Mystery problem

ECM = Engine Control Module (aka engine computer).
Only testing of various systems will reveal where the problem is. There are some components which are involved, directly, with spark production. The distributor houses three sensors which send signals to the ECM. Also, within the distributor is an Ignition Control Module (ICM) which controls spark production, and the ignition coil which produces the spark, which goes to the spark plugs.
I suppose that this would qualify as Mechanics 103.

Thanks :slight_smile:

You could replace everything in the ignition (spark) system, except the ECM, by replacing the DISTRIBUTOR. The distributor contains three sensors, and the ICM, and the ignition coil. It costs $280 for a re-manufactured one (from Auto Zone Auto Parts, directly). If your mechanic has rapport has his auto parts supplier, as I do, he could get the distributor, try it out, and if it didn’t work, take it back, and tell them, “Sorry, it didn’t work”, or “wrong application”.

Thanks for the tip. I got one quote for a distributer at about $400 (maybe that was new). As I mentioned in a previous post, I was going to try a garage recommended on this website. I plan to bring all these suggestions with me.

Thanks again

Hi there
Not sure if anyone will remember the girl from Canada with the CRV check engine light problems but here’s the latest. I finally got a chance to take the car into Mistor/Senger motors, a garage that I found through this website. The man was very nice but as with everyplace I’ve been, he couldn’t tell me for sure what was causing the problem. He recommended replacing the distributor cap and something called the distributor rotor. He charged me a very reasonable price to do this. The bad news is, when all was done, the engine light was still on. I decided to call the place in Canada where I get the emission testing done and ask their advice. I had been under the (false) impression that having the CEL on would automatically fail the car. They told me this wasn’t necessarily true. So the good news is that I PASSED the emission test which totally solves my problem about getting my new tags etc and keeping me on the road for another two years. My plan was to totally let it go at that. My concern now is that the car, in my opinion, continues to idle slowly. It has never stauled out but since I spend a good amount of my time sitting in the tunnel, I worry that there will eventually be a first time, and it won’t be good. The man at Mistor/Senger motors thinks the timing belt is the next logical step. As far as I know this has never been changed in my close to 10yr old vehicle. The hard part …to do that, with the water pump (which he said might be necessary) will be close to another $600. Does anyone think this is a worthwhile undertaking?

Maybe the codes weren’t cleared to turn the CEL off. Maybe go have them cleared at Autozone and see if it comes back on.

As for the timing belt - if your car has more than 100,000 miles on it and you’ve never changed it, it’s probably time, unfortunately.

Thanks for the reply. When I picked the car up the light was actually flashing as opposed to being steadily on, as it had been. But after a while it went back to being steadily on. The mechanic offered to let me come back to read the codes again and see what they said but I didn’t have time to go back in yet. Thanks for the info on the timing belt. The car has 225,000 kms on it which is about 120,000 miles.


For the sake of your Honda, it is imperative that you read your owner’s manual about the required maintenance. In the owners manual you will find the exact info about when you need to change the timing belt. In general, the newer Honda engines with a timing belt require they must be changed at 105k miles OR 8 years WHICHEVER comes first. Based on the “time” metric alone, you’re way overdue. Just to put things in perspective: a broken timing belt will destroy your engine, to the tune of $3000-$4000 US dollars.

Going from my previous list of possible trouble spots I suggest you have the EGR valve cleaned to see if that clears the misfire trouble. I think that is the best suspect for the trouble.

I Hope It Is “OK” That I Quote OK4450, One Of Our Regular Technicians On This Site.

Recently while referring to another 2001 CRV and a question about timing belts, He said, [i]"The belt should have been changed about 4 or 5 years ago. It may last another 10 years or it may snap tomorrow. No one knows.

Another annoying little expense that is overlooked, due to a foolish factory recommendation, is the valve lash adjustment. This should have been inspected and adjusted as necessry about 65k miles ago; at a minimum.[/i]"

Here’s what I have found -
Speaking of valves, there is a Honda TSB (Technical Service Bulletin) written for Honda Technicians, that explains a problem with 1999, 2000, and 2001 Honda CRVs. The bulletin discusses rough idle, hard to start, poor performance - or - MIL comes on with DTC PO301, PO302, PO303, PO304 - or - PO172.

The possible cause is that “one or more exhaust valves has receded into the cylinder head”. The fix is to inspect the valve clearance and, if necessary, replace the cylinder head.

The bulletin says to check and adjust the valves and if they are within specs then look for other possible causes like ignition, fuel injection, etcetera.

Out of warranty repairs for head replacements were eligible for Honda Goodwill consideration, but the request and approval had to be obtained prior to the work. This bulletin is now 5 1/2 years old, so I don’t know what the chance are of any Goodwill and I don’t know if this car was maintained in regards to valve lash maintenance.

Has anybody done a thorough compression test on this Honda ?
Can one of your technicians access this TSB ?


