Was driving my Civic the other day and all the sudden it acted like it dropped a cylinder. Couldn't keep it above 60. When I pulled over it was smoking pretty bad out of the back of the motor and the idle was struggling.

Anyways, I replaced the spark plugs first just cause i had a spare set. No effect and the problem only occurs when the car is warmed up. Did a compression test and all cylinders are showing 150. Fuel injectors all appear to be working best I can tell. No CEL either... One thing I found weird was plug number 4 was carboned up and it only had 20 minutes of use? I replaced the wire running to it but no effect there either. The plug does not smell like gas and I know that plug wire is sparking so im alittle stumped.

I did notice alittle blue smoke coming out of the tail pipe when I reved it up, so could it be I blew a valve seal or snapped a spring? I figured the compression test would have told me if I did? And it is weird it is totally fine when its cold. Also when it's cold I got a hell of a tap. Before I believed it was just the valves but im wondering if its not a bend push rod.

Any suggestions would be abundantly appreciated!

 

A bad valve stem seal or valve guide wouldn't cause the performance issue. A broken valve or valve spring wouldn't cause an oil burning problem, and it would cause low compression in that cylinder.

 

Thank you for the speedy response and that was kinda what I figured. Just pulled the valve cover and rotated the engine and all the springs seem to be doing their thing.

What would cause that plug to fowl so quick? I work at an auto parts store and a fellow coworker said it might be being drown in oil and then failing? Doesn't look like oil or gas to me just carbon. I will pull the distributor cap and check under there for maybe a cracked tower or something. I know the plu wire is sparking to so thats why im confused. Maybe it is just weak idk.

Could this possibly be sensor I wonder or maybe something haywire in the electrical system perhaps?

 

Check whether injector 4 is stuck open.

Can you say more about this^

 

It hasnt done this since. Think it might have been because it has a small oil leak in the back somewhere. It was just alot of smoke coming from around the oil filter or sending unit area. Also I guess i havent driven it very far so I do not know if it is related or not.

How do I check to make sure the valve isn't sticking open? I just drove it to the gas station and once again it did great til it warmed up then it was erratically losing power and coming back. Acted like it wanted to stall out at the stop sign. Checked under the cap and rotor, it all looks good to me. Coil is relativity new, less then a year. Same with the ICM.

Thanks again for any tips!

 

If the problem only happens after the engine is fully warmed up, then try a test drive with the O2 sensor unplugged.

Any CEL codes? Does the CEL work?

 

Yes CEL does work. Thought maybe it was TPS related and unplugged it. CEL came on. For how bad its running I cannot believe it's not kicking me a code. Why I am worried it is something serious. Will try to drive without the O2 sensor and see what happens. Still doesn't explain why that one spark plug fowls so quick thought. Maybe it is that injector is stuck open.

 

Could be more than one problem.

 

You should stop trying to diagnose ignition system problems unit you check the end of the ignition system. Use a spark tester and see if the spark on all four wires is good, bright and white. You're gonna have to get the car hot, while this problem is happening, and then test it. That's how compression tests work too, the engine needs to be hot. I'm not saying you did it wrong but lots of people do it wrong and you may want to double check.

I know you said theres spark, but it could be weak spark? I dunno. It seems silly to check ignition parts if the ignition system is functioning properly, yakno?

It certainly seems like you're having an oil burning problem if you're seeing blue smoke come out of the exhaust at high RPMs and that's pretty common with 20 yr old honda engines. The oil burning problem would explain the carbon build up on the spark plug and the fouled plug would explain the misfire and loss of power. If I'm right about this, you should do a cylinder leakage test and a modified leakage test to check if the exhaust port holds pressure. Basically, close the exhaust port with a plate, gasket paper against the port, sandwiched under the installed exhaust manifold. Then turn the engine so that the exhaust valves start to open, which pressurised the port and easily tests the leakage of the exhaust valve guide. That's probably but not definitely what your problem is anyway. Lots of people think valve stem seals are going to fix a worn valve guide but that's dumb.

 

I checked the compression both with the engine cold and with it hot. Same with the spark. Knew the cap and such was a long shot but I gave it a look. Unplugging the injectors one by one while it was running made engine run alot worse so thats why I assumed they were working.

Will try what you told me tomorrow when I get off of work. I swear it has had problems before with it at idle like it wanted to die but never when I was driving. Just acts like someone all the sudden yanked a spark plug out or something. Thank you all for your advice!

 

The fix for the problem I discussed is rather time consuming, gotta do timing and a head gasket too. I think you should continue diagnosing possible sensor malfunctions and other stuff like that, the loss of power may not be related to the oil burning issue. My engine burned tons of oil, almost as much oil as gasoline actually. It needed plugs about once a month, but until they got a lot of carbon build up it didn't have any power loss issues.

I dunno how much oil your engine consume, if its actually burning oil and not coolant, etc. For a plug to foul in twenty minutes, its gotta be leaking a lot of oil into the combustion chamber.

Since your problem only happens while the engine is hot, it makes me sort of doubt that it's having a problem because of the fouled plug. Like I said, keep looking at sensors and emissions equipment, all that ****. It could be a lot easier of a fix than a valve guide.

 

I will do that then thanks. Funny thing is unplugging most sensors will make it hesitate but for the most part it runs the same. Havent tried the O2 sensor yet so that's the next one i guess.

 

Besides the O2 sensor, make sure you check the resistance of the fuel injectors. Ron is pretty smart, make sure you check all of the ideas he mentions. He's helped people fix countless civics. Try and get the oil burning/leak thing taken care of eventually too, pollution is bad mmkay?

 

Okay so I tried the O2 Sensor with no success. I was sitting and letting the car warm up again when I heard a pop. That cylinder that keeps fowling plugs blew the plug wire outta its hole. I had noticed this before too when I started chasing this prob, just had never seen it actually go pop like that. I always tighten my plugs by hand til they are snug before using the ratchet so cross threading is not what happened here I think plus those plugs had been in it for 2 years before this started happening.

This probably means its a valve correct? if so how hard is this to fix? I am looking at an 08 civic ill probably be picking up on Saturday, making my 95 an official toy. If this is something more serious then I will have to part with my little civic or if its just valve related I can tear down the head. As usual thanks for the advice guys!

 

The spark plug wire blowing out makes you think its a valve? I don't understand the trail of thought on that. Do you torque your plugs correctly? It wouldn't fall out unless something pulls on it or if the spark plug backs out and pushes it out.

Is your valve cover torqued rite also?

 

Yeah the plugs that were in there had been in there for 2 years before this problem happened and I am always careful threading wise when I swap them out so I have no idea what is going on.

It does definitely run like it is only going on three cylinders so I think I can rule out a sensor or injector at this point. Plug is just fowled with carbon, it is not gas or even oil best I can tell and it chews up every plug I stick in it in a matter of minutes. So short of tearing down that head I am stumped.

PS Yes the valve cover is torqued to spec.