Problems After Changing Spark Plugs

[MidTownMadness]

I changed my '93 ES 300's spark plugs, plug wires and distributor cap with rotating arm. I'm having major problems after the job. I'd be very grateful if anyone could give me an overview of the correct procedure to changing all of these things so I can ensure I did the installation correctly or give any advice on what might be going wrong with my engine. The details are below.

To be clear, here is the history:

My car's RPMs would momentarily drop when I would let off the throttle when driving down the road. I thought it might be the spark plugs and knew I had to change them soon anyway so I went ahead and bought all the parts. I replaced all plugs(platinum tipped), the plug wires, and distributor cap with the rotating piece inside. After installation I started my car and almost instantly the "check engine" light came on and then the engine died. After starting it up again, I was able to get it to idle, but when putting it in drive it dies. When giving it gas the RPMs seem to waver up and down a few hundred revs. Smells like the mixture is running rich, could that be a misfiring plug?

Here are my theories:

1) Missed a step or installed something improperly when changing plugs, wires, and cap.

2) Already present vacuum leak that I might have made worse when fidgeting with the back plugs

3) Air sensor malfunction causing improper mixture and subsequent engine flood

Any input would be much appreciated. I'm hoping to figure this out so I don't have to take it to a shop.

Best,

Andrew

[Messerchmidt]

ohh boy...you should have done one thing at a time and tested it each time. could be a bad distributor cap. put the old one back on and see what happens

[ppine]

Sometimes a sp wire gets replaced wrong and changes the firing order.