be a factor in your case, but it does sound like a temperature-sensing issue.

[J00ky]

Well, I got the car around 2 years ago, and a fiew months ago i noticed the coolant level was down, so i added a bit more... but it did this even the first winter when I got it... I personaly never replaced the coolant, and my guess is the car was running on very low coolant for quite a while, I wonder if this could be the reason for it being cruddy..

[dderolph]

If your coolant is cruddy-looking (brown/rust color), it's probably just due to being long overdue for a flushing and new coolant. Perhaps it has never been changed. If so, it's long overdue.

I don't think being low on coolant would cause cruddy-looking coolant. It's just old stuff. Of course, the risk with low coolant level is overheating, which could cause severe engine damage or simply ruin an engine.

[minessa]

I've got a 93 accord that idled the same way for a couple of months. Then it'd die after starting, it usually re-started after 15 minutes or so. Then it just wouldn't start, except sometimes, it'd start after charging the battery. I thought it might be the alternator, but after replacing that & the battery, it still drains the battery & won't start. I was just wondering if you ever found out what to do about it, cuz I'm stumped.

[J00ky]

mine would die as well after starting... so i checked the wirining.. and one of the wires on the distributor was in very bad shape. So I replaced the wires, and it doesnt die anymore, except a fiew times. But I think thats because i released the clutch to early and/or didnt keep the key position on "Ignition" long enough...

[robdog04]

I experienced the same problem on my 1991 honda ex. After researching I found the problem to be the idle sensor. When looking at prices I researched further into diagnosis of the problem. Not only was my coolant in need of change, but my sensor was also dirty, which was due from having to much oil in the engine at previous times. Two bolts and 2 clamped hoses and I had my sensor out. I clened the screen inside and my idle returned to normal temporarily. So next I cleanedthe sensor next to the idle sensor with little ease also. That seemed to correct the problem. I have had no problems in 2 months of driving and spent $1.89 on choke and carbeurator cleaner and about 1 hr of time. My problem was that the idle would surge up and down, up and down in park and when starting in the morning. Compare to $249 for a new sensor and Well this a great alternative!

[J00ky]

robdog04: Would this up and down happen during normal outside temperature? or only when its cold? and in either case, would It go away after the engine warmed up or would it keep doing it no matter what?

[J00ky]

Because this only happens to me in the winter. And Canadian winter being particulary fierce, i would say it starts at 0 degrees celcius (water freezing temp) any temperature over that it works fine, anything under, and it goes up and down... and as i said before, the up and down lasts longer depending on how cold it is. Once it never stoped , because it was something like -35 celcius outside.

[robdog04]

Originally Posted by J00ky

robdog04: Would this up and down happen during normal outside temperature? or only when its cold? and in either case, would It go away after the engine warmed up or would it keep doing it no matter what?

You know what I'm not sure! After replaying my situation I do recall after it would warm up. It would slowly idle back down to 750-800 RPM. But it would take longer than usual and sometimes it would idle higher than normal after warming up. Causing me to think that there was some kind of obstruction in the sensor. So I cleaned it and the one to the right of it. Been A O.K. ever since. I do know I'm not a mechanic LOL. 10 degrees below freezing temperatures is something that we do not get much of in N. Alabama. Sorry I can't help any further. I am replacing a headlight on the drivers's side next week if you or anyone has any tips on the quickest, errorless, way to do it.

[robdog04]

Originally Posted by robdog04

You know what I'm not sure! After replaying my situation I do recall after it would warm up. It would slowly idle back down to 750-800 RPM. But it would take longer than usual and sometimes it would idle higher than normal after warming up. Causing me to think that there was some kind of obstruction in the sensor. So I cleaned it and the one to the right of it. Been A O.K. ever since. I do know I'm not a mechanic LOL. 10 degrees below freezing temperatures is something that we do not get much of in N. Alabama. Sorry I can't help any further. I am replacing a headlight on the drivers's side next week if you or anyone has any tips on the quickest, errorless, way to do it.

Also the part to the right of the Air Idle Control Sensor is some sort of valve not sure of the name. First I sprayed the cleaner into it while running and it shut the engine down. Then I took it off and cleaned it thoroughly and thats when everything started working properly again.
There are two small screws holding a small cover on top of the valve, After taking these off you can examine whether or not it is dirty or not and needs to be cleaned.

[J00ky]

robdog04: Well it looks like the sources of our issues with the idle might be different... Im 90% positive this is a sensor/electrical problem because it only does it at a certain temperature range. After the engine is fully warm, it runs flawless... the rpm just locks at 750. But i will check the Idle Air control valve and its sensors, perhaps there is more then 1 piece responsible for this issue. Thanks for the replies!!!

[Damienwc]

I'm having similar problems in my 92 LX......... its recently got cold outside and my idle goes up and down. It will do that for a few minutes when I start it up, but quits after about 5 minutes of idle. I've also noticed that the problem returns when I press my brakes......... i'm wondering if I could be leaking some brake fluid onto my throttle position sensor? For those of you who have corrected your problem, did you also notice the idle up and down when you pressed your brakes?

[AccordCodger]

The brake thing MIGHT be a clue. Braking puts a load on the Alternator (brake lights). Could a weak alternator cause the idle to fluctuate?

[J00ky]

Damienwc: No the breaks dont change anything in my case.. after it stops going up and down... or even during... i press the break... it doesnt make any difference.