Want this question answered?
with the info you gave it can be anything prob needs a tune up but just guessing since I have no info
my 1990 300zx is idling rough what could cause this?
A vacuum leak can cause that.
A bad throttle position sensor, on your 1991 Saturn, will cause the engine to run rough when it is idling. The engine will run normally at higher speeds.
If an alternator is going bad it can cause a rough idle in a 1993 Subaru Legacy. Cold temperatures in the winter can also cause a rough idle in the Subaru Legacy.
a rough road can cause the fuel shut off switch to turn off
by making it rough from the wind and water could cause it to flood
The choke mechanism on your 98 Explorer could be sticking. The EGR valve could also not be functioning right. Either of these issues could cause the rough idle problem.
The car will idle rough and hesitate during acceleration.
There are a number of things that can cause an engine to run rough. Plugs may be bad. Plug wires may be bad. If you have sensors, there may be a bad sensor. You could have water in your gas. Could have a burnt valve. There is a number of different things.
Unlikely, Fuel and/or spark are likely culprits.
A timing chain, that needs to be replaced, can cause your engine to run rough and lose power. A broken timing chain can cause significant engine damage.