Victor Jónsson

Hi guys.

My car has been having increasingly bigger problems these last couple of weeks.

The problem (although big problem yesterday and today) is that at mostly lower rpms, the engine hesitates/coughs/misses and will sometimes just... quit

And the problem is it's intermittent. (I've read alot about the main relay IACV etc)

So bear with me as i open yet another thread

Main relay
Today the car was really bad and I could hear the main relay click when I pushed the clutch down when coming to a stop at at light and the engine quit.

This happened a few times and I could here the main relay click at least some of the time.

Now, the main relay solding looks ok as far as i can tell. And I've just completed testing by instruction of the Haynes manual. According to that, it's ok.

But should the main relay be clicking all by itself after the engine has started or is there something that signals the relay so that it thinks that it should shut off? Maybe the IACV can't idle the car properly, the engine quits and thus the relay?

Usually the car starts again when it has died. But today I had to try 2+ times before it started.

I guess what i'm asking is if i should reflow the solders on the relay anyway or try to get a new one.

IACV
I know I need to clean my IACV and I'm going to do that a little later today.
I took it off the other day and the little filter/net was completely destroyed. Just some frays around the opening.

Do you think that the IACV could be causing the problem or maybe the combination of the two?

So I'm going to clean the IACV and I'm probably going to need a new one. Is it possible to open it up more or are those two holes the only way?

Should I:

• Clean my IACV and buy a filter/net
• Buy a new IACV

Things I've already done

• New distributor cap & rotor
• Relatively new sparklugs (not driven far)
• Relatively new open/conical airfilter (not driven far)
• Oil cleaner + New oil and oil filter
• New fuel filter
• Bell Add service clean (throttle body cleaner + fuel additive)

FYI: The car was sitting for a few years up until february. I had engine problems similar to this that the new distributor cap and rotor fixed, until now.

UPDATE: Sorry, I omitted all information about my car

Honda Civic ED7 1991
1.6L engine - D16A9

Any help greatly appreciated. See attached some pictures of the relay and IACV.

BiGZ

That relay has already had solder added to it (stock they came with very minimal solder,which leads to vibration + thermal contraction/expanding to cause cold solder joints. The other problem main relays develop is the lil contact points on the relay bobbins themselves-get a used relay from a junkyard + re-solder it. I used to sell em on ebay... Or,bite the bullet + pay dealer price for brand new relay (which'll do same after say,10-20 years prolly) G'luck!

Victor Jónsson

Thanks for your reply BiGZ. I'm looking around for a new main relay and a new IACV or just the filter.

Well, I have an update.

The car ran fine for a day after cleaning my IACV.

Then it began again the next day. Ran fine in the morning, badly later in the day.

This morning it was really bad. But as usual only when the car had warmed up.

And it was a bit different than last time.

This time I could not hear anything from the main relay (other than a click when first starting).

It will hesitate like crazy and finally loose all power. Pressing the gas pedal does nothing. Although I can hear (what i think is) the air filter sucking air when I push the pedal. I can still read the RPM.

I find this occurs only when I'm just touching the gas pedal (just about holding it down to cruise). Not when I press the pedal more to accelerate.

Then either of two things happen:
- The engine just dies completely (RPM drops to 0)
- The engine suddenly comes alive again and I could hear a "pop" from behind the car.

When coming to a stop the engine will either quit or just run as usual.

After awhile of these problems, the car ran fine the rest of the way to work. (Route is about 15 km and takes about 20+ minutes)

The weather is cold, the relay didn't click at all and I've cleaned my shitty IACV.

Any ideas what could be wrong or what I should check next?

Thanks for the help.