Thanks everyone for all of the information and suggestions. Now my head is spinning even more! lol Badabing2010, you’ll be happy to know that I have scheduled to have the timing belt done on Tues. Please know that to the best of my ability I have taken good care of this vehicle but short of reading the entire manual, I only know what needs changing when I’m told by a professional. To the best of my recollection, I’ve never been told about the timing belt but I know ignorance is no excuse. Cougar, I will inquire about that EGR valve and Common Sense Answer, if you look back near the beginning of my posts I did say that a Michigan Honda dealer told me of the cylinder head problem with the Honda’s but when I inquired at my Canadian Honda dealer they weren’t aware of this problem so I hoped it was a U.S issue. The car does idle somewhat slowly but I wouldn’t call it rough and I don’t have any of the other symptoms you described (hard to start, poor performance etc). I don’t know if anyone has done a ‘thorough compression test’? Thanks again for all the info. Will update after the timing belt is done.

One Caveat . . .

. . . Sorry to spin your head some more, but that’s how these things go sometimes. You enter a state of chaos and have to work your way out.

I agree that the timing belt needs to be replaced now if it has one and it’s never been done. A timing belt replacement by itself should not “fix” anything or change the running of the car, unless it has “jumped” a tooth and changed the timing.

Since a valve / cylinder head issue is a possible problem that needs to be addressed (because of a factory defect that I discussed previously or because of neglect in having the valves adjusted in a timely manner), I’d have this checked prior to or in addition to the belt replacement.

The reason for this caveat is that these 2 procedures (belt replacement & head / valve replacement) “overlap” (one procedure involves part of the other procedure). This means that doing one and then later doing the other will cost you more labor than doing them together if it turns out it needs it.

My recommendation is that before doing the timing belt, have the head and valve lash checked and compression tested and have them verify that the engine timing was either “on” the mark or “off” and that the valves are functioning normally. In other words, continue to have the original problem diagnosed while they’re working on the mechanical parts of the engine.

Also, speaking of “overlapping” labor, it’s usually prudent to replace the timing belt tensioner and water pump with the timing belt. I just did a timing belt on my own vehicle and replaced those items mentioned and an idler pulley and both camshaft and crankshaft seals. I virtually replaced everything inside the timing belt cover except the sprockets.

Failure of any of these worn parts can create a need to have the timing belt replacement done all over, again.

Also, I’d have a Canadian Honda dealer do you a favor and search their Technical Service Bulletins for any bulletins that specifically pertain to your problem, as discussed. Some nice service department person should be willing to do this for you as a favor.


Dear CSA
I don’t know what to say? This is all just too much to take in. When the MI Honda dealer told me about the cylander head possibility, he said it would be a $4000 fix if that was the problem. The bottom line is that I’m not spending that kind of money on a 10 yr old vehicle. If the car had failed the emission test last week, I would have been on the market for a new car. My CRV has been GREAT but I’m not going to start pouring ridiculous amounts of money into it at this point in the game. The mechanic I found through this website is very helpful but even when I print out all these suggestions I’ve received and take them with me, it’s not easy for this nurse to try to tell these people what to do with a car. If I ask him to ‘have the head and valve lash checked and compression tested and verify the engine timing’…how long will this all take? He’s already told me it will be close for me to get the car back the same day doing the timing belt (oh and he already suggested the water pump combo). I work in Detroit but I live in Canada. It’s not like I have a lot of options when I’m without a car. I TRULY appreciate all the help. It’s just all getting a little too overwhelming.

He recommended replacing the distributor cap and something called the distributor rotor.

Those are two inexpensive distributor “accessories” I suspect the problem is the distributor itself.

I agree the timing belt should be replaced if you don’t know its age and mileage. Same with valve adjustment and any other routine maintenance in the manual.

First of all, drive to any inspection station before your inspection expires and ask if they can inspect your car as they would normally but without removing your sticker. Pay the fee. If they can do that and let you know if your car will pass or fail - as they would were you just interested in buying a car - you can assume that the problem will not cause your car to fail unless just the actual occurence of a Check Engine light merits failure. If a station tells you the car will pass inspection, guess what you should do.

Based on your experience with various diagnostic and repair/replacement attempts, this is what almost certainly happened each time.
After each “repair” the Check Engine light came back on I’d guess after two trips. Does that sound about right? If you disconnect your battery yourself, the computer will reset and then re-establish engine conditions after two start and stop cycles. In the meantime your “Check Engine” light will be silent.
The main question is does your car meet emissions and safety standards? These are strictly defined. Find out what those standards are first, and pay a few bucks to have your car independantly evaluated strictly in terms of pass/ fail. Find out if there is any governmental help in the event of abuse in the inspection process.

Otherwise, you report no real problems except a slow idle, and nothing of the “multiple misfires” which would have been the basis of your question and complaint in the first place. You really can’t miss even a single cylinder misfiring, especially if you are used to a smooth running engine, and especially in drive at idle speed. It’s like a hiccup. Can’t miss it.
Good luck.