95 Civic - Light Pinging

[JZiggy]

Thanks for the bump, SlimJim.

I tried Shell gas with no effect. I changed the spark plugs also with no effect. The problem seems to be intermittent however. One day last week it would practically knock when going up a small hill, the last couple of days I barely heard any pinging at all.

I put in an order to Amsoil yesterday for some power foam and some PI juice. When I get nearer to the end of my OCI I will run both of these products to see if I can knock loose some carbon.

Still need to check the timing...

Side note - the Civic uses about 1 qt per 2000 miles using 5w30. I'm interested to try some 15w40 I picked up to see if that curbs consumption. Any thoughts?

 

[cchase]

You say it recently started pinging. Is it possible that your usage has in some way changed recently? Many vehicles will ping if you put them under medium/high load at lower RPM's, as Vikas mentioned.

You seem well versed in all of this so you've probably fiddled with the variables, but I thought it was worth mentioning.

It can only retard the timing so much, after all.

 

[JZiggy]

It's certainly possible that my usage has changed. But what is interesting is that it tends to ping under low-medium load at rpms between 1200 and 2500. For instance, if I am going gently up a grade it will begin to ping. I then push the gas pedal further down and the pinging stops.

 

[cchase]

I'd be interested to see knock counts and the timing advance.

 

[bigmike]

Originally Posted By: JZiggy
It's certainly possible that my usage has changed. But what is interesting is that it tends to ping under low-medium load at rpms between 1200 and 2500. For instance, if I am going gently up a grade it will begin to ping. I then push the gas pedal further down and the pinging stops.


Strangely enough, my truck has been doing the same thing at low RPM (usually 1000-1400 RPM) for the past several months. I checked for a vacuum leak - nothing found. I tried different gas. I ran Regane through a tank. I use MMO/TCW3 typically, so I stopped using it for a few tanks to see if I was overdosing. I cleaned the MAF, intake, and throttle body. None of those things changed anything.

Ended up running a bottle of redline fuel cleaner through it and it has appeared to resolve the issue (so far) within 1/2 a tank. I'm a skeptical person by nature, so I'm not 100% certain it's fixed, but at least I haven't heard it for the last week or so.

 

[ltslimjim]

Interestingly, enough. My car acts similarly at the same RPMs, perhaps not an actual knock but the vehicle going in/out of lean burn. I have a '92 VX that turns into 'power loss' between 1500-2300 RPMs or so, under light-medium throttle in order to lean the a/f ratio to save fuel. 5-wire wideband LAF(02) sensor, ftw.

Yes, it has an EGR valve/system and a Constant Vacuum Control box with the EGR solenoid and vacuum device on the rear firewall near the fuel filter.

Post back the results of fuel additive and top-end cleaning post oil change(yes, use them just before the oil change, the fuel add 1 full tank to empty prior).

Also, I have used Power Foam then followed up with an idle flush before, either way in the past I'd get some noticeable carbon deposits in the old oil as I poured it up(obviously your catch pan needs to be clean prior or you are seeing other drains crud etc).

When I last used another idle flush, this time Lubro Moly's Pro Line Engine Flush, just before draining the previous oil b4 my current OCI, I saw NO deposits(at least visibly) in the drained oil. The previous times using Power Foam or other idle flushes, I've seen some carbon. I think my efforts to clean up the engine met with 'some' success. At least in deposit removal. I haven't removed the valve covers for pics yet, but plan to.

I mean, checking timing relative to advance under load would be interesting. If this is indeed sensor controlled, the efforts at deposit removal should be helpful.

 

[JZiggy]

So I think I found the issue...

I was doing some reading on this amazing site (BITOG) about other people's issues that are similar to mine. Many responders suggested that these symptoms could be indicative of a weak ignition system.

The pinging has slowly gotten a bit worse, so I went ahead and ordered a better quality ignition coil (Delphi > Beck Arnley) and spark plugs wires (NGK > Autolite). When I was taking things apart, I noticed that the screw holding on the distributor rotor was LOOSE.

I snugged it up, replaced nothing, and now the issue is 99% gone. It will still give a little ping every now and again, but it has almost totally corrected the issue.

I will still try the new ignition components and see if that gets me the last 1%.

 

[mechtech2]

I never heard of weak coils making a car ping/spark knock.
I don't see the connection or the reasoning.

 

[ltslimjim]

^If connection is loose 'enough' on a particular model, it could perhaps generate a chain reaction of symptoms where the firing isn't clean.

 

[Pablo]

Originally Posted By: mechtech2
I never heard of weak coils making a car ping/spark knock.
I don't see the connection or the reasoning.


Don't think he wrote "weak" coils, but a lousy connection could certainly cause ignition problems.

 

[JZiggy]

I don't pretend to be a mechanic. But I have heard that if there is something wrong with the ignition coil it can manifest itself as intermittent pinging. Perhaps this is only true for Hondas? I'll report back after I've driven a while to be sure that it really is fixed, though it certainly seems to be now.