Running on 4 Cylinders

[zira]

Hello all:

First time poster.. Extensive forum reader (and searcher)

I have a 1992 LS400-It's been real good to me over the last 3 years..:hitit:

Mom was driving - said something wrong with the car. It's only running on 4 Cyl - I immediately think ignition coil. Changed the one on the top of the engine (easy access!) and no improvement. I checked the driver side plugs - 1 and 7 not firing. Is this going to be as simple as changing the other ignition coil? If so how to I get to it? And since the original coil (from top that I changed) was fine should I only change one, or is it better to change both?

Thank you!


z :burnout:

 

[mshawari1]

Try to replace the second one by the old replaced one.. its above the A/C compressor. Otherwise you have to check the rotator cap and the wires …etc..​

 

[Lextreme II]

U can test the coil also before changing. Check the OHM.

 

[zira]

Great - Thanks!

 

[Lextreme II]

There are multiple articles on testing the coil ohm in this site..

 

[Zuffen]

If swapping the coil dosen't help and the cap and rotor look fine check the HT lead from the coil to the distributor.

If that fails try swapping the cables between the igniters as one may have died. This would make the opposite cylinders stop firing and bring the dead one's to life. Assuming the plugs aren't too fouled.

When all that fails I'd check the igniter wiring for continuity.

 

[zira]

If swapping the coil dosen't help and the cap and rotor look fine check the HT lead from the coil to the distributor.

If that fails try swapping the cables between the igniters as one may have died. This would make the opposite cylinders stop firing and bring the dead one's to life. Assuming the plugs aren't too fouled.

When all that fails I'd check the igniter wiring for continuity.

Now that is fantastic help-

I very much appreciate it!

I'll be back with updates..

Thank youi!