New to the area, 100 series giving me grief

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Aug 15, 2017
Reno, NV
Hey all. We just moved to Medford. We have a 1999 100 series that has a few issues suddenly. I'm not sure if some or all of them are related or not. Hoping someone can help point me in the right direction or maybe to the right local mechanic.

We moved from northern nevada, altitude about 4500ft. Driving was almost 50/50 highway/city. Mileage was about 14 MPG average. Fuel was premium with 10% ethanol, as far as I know, primarily from Costco.

Here our driving is almost all city with a lot of idling. When I go to the store, for example, my wife wants to get out of the house, but not go in, due to covid-19, so she sits in the idling truck while I go shopping. Time-wise, my trips are about 50/50 city driving and idling. I know this is bad for it, so I'm trying to minimize this going forward. Gas is usually premium from Costco.

Recently I have done or had the following done (parts from Cruiser Outfitters unless noted):
-front wheel bearings, both sides
-upper and lower ball joints, both sides
-steering rack (reman from Roseville toyota)
-replaced cooling hose that goes to base of oil filter, like 4in long with a bend in the middle. Couldn't get the molded hose, was told to use bulk hose.
-drained and refilled all three diffs with Mobil 1 synthetic 75w-90
-oil change
-brake system flush and fill
-passenger front axle (not sure manufacturer, done by Dave's import)
-spark plugs
-2 of the coils

Now the problems:
-very low gas mileage, like 8-9 mpg
-ABS light on. Previous mechanic said it was driver front sensor, but this lit after he did the steering rack, wheel bearings and ball joints
-occasional clicking, I think from the drivers front, but not completely sure
- when it had been running for a while, probably 30+minutes, idles inconsistently. Based on the tach, normally idles like 700. When the issue occurs, idle will start to go down to about 500 over a second or two. Engine will almost die, then rev to about 1000 for a few seconds then back to normal. It will then idle normal, sometimes for 30 seconds, sometimes for a couple minutes, then it will drop and rise again. Sometimes it does die. It starts back up everytime.
-the clunk when shifting from park to drive, I need to lube the drive shafts, but don't really have everything I need to do it right now.

I'll have to add more later, my phone is dying. Thanks in advance for looking.
Depending on how long the vehicle is idling the mpg may be right.
For example. Full hwy tank in my truck is roughly 15. Last tank offroad was like 6-8 i think.

Ime a good scan tool that will read abs codes and display wss is super helpful /necessary when diaging abs stuff.

Your idle issue could really be a ton of things. Id look at the MAF and IAC first. It may be worthwhile to clean your MAF, it may also help mpg. If you are using an oiled air fikter, throw ut out and use something else.

For a reputable Toyota mechanic i recommend Grants Pass Toyota
My idle wasn't as rough as you say, but I changed my PCV valve and grommet which put the truck back to a OEM smooth idle. I had previously replaced all coils with OEM ones which helped restore some power and smoothness but the PCV Valve completed it. Old was upon inspection wasn't acting as it should.
14 mpg is high for an awd v8 unless its mostly hwy miles. Had an 05 tundra with the 4.7 v8 and real 2wd in the transfer case and only saw 16mpg at most with stock tires and only hwy miles. After a little lift and tires and in town driving I was down to 12mpg with no idling. I tow constantly and with that it was more like 10ish. 8-9 mpg with idling isn't crazy. Don't idle would help save you money but you didn't buy an awd v8 landcruiser to save money on gas did you?! Don't believe anything the previous owner said. Test drove a gx470 one time and the guy was like "its great on gas!" Once I scrolled through the menus I found it was 8.9 mpg. Unless you hand calculate it every time dont believe it.
Just got back with my 5.7 tundra towing to montana with a 22' trailer and saw 6-9mpg hand calculated with 0 idling.
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