The easiest is through the fender wells. You can even take off the tires to get more room. It is the easiest way I found anways.
how do you change the spark plugs on a 1991 q 45 infiniti
To change the spark plugs in a 1991 Nissan Stanza, first, remove the ignition wires from the spark plugs, noting their order. Use a spark plug socket to unscrew the old plugs and replace them with new ones, ensuring they are gapped correctly. For the distributor cap, locate it on the engine, then disconnect the wires and unscrew the cap. Replace it with a new cap, ensuring that the wires are reconnected in the correct order.
There are four spark plugs on each side of your 1991 Chevrolet engine. The spark plugs will be near the bottom of the engine.
To change the Spark Plugs on a Previa (1991-1996) you have to remove the passenger front seat, lift the carpet and then you will find a cover on the floorplate that has to be removed. Once the floorplate cover is off you will see the engine. There is also a small cover over the spark plugs and wires that has to be removed. The 2.4 liter petrol engine uses small 16mm spark plugs and a small 16mm socket will be needed to replace the plugs.
Assuming it is getting fuel and you have no spark, replace the ignition module.
In the engine... If it is a a straight six. They run in a row. follow the spark plugs wires to them.
You only set the timiming for engines with spark plugs, and diesels don't use spark plugs.
The 1991 Mercury Marquis spark plug gap is .034. Most spark plugs will be pre-gapped by the spark plug manufacturer.
.031 in
0.35
.060"
To change the spark plugs on a 1991 Toyota Camry, first, ensure the engine is cool and disconnect the battery. Remove the spark plug wires by carefully pulling them off the plugs, then use a socket wrench with a spark plug socket to unscrew and remove the old spark plugs. Check the gap on the new plugs and install them by hand to avoid cross-threading, then tighten them with the wrench. Finally, reconnect the spark plug wires and the battery.