I haven't done much work on the Suburban since we bought it (with 21k miles on the odometer), and now with 90k miles on it, the 'burban was due for some servicing. I installed a K&N air filter at around 30k miles, so it was time to clean and re-charge it. This was a fairly trivial task, once I purchased the recharge kit from the auto parts store.
Next, I decided to change the spark plugs. Most new cars don't need the plugs swapped out until about 100k miles, but since I was experiencing the idling problem, I thought it would be a good first stab at the problem. One thing nice about the Suburban is that the engine is fairly accessible compared to many other cars. I bought 8 new AC Delco Iridium plugs, and took out the old plugs and replaced them with the new ones, only losing around 5 pouds of weight due to sweat during the process.
Next up was a new fuel filter. I have replaced it once before on the Suburban, but it is always fun trying to squirm under the beast and disconnect fuel lines, etc. About an hour after I started and many expletives later, the new fuel filter was in and I could call it a day after I started her back up and gave her a test drive.
Unfortunately, all the work I completed had no effect on the low idle / stalling problem - argh! I was done working on the car for the day.
On Sunday, I decided to research the problem on the internet, and found that this is a somewhat common problem for the Chevy Vortec engines. The most common advice I found was to clean out the throttle body, and this would usually take care of the problem. The procedure couldn't have been easier. Disconnecting the air intake from the throttle body allowed me to take a rag with a bit of acetone on it, and clean some built up carbon deposits around and on the throttle plate. The job (which would have run me in the neighborhood of $50 - $150 at the dealer) took 15 minutes and cost maybe $0.25 in acetone, and the problem was completely solved!
