bullmtnbiker

Help! I have an 88 CRX Si with the 1.6L 108 hp engine.

I had the erratic idle problem and it was mostly taken care of by burping the coolant system (Thanks to all the info on this site). With the erratic idle problem the car would go between 1000-2000rpm at idle. Now that seems to be gone BUT

every now and then, I'm sitting at idle and the rpm will go up to 3200 rpm or so and will stay there. After driving a little while longer it will return to a regular idle. It will happen only once on my 12 mile commute to work. Sometimes it will behave the entire time and have a low idle.

Any advice?

Kai

The only possible thing that would cause a high idle like that would be a vacuum leak. Check for cracked hoses and bad gaskets around the intake manifold.

v8guy

Couldn't the throttle plate be sticking and not quite closing all the way? Carbon deposits can cause this, as can crudded up linkages.

Kai

Could be, I kinda consider that a vac leak myself. That would be kinda unusual though.

bullmtnbiker

Hmmm... thanks. It's interesting that I never had the problem with the erratic idle. That is, nothing greater than 2000 rpm.

I've checked the hoses and they seem ok (i.e. still squishy). Is there a way to easily check for the intake manifold leak?

Finally, twice I have turned off the car when this is happening. Both times, the car wouldn't start. After 20 seconds or so without trying to start it, it would start but then go into the 3000 rpm idle thing again. Sigh...

I'll be checking out the hoses again tonight.

bullmtnbiker

v8guy,
I did look into the throttle body and there is a bit of carbon build up in there. Is there a preferred method to remove such stuff?

Thanks.

v8guy

I don't know what the preferred method is, but I usually use Gumout carb&choke cleaner and an old toothbrush to free up stubborn deposits and wipe them out with a rag or paper towels. The gumout will actually start to dissolve the plastic toothbrush but not the bristles. I use them anyway but maybe a wooden brush with brass bristles might be a better idea. After cleaning out the throttle body you will probably want to lubricate the throttle shaft pivot points with a light oil or spray lube. Not too much or it will just gum up and collect dirt. Clean and lub the linkages also and make sure everything is working smoothly. More than one "hanging idle" has been caused by a carboned up throttle body, however, as mentioned, vacuum leaks are also likely suspects. Replace any vacuum hoses that even look questionable. Another thing you might want to check out is your PCV valve. (I assume Honda's have one, my knowledge of automobiles is very general and not Honda specific, in fact, I know very little about them as I just got my first one a week or so ago). The PCV valve is supposed to be replaced at every tune up but often gets ignored.

Pete

I know it's kind of off topic, but how did you "burp" your coolant system? I am having the same idle problem where the RPM's jump between 2,500 and 1,000.

bullmtnbiker

There is a really good thread somewhere on this. Anyway, this is what I did. Engine off. Take radiator cap off. Move heat setting on hvac to hot. Turn on car. Let it run until the fan turns on twice. While the fan is NOT running the engine will force some of the radiator fluid out the top. When the radiator fan turns on, it will pull the radiator fluid back in. When this happens, it is important to keep filling it up. Otherwise, you'll introduce more bubbles. Trust me on this one. Anyway, you will see bubbles coming out of the top of the radiator if you have bubbles. After the second time the radiator fan turns off, turn off the car and replace the cap. You're done.

Also, make sure you put something under the car to catch some of the excess coolant that gets displaced. You can minimize the amount of spillage by starting with a reasonably warm engine. Make sure you remove the radiator cap only when the car is off.

Now if I could only solve this other weird problem...

jdm498

i use to have the same problem with my 87 crx but it was a carb. model and there was a release valve on the back of it .I also adjusted the idle and but that did not work.if your going to clean the throttlebody i would use winns throttlebody cleaner "it is the bestest".spray most of the can in and idle that biatch to remove the carbon deposits.hope this helps if you even read this.o ya and do check for vacum leeks .. :coo: