Grantkat wrote: ↑09 Jan 2025, 16:26 can it be accessed from underneath?

I don't think so, but it might depend on how the clamp is rotated. You just have to feel around the end of that pipe, and you should feel the clamp. I get to it from up top with a long 1/4" extension.

When you first turn the ignition on to Pos II, can you hear the ETM buzzing? If you can't hear it from the driver's seat you may need someone to do this for you and so you can stand at the front of the car to hear it better. If you don't hear it then there is an issue with it. To control the engine,...

I picked up one of EVAP, smoke testers off Amazon a few years back. They're $60-100. You need to have an pressurized air source, as the "machine" just makes the smoke.

Has come in handy several times, but we own 8 cars, so lost more places to use it.

Sweep test is done in the car. The ETM is controlled by canbus commands from the ECU so everything has to be connected with wiring in good order to work.

Vida talks to the ECU through the OBD port

That leak could very well be the main cause of your issues. Just replace and give it a go. I kind of doubt that the check valve is bad, but you'll find out when you replace the line. Vacuum leaks cause all kinds of fun issues on these cars.
Always start with the easy stuff....

Arggh. I have a 90 degree drill fitting that fits in the chuck, with the bit at right angles to the drill.

Similar to this....

Yeah i have one of those that is probably good for one more removal. I happen to have a wheel off, so here are a couple of pics. The screw does have a beefy head, but a shallow inset. It's recessed about 1". You could try a bolt/screw extractor with a stubby head. Otherwise it might be grinder ...

You might have to go through the air bag for that, Grant

The good news is I have a couple of 99 air bags in stock free to any kat lover

I think you could cut a notch on the side of the steering wheel and gain enough access to grab the head of the screw.

An easy out type tool hammered in to the screw head MIGHT back out that screw. I would try the helical type and grind the end to a close size match before hammering.
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