I'm with Bill, can you make up a video? Might help us narrow in on the problem.

Did you write down the codes before you cleared them. They might give us an idea of what'* up.

In our defense..we kinda asked for you to get the codes...not clear them

Okay so I started the car up this morning and after 30 seconds or so the check engine light starts blinking. I put the reader on it and I get the same misfire in #6 code. The oil pressure is still staying at 60 with no fluctuation in regards to rpm. But the boost is acting normal.

More Bad News

So I figure I would check the coil even though they put a multimeter on it and Auto Zone. So I switched the #4 and #6 wires and now the car won't start. I switch the wires back the car still won't start. Plenty of juice and lots of clicking but nothing else. This in some way has something to do with the lack of oil pressure movement on the gauge. Anyone want to buy a 99 SSEI that needs a motor? Or anyone have a motor for a good price?

Thanks, Jack

What'* clicking? The starter? Relays clicking?

Jack..hopefully you take this the right way, but you might be part of the problem bud.

You cleared the codes when we asked you to pull them and tell us what you pulled.

Then purposely changed the #4 and #6 wires when the suggestion was #3 and #6 with the reason behind it being ok to swap 3 with 6 You purposely changed firing order to something that doesn't work. I know with a little throttle these engines will usually start on 4 cylinder, seems kinda counter productive to do it on purpose though.

I'd really like to help you. Please follow the below

1. Fix the firing order if you haven't already.
2. Look at the #6 plug wire and ensure it is not laying on metal where it could arc out and that it'* not touching the O2 sensor or wiring. If it is a problem, correct it.
3. Try and start the car using a very little amount of throttle. If it doesn't start put the pedal to the floorboard to clean out the cylinder while cranking. As soon as it catches, let it back up. Do not over rev the motor.
4. See if your code reader still has codes stored. If so, please post them.

If you are serious about selling and we can't fix it up with you. Where are you located. I may be interested if it'* local.

Bill I thought 3 and 6 made sense because of it being on the same coil but I swear I read 4 and 6 (on a different thread). The code was P0306 misfire 6 cylinder and P0440. I have had the P0440 forever and actually fixed it last night, a vacuum hose was off of the canister below the computer. I hear what you are saying about the wires but I got a misfire in #6 before and after I changed the wires an plugs so I don't think that is the problem. I appreciate everyone'* help and I will not take anything the wrong way. I think we are looking at the symptoms a little to much and not the cause. What I mean is why would my car bang hard while backing up at two different times of the day when first started and why would my oil pressure not fluctuate and stay at 60. Sure gauges and sending units go bad but rarely do they go bad like this and at the same time as these other problems. I mean the gauge goes top to bottom when it starts the needle moves very smoothly as it should but when the car is running the pressure stays at 60. Now what about the cat or the oil pump? What if someone put something in my tailpipe how would my car react? I am getting a charger here shortly and am going to try and start it up. Once it is started I will shut here down and switch the correct wires this time and see if it kicks out the same code. I guess I am hoping for a P0303 this time which would mean a bad coil. Now something i failed to mention is that the low oil light came on a couple of times the last 2 days but went off rather quickly. I check the oil and it was a quart low and I had planned on bringing it in. I added a quart yesterday and now it is full, well according to the dipstick. If I get the car running and still get a misfire on 6 what should I do next. Compression test the cylinder? Can it be a bad injector. I have no problem replacing an 02 sensor but put $230 in the car yesterday that I might not ever be able to get back. The sensors are $70 each. Again I appreciate everyone'* help and I am located in KY 42301.

Thanks, Jack

I would listen to these guys when it comes to diagnostics.. They tend to be very knowledgable and have helped many save alot of money

Well the misfire moved to the #3 cylinder so I am going to get a coil. Will update when I get it installed.

Thanks

We still don't know what the bang was, drive train, engine, back fire. Also, a video of the engien running would help.