Changed plugs and wires, not all cylinder firing

most likely a problem injector in each cylinder or wiring for those injectors

Hey 94 TOY...

When did the problem start? Before you changed the wires and plugs? Or did it start, AFTER you changed the wires and plugs? Did the problem remain the same BEFORE & AFTER you made the changes?

1 - If the TOY ran fair to Okay before you did the work, then you may have done something wrong when you made the cahages. Check for correct plugs and firing order. Check for cross wiring. With engine runing pull one plug wire off each plug one at a time. Each pulled plug wire will slow down the engine. When you pull a plug wire that doesn't react and does not make any change ON or OFF that cylinder Plug.
Then that cylinder is not firing.

2 - Check for spark at that wire. If you do-not have Spark there, But the other wires do... the wire going to that cylinder is BAD.

3 - If you have the correct firing order and spark at all cylinders then the cylinder that did-not change the speed of engine has a compresstion problem. Bad valves, Piston or rings are bad... Major engine work and Major repair bill for the repair job.... GOOD LUCK....

You said you changed the coil pack and the wires but didn't mention the plugs. Try moving one of the plugs to a different cylinder and see if the miss follows it. It could also be the ignition module. (the thing the coil packs mount to.)

Invalid test. When plug fires, the wire shoots around 40,000volts. When not firing, there is no current in the wire.
Try switching the misfiring plug wire with another that is firing. Switch them both at the plug and at the coil tower. If that was a bad plug wire, the misfire will now be on the cylinder where you put the suspect wire. This will confirm a bad plugwire.
Good luck.

Firing order is 1, 5, 3, 6, 2, 4. Number 1 cylinder is up front. Why would you need the firing order, this engine does not have plug wires, each plug has its own coil pack, each coil pack is controlled by the computer.

Hello mikew564.The first diagnosis was number 2 or 3 cylinder not firing. Once you changed the coil, the check engine light went off. When the light came back on again, did you get it diagnosed again to find out if the problem was the same?... 2 or 3 cylinder not firing????

First of all, there is NO extra wire/ground on the coil/ignition wiring (see images below). The spark plugs and ignition plug wiring can be checked for arcing, corrosion, resistance and can be checked for cracks in the insulators or worn electrodes (and spark gap) by a competent mechanic.
If you are having the same issue (2 - 3 misfire), there are several techniques for eliminating the plug wires or spark plugs. Spray water on the plug wires to see if they are arcing. Swap plugs from cylinders 2 & 3 with cylinders 1 & 4. If you still have a 2-3 misfire, check/inspect/examine the coil connector pins & coil harness to the coil(s) themselves.

remove the plug from the #1 cylinder, and install it into the #2 cylinder , and put plug from # 2 clyinder in to #1 plug hole, connect plug wires, and start up vehichle, and if computer shows misfire on # 2 cylinder , then you have a bad plug, possibly porcelin insulator could have a hair line crack in it, hope that this information has helped you.

Hope this helps. The ignition coil:

• changes low-voltage pulses from the PCM to high-voltage pulses.
• fires 2 spark plugs simultaneously.
• has 3 transformers.
  • One transformer fires the spark plugs for cylinders 1 and 5
  • One transformer fires the spark plugs for cylinders 2 and 6
  • One transformer fires the spark plugs for cylinders 3 and 4

Spark plug wires:

• carry high-voltage pulses from the ignition coil to the spark plugs.

The spark plugs:

• change high-voltage pulses to spark at the gap, which ignites the fuel and air mixture.

The firing order is 1-4-2-5-3-6.

ck if you have spark at the coil for that cylinder. check the plug wire closely. if it has spark at the coil, then replace all the spark plug wires.

Problem could be as simple as a vacuum leak around either of those cylinders. A vacuum leak can create a lean fuel mixure condition resulting in a miss fire. One thing to rememeber is that depending on the style of ignition in use. The opposing cylinder's spark plug and wires act as the return path for the unused voltage from the coils firing which is why you are having seemingly unrelated misfires. If either has a problem then the symptoms are shown in both cylinders.