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