QuestionOk, I removed each of the spark plugs to ensure that they were gapped properly and that there wasn't anything fouling the plugs. I also unplugged each of the spark plug wires one at a time with the engine running. I had two that did not change the idle of the engine at all when removed. On the forward bank it was the one on the far left as you face the engine. Also the center cylinder on the rear bank. All of the plug wires are getting fire though. I also disconnected the injector harnesses for the forward bank near the radiator. The harness for the injector for the cylinder on the far left as you face the engine did not effect the idle at all when removed. This corresponded with the spark plug wire which did not effect the idle when removed. Do I need to change out the wire harnesses for the injectors?
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Thank you for the quick response to my question. It is great to get to talk with someone who is willing to help those of us who are not mechanically inclined.
I have done some more troubleshooting and found something that I didn't know last night. I started the car and let it warm up. I noticed that just below the exhaust manifold below the B2S1 O2 Sensor the exhaust components were glowing red hot. Past the B2S2 Sensor everything looked normal. The shroud around these components was not glowing red hot only the component under the metal shroud. The schematic that I looked up on hmaservice.com states that the catalyst is between B2S1 and B2S2. Is this significant?
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I am driving a 2000 Hyundai Sonata V-6 with 88,000 miles. My check engine light came on last night, but the car was running fine. This morning I started my car and it idled very rough. When I put the car in gear and started to drive it accelerated very poorly at at times acted like it would die when I came to a stop. This is a siezed vehicle used by the government and I am trying to save the taxpayers a few dollars by diagnosing this as much as possible before we go to spending alot of money. Could this be caused by a vacuum hose or an O2 Sensor?
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It's possible that it's a vacuum leak or oxygen sensor, but since you say the car was idling roughly and accelerated poorly, it's more likely to be a misfire issue. But in fact, there are a large number of things that can cause your check engine lamp to come on and the engine to not run properly. You should start by having the diagnostic trouble codes read. AutoZone has advertised that they'll do this for no charge.
If you follow-up with the trouble codes, I'll tell you what they mean and help you repair the issue.
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The glowing was the catalytic converter. This was probably due to an ignition misfire causing unburned fuel to enter the catalytic converter. If the engine is misfiring so badly that the check engine lamp is flashing, you should not drive the vehicle-- driving the vehicle with a serious misfire can damage the converter.
Bank two is the bank near the radiator. If that's the case, you can check the cylinders there for misfire one by one. Remove each injector connector and place it back. The engine should run rougher when the injector is unplugged. If it doesn't, that cylinder is misfiring.
AnswerOkay. The rear bank has cylinders 1, 3, and 5, and the front bank has cylinders 2, 4, and 6. So your misfires are on cylinder numbers two and three. Most misfires are caused by secondary ignition components (plug wires, spark plugs, ignition coil). Since cylinders 2 and 3 are fired by different coil packs, it's unlikely that this is an ignition coil issue.
Start with cylinder number 2 since it's easily accessible. Look at the plug end of the wire. Do you see any carbon tracking on the plastic part that goes down into the plug hole? If so, the wire is arcing. If not, reinstall the wire and just set it on the plug without clipping it back in place. Start the car and go back to the plug wire. Since you already know you have spark coming out of the coil, there should be spark coming out the end of the wire. Gradually lift the wire off the plug until you can see into the plug hole to see the spark coming out of the wire. If it's coming out of the side of the wire, the wire is arcing. If it continues to jump out of the end of the wire (or stops sparking once it gets too far away) as you continue to pull the wire off the plug, then the wire is probably okay.
If you determine the wire is okay, swqp the #2 plug with the #4 plug and recheck to see which cylinder in the front bank is misfiring. If it's now #4, then the spark plug is bad.
If you determine the spark plugs or wires are the cause of the problem, you should replace the spark plugs and wires. You'll need to remove the intake plenum to replace the plugs and wires. Doing both at the same time generally prevents needing to pull the plenum off again after a short period of time.
