The red lebarron misses again

92 lebarron conv.
4 cyld. non turbo
new cap, rotor, and plugs
misses on 3 and 4. when pull plug wires engine doesn’t change. when pull 1 or 2 it dies. when put in gear it chugs and dies.

@techniptionfit

So cylinder 3 and 4 are not contributing at all

Here’s what I would do

Compression check
Make sure all 4 injectors are at least clicking (if it’s EFI)

There’s no way the wires are misrouted or mixed up?

Important question

Was it running on all 4 before the ignition tune up?

tbi so that’s not it. i took pictures before hand and the numbers on the cap match the appropriate picture so i dont think they are misrouted. i swapped plug wires (completely) and the problem did not follow the wire. it was not running on all 4 when this all started. and of course its stuck at my dads work.

thanks for the added info

There’s a lot of things that could cause this. First thing first though. Are you getting a good visible spark on 3 & 4 that match the quality of the spark on 1 and 2? Harbor Freight has an inexpensive gadget that makes it easy to check for spark.

The spark will jump out of the boot if held close to metal on 1 and 2 but 3 and 4 not as often

but that could be a miss observation based on me looking for problems

@techniptionfit

If you want to check spark, this is safer and more accurate. If you use it, the spark should be bright blue.

http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Electronic-Ignition-Spark-Tester/_/R-BK_7002456_0361146064

Another suggestion

Take off the distributor cap

Do you feel any obvious/excessive play in the distributor shaft?

A few interesting things to think about

3 and 4 are missing
Firing order 1-3-4-2
3 and 4 cylinders are physically next to each other . . . blown head gasket?
Worn distributor gear?
Worn distributor shaft?

You said you had TBI . . . 1 or 2 central injectors?

compression cheeck
1=120
2=120
3=110 ish
4=97 ish

@techniptionfit

That’s actually on the low side . . . very low, in fact

Ideally, the engine would be warmed up before performing the compression test . . .

But that wouldn’t make a night and day difference as far as those numbers go

Some engines would be misfiring and/or have difficulty starting with that kind of compression

Remove the spark plugs
Squirt a shot or two of oil into each hole and do a wet compression test
Did the numbers go up dramatically?

Do you have adjustable valves?

i will do this tomorrow