Hi guys,   I just bought a very nice 91 Sidekick JLX with 105,000 original kms (65,000 miles) on it.

I have noticed when driving it that it kind of "jerks and bucks" at a steady engine speed around town. it's not horrible, but it is very noticable.  I have changed the plugs and air filter without any luck.   Anyone know what could be causing this problem?  It starts and runs perfect with the exception of this.  

Any help would be greatly appreciated.  

idle problems on my buddys care were fixed with a throttlebody swap, so try the throttle position sensor & wires.

MAP too can cause funny stuff.
The Puter gets a major input from the
MAP, but it will run without the
TPS.

I had a similar probelm on my 90 Trooper 2.6. It turned out to be the O2 sensor, after I replaced it it ran great again.  Hope this helps a little  Dave

The O2 helps adjust the mix and keep it lean.
But it will run without it, mileage is real bad tho.

when the 02 sensor went on mine all it did was mess up the idle speed
once changed all has been great since
if you cannot find the problem from advice given here then get it to a dealer and plug it into the analyser
tonka-toy

when the 02 sensor went on mine all it did was mess up the idle speed
once changed all has been great since
if you cannot find the problem from advice given here then get it to a dealer and plug it into the analyser
tonka-toy

Good idea.  When all else fails, plug the darn thing in.

Modern vehicles are nice to work in in this regard and crappy at the same time because you need all of the specialized test equipment.