Greetings. I just purchased a 2002 SL2 DOHC with 158,000 miles. Had the car inspected and most everything checks out. Mechanic said the front struts need to be replaced, the belt tensioner needs to be replaced, and idle speed is too high. He didn't diagnose further but I did some research and, based on the symptoms, I'm guessing it's the Throttle Position Sensor. Other than that, there were no other issues found. There are no maintenance records whatsoever for this car so my questions for the forum are this:

1) With 158k miles I assume most components are nearing the end of the expected lifespan. Are there particular components that could fail suddenly leaving me stranded?

2) Should I take a proactive approach and replace those components now or would you recommend that I just wait until they fail?

3) Given the above, are there particular repairs that I should piggyback together? For example, I'm already considering replacing the TPS so I might as well remove the entire throttle body and follow the cleaning procedure described in other posts. Are there other repairs that make sense to group together and perform all at the same time?

As a new Saturn owner, I REALLY appreciate your advice. Thanks!

 

how high is idle?

 

If it's not broken or worn out, why replace it? I'm a cheap bastard and don't replace things unless they obviously need it.

 

"Normal" idle is 800 - 1000 rpm. After the car is warmed up I've noticed that if I shift into neutral at a stop light the the rpms will jump up to 1500. If I put it back into drive the rpms drop back around 1000. If I turn the key off then back on the idle will return to normal.

 

Alot of parts will give some signs that they're ready to be replaced. However, I'm concerned about those components that would suddenly fail leaving me stranded.

 

Usually the ones that may suddenly fail and leave you stranded are not the ones you can readily see, but internal ones, such as timing chaing, valve springs, connecting rods, bearings etc. You can't be paranoid and own a Saturn. They're good cars when regularly maintained.

 

If you don't have a check engine light, don't start replacing parts. Replacing some of these parts can cause more issues so if it ain't broke, don't fix it. The Saturn struts are very good so I would not change those either. My 2002 has 267k miles, I live in the country so the roads have plenty of potholes and my struts are just fine.

I didn't replace the original accessory belt until the car had 232k miles on it. When I had to replace the water pump last year, I found a little play in the idler pulley, but the tensioner was perfectly fine, so I replaced only the idler pulley.

The throttle position sensor is not bad, when it goes bad, its a one trip DTC and puts you in limp mode. Your high idle is due to something else, often a vacuum leak. If you had an SL1, I say its the intake manifold gasket but I don't think the SL2 shares that issue. Could also be the egr valve or the ECTS.

Remove the intake duct to the throttle body and open the throttle all the way. If the backside of the throttle plate is gunked up, then remove the throttle body and clean it, but have a new gasket at the ready first. Also remove the EGR valve and do a preemptive cleaning of that, but only if the throttle body needs cleaning.

Other than that, just keep good oil in it and it should serve you well. You might also want to drain the transmission fluid and replace the filter. Do not flush. Use the newer Dexron VI instead of Dex III. Check the coolant too, replace if cloudy, again do not flush, just drain the engine and the block and refill with either a long life universal antifreeze or Dexcool, mixed ahead of time with either 50% distilled water or a 2:1 mix of antifreeze and distilled water. I like the 2:1 myself.

 

Thank for the great info. Much appreciated.