Why A Rough Idle After Tune-Up?
 

I changed out my spark plugs, replaced my fuel filter and changed the oil and oil filter and after start up, it idles a bit rough. Its the 2.4, 1973.5T CIS engine. I went back to check my spark plug connectors, make sure I did not bump any vacuum, gas or electrical lines, and yet its till on the rough side. On the road it runs like a bat outta hell in all gears throughout the rpm ranges, but its very peculiar why this happened.

Can new spark plugs cause an issue? Richen up the mixture?

Any advice is always appreciated from you folks.

Thanks
Bob

73.5T - CIS

Although you didn't mention it, I assume you gapped your plugs correctly...

I used the right plugs and gapped correctly. The idle is a slight intermittent miss, that although is not very pronounced, was not present before. Its a mystery to me.


Bob

Assuming your ignition cables are old stock Beru, disturbing them with a tune up might be enough to cause them to fail.

Joe

Assuming you used the same/ correct plugs.
Did you check your rotor, cap,timing, and dwell?
Maybe your dwell & timing are off but you didn't notice it before.

If you have a pop off valve you might make sure it's seated.

Joe