[sancho_mic]

Hi,

I have a Honda civic, 92 model, with manual transmission. It's on carburetor, imported in Cyprus from Japan.

The car is great but lately it started to behave really strange, when it comes to cold start.
I will describe the symptoms, hope it will help you more than it helped my mechanic, even after 4 visits and an early full service that I was hoping to fix the problem.


From few months back, the engine occasionally stops when idle - this happens 3-7 minutes after cold start (how cold can it be in Cyprus these days, when night temp is more than 20 degrees Celsius?).
Occasionally means at each cold start it's either doing this, constantly for 10-15 minutes, or not doing it at all.


These are the exact symptoms:

A) cold start ignition - normal situation: rev goes at 2000 rpm for 5-10 secs, then goes to 1500 rmp, and after 2-4 minutes to 900 rpm (normal idle rev)

1) sometimes, instead of being stable at 900 rmp, the rpm fluctuates, I hear and feel the engine is not spinning "round", but it has some fluctuations/bursts

2) when having these bursts - imagine that I'm driving - engine stops if gas pedal is not pressed and gear is on neutral - for example, when I'm braking and I change gears

3) when driving, the bursts are more powerful on low gear and less noticeable on high gear (on highway). They eventually end in a slightly more powerful burst (hic!) and problem disappears till next cold start :)

If I'm waiting at a traffic light, I noticed that if I rev up to 3500-4500 on neutral, 2-3 times, the problem is overcome instantly but till the next cold start :)

4) Since it started to have these symptoms, sometimes the revs are sitting at 900 rpm constantly, sometimes it's below 900 rpm and I feel the engine/car vibrating


B) engine is hot (i.e I stop for 5 minutes at a shop): when igniting, if I'm not pressing gas several times to maintain the rev, the engine will stop. I tried several consecutive times to start without giving gas, and they all fail, the engine dies, no matter how much I would try


The mechanic only resumed to adjust the revs on several occasions, even after a full service (filters change, oil change, etc... ); the car has good power, good millage - except this issue that drives me crazy...

Please help,
Thanks a lot,
Sancho

[TxGreaseMonkey]

Replace the Ignition Control Module (ICM) and coil:

https://www.askmehelpdesk.com/cars-t...tml#post265896

[sancho_mic]

Thanks a lot TXGreaseMonkey - next week I'm giving the car to the mechanic, dropping it in the morning and taking it in the evening, till he will solve the problem...

When you say coil, you refer to the ignition coil? If yes, then it was replaced by the same mechanic ~6 months ago. The car died during acceleration, and could not make it to ignite again.

Now that you mentioned, probably that was the time when rev at idle started to fluctuate - before that it was always rock stable at 900 rpm... But it never stalled at idle, only recently in the last 2 months...

Any idea how much it should cost to replace the ICM? (is 70-100$ a normal price or not?)
On old cars, during cold start the driver would have to pull a button to ease the ignition (don't know the name). For this honda civic, this is automatic - I presume it's the ICM that handles this?

Thank you again,
Sancho

[TxGreaseMonkey]

Here's how much it costs:

AutoZone.com | Vehicle Selection | Year

[sancho_mic]

Hi,

Hope it helps others with same/ similar problems like mine.

It was the starter solenoid at carburetor. It was not replaced, but cleaned.
The carburetor was also adjusted, and now at idle it does not make grinding sound.

Car has more power and the revs are rock solid, without hiccups...

TxGreasMonkey, thanks a lot for your inputs!
Sancho