I'm thinking you're in need of a basic 'stage 0' tune-up before you spend any more money on expensive stuff.

I'm assuming this car has the 5 cylinder engine, 2.4 turbo, with ETM.

Whenever I hear stalling and idle issues I think vac lines. If you're mechanically savvy as you say, this is no big deal, but will take some time and patience. Pull out all your intake/intercooler ducting and airbox and start replacing vac and PCV lines. Do one at a time so you don't forget how they all fit together. Don't bother inspecting, just buy a whole bunch of new line in different sizes and replace everything. Get a 'pliers' type cutter so you don't kill yourself trying to cut the lines with a knife.

Also, split the old line up one side and use it as a heat shield on your new lines where they're exposed to heat from the turbo or laying against the block, etc.

You can make an 'elbow' replacement from straight line by doing a loop.

There is a pesky one (an elbow) for the PCV system on the pass side of the intake that is known to cause problems because it's not easily discovered.

While you're doing this clean out your IAC and the PTC nipple on the intake - you should be able to see/blow right through it. Take a minute to take a toothbrush and some TB cleaner to your throttle body as well.

I heard a good tip the other day about cleaning the IAC : clean it with TB cleaner to dissolve any oil/carbon/dirt/etc, but then rinse it out with WD-40 to prevent water from freezing inside there and gumming things up. I have had a few of these things 'freeze' up after ingesting moist air from car washes etc (admittedly on the old redblocks though, not the whiteblocks).

Also, how old are you ignition components? plugs, wires, dist?
How about your O2 sensors. If the front one is more than ~50k miles old I'd replace it just to get it out of the picture. Ditto for the rear one, but I'd trust that one to about 100k miles.

Idle on my car is more like 850 (my OBDII always says 840).

It would be worthwhile to buy some electrical contact cleaner and some dielectric grease and treat your sensor connectors to a little TLC as well.

I'd give the old girl the 'water torture' and seafoam treatment. Do a search on the RWD forum for info on how to do this. Then an 'Italian Tune-up' for good measure. Make sure the car is good and hot before you start really racing the engine in low gears (fresh oil wouldn't hurt).

An AutoRX treatment would not hurt either.



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1998 V70 AWD Turbo 195k+