Re: '89 CRX HF + D15Z1 troubleshooting...
 

https://en.wikipedia.org/wiki/Calcium_Lime_Rust
Mostly harmless...I bet it's fine for aluminum.

Re: '89 CRX HF + D15Z1 troubleshooting...
 

Well I'd definitely not call it "mostly harmless" since it is capable of seriously hurting you if you don't wear gloves while using it.

Re: '89 CRX HF + D15Z1 troubleshooting...
 

Eh, the EGR's bolts are destroyed...they won't budge & nothing will grip them beyond an infant's strength to turn them. I PB Blastered them overnight but they are too far gone. In other news the IACV clicks fine w/ supplied 12v & back when disconnected. My thought would be to drill/grind the nuts off if I have to but the one closer to the fuel rail is a tight space for sure. I'd have to drill the bolts out completely and use a hex bolt/new nut combo to tighten her back down. Never used CLR for car-related stuff.....

Re: '89 CRX HF + D15Z1 troubleshooting...
 

As a last resort, I sometimes use a hammer and long thin chisel on rounded off nuts to spin them loose.

The chisel needs only to be moderately sharp and you need to angle the chisel as much as possible to get it to rotate but not so much that you end up carving off chunks of the nut.

If you have a welder and enough clearance, you can sometimes place a large nut over the rounded nut and weld the two together.

Re: '89 CRX HF + D15Z1 troubleshooting...
 

I'll try the chisel method, I don't have a welder handy, it would come in handy on days like today.

Re: '89 CRX HF + D15Z1 troubleshooting...
 

***update***

Never got the EGR off and the nuts are now officially mutilated. Once I reset the idle w/ a bias towards high (we're talking 50-75 RPM max) she cleared up most of her gremlins that are idle related, still have noticeable rev in neutral overrun. I have to focus on house related crap now so I may lay off smoothing her out til I get some extended top hats to lessen the Eibach Sportline thunk. Thanks everyone, Mak

Re: '89 CRX HF + D15Z1 troubleshooting...
 

Lots of info- thanks a lot all! :)

BTW "The PCV valve is new, and with the straight-through VX design I don't see how it can fail, it's just a hollow elbow."

Maybe important for some - the elbow is not the PCV. The PCV is located under intake manifold (hard to reach but possible when you put your whole arm between firewall and intake manifold).

Cheers!

Re: '89 CRX HF + D15Z1 troubleshooting...
 

one of these days I'll get a video of the "fickle Shift light". Below 2k and usually in 3rd gear up a decent hill, the shift light will flicker like an old fluorescent bulb until it builds enough RPM's and decides to stay on solid green. Still has neutral rev overrun, but the original cruise/buck issue is much smaller at the moment.

Re: '89 CRX HF + D15Z1 troubleshooting...
 

I should have done this one post #1...better late than...

This is "cruise/buck".
https://youtu.be/rLj6wmSDDRc

This is "fickle shift light".
https://youtu.be/EJCU98uB-ik

I believe these problems are related. Any suggestions?

Thanks,
Mak

P.S. Is there a way to embed these videos?

Re: '89 CRX HF + D15Z1 troubleshooting...
 

I've created a new thread just for videos, as this thread is too long for some attention spans...:)