em1 misfiring and now won't start

[Haro540air]

Hey guys, I have a 1999 civic si with the b16a2. The other day I was going up a steep hill and almost at the top my check engine light started to flash as it was misfiring. Lost almost all power and started to studder like it was running on 3 cylinders. As the rpms went down the power loss became worse. I pulled over and restarted the car, it almost wouldn't start and sounded very choppy. Got it towed home, then changed out the spark plugs and wires. The cylinder 4 spark plug (by the timing belt) was burnt up more then the rest, smelled like gas. I also noticed this last time I changed the plugs. So I tried to start it again after this and it wouldn't start. Sounded like it wanted to but couldn't, the starter began to smoke from stress. There's a couple things it could be but need to narrow it down. Any input would be appreciated, thanks.

 

[daperez13]

Did you pull the code(s) before doing any diagnosis?

Continue checking the easy stuff first (like you did with the spark plugs and wires), move on to the cap and rotor and then the coil in the distributor. Then follow up with the injector and cylinder compression. Remove that spark plug, still connected to the spark plug wire, ground it and visually check the spark; compare it to the others. If it happens again with new spark plugs, move the suspected bad injector to another cylinder and see if the misfire follows the injector. If it does, you most likely found your issue. If not, more troubleshooting will need to be performed.

Also, check your oil level. It may seem irrelevant but low oil level will deactivate your vtec and throw a cell in certain conditions. If you have access to a scanner that has live data capabilities, monitor your O2 sensors to see if they are behaving ok.

 

[HeX]

I'm more inclined to think this was a fuel delivery issue being that it occurred while driving up an incline. If you were low on gas at the time then this furthers my first thought, moreso if it hasn't happened again since that incident. Either way, you should definitely have some sort of code if it wasn't a low fuel issue where then pump couldn't reach the remaining fuel in the tank. The 4th cylinder thing could be coincidental.

Also, what brand of spark plug wires and plugs are you using? Have you ensured they're gapped at .044? Doing the aforementioned plug swap test is also a good idea.

As for daperez13s suggestion, low oil will only cause a check-engine code but it wont cause your car to misfire or shut off.

 

[Haro540air]

Thanks for the great input guys. I checked the spark and it was barely getting any, if at all so i changed out the distributor (and plugs/wires as i mentioned), after this it was getting great spark. But then still, the car would not start and has oil plus plenty of gas. Every time I attempt to start it up, i pull out all the spark plugs and they smell like plenty of gas, leading me to think it is getting fuel just fine. Checked timing, its on point. So after failing with everything else I gave it a compression test. It was only getting about 10psi of compression in cylinder 1 (by the timing belt, i was mistaken in my original post), which is the same cylinder where my spark plugs would keep burning up in, as i mentioned above. Cylinder 2 was at about 110psi, cylinder 3 at 95psi and cylinder 4 (next to the dizzy) was reading full compression at 210psi. It always sounds like it wants to start up, like a cylinder is fully firing but the rest cant produce enough power/compression. And this test confirms this theory. I'm thinking that its piston rings because my car has been burning oil for a while now as well. I've pretty much ruled out the head gasket as i have never lost a drop of coolant. Any help or advice of how to proceed would be greatly appreciated, thank you!

I'm more inclined to think this was a fuel delivery issue being that it occurred while driving up an incline. If you were low on gas at the time then this furthers my first thought, moreso if it hasn't happened again since that incident. Either way, you should definitely have some sort of code if it wasn't a low fuel issue where then pump couldn't reach the remaining fuel in the tank. The 4th cylinder thing could be coincidental.

Also, what brand of spark plug wires and plugs are you using? Have you ensured they're gapped at .044? Doing the aforementioned plug swap test is also a good idea.

As for daperez13s suggestion, low oil will only cause a check-engine code but it wont cause your car to misfire or shut off.

im using ngk plugs and wires, which ive never had a problem with. They are gapped correctly and i checked to make sure the distibutor was installed correctly with a method that would take too long to write out..and spark plugs all smell strongly of fuel after attempting to start it, so it seems as if its getting plenty of gas

 

[HeX]

... I gave it a compression test. It was only getting about 10psi of compression in cylinder 1 (by the timing belt, i was mistaken in my original post), which is the same cylinder where my spark plugs would keep burning up in, as i mentioned above. Cylinder 2 was at about 110psi, cylinder 3 at 95psi and cylinder 4 (next to the dizzy) was reading full compression at 210psi...

A faulty piston ring or rings definitely sounds like a strong possibility considering your recent findings.

 

[daperez13]

Given that you only have 10 psi on that cylinder, this may not prove much but pour a cap-full of oil through the spark plug orifice into that cylinder and redo your compression test. If you yield better results, this will further indicate that the issue is indeed your rings. If the oil does not improve your readings, it could be your valve(s) or a crack somewhere. At this point, you can perform a leak-down test to pinpoint where in your engine the air is escaping, which should reveal what part of the engine is the culprit. Keep in mind that if neither the compression or leak-down tests are performed correctly, you could be trying to fix something that may not be defective.