Any credibility I had as a home mechanic is shot. It was the p/s fluid level. Found a slow line leak from a loose philips screw clamp. I'd emptied the last of a can a few months back (before rebuilding the head/replacing the headgasket). Not sure the last of the can made it up to the MIN-line on dip stick. Anyway, even though there is a lot still of fluid in the tank, the level was below the dip stick MIN.

DDH, thanks for the info on the ps pump. As this has been going on for a while, I may need a pump someday. Do you know if the 300TE gasser waggons have the same ps pump? What is the SLS?
And yes to the symptoms, it was not "Brrrrt", it was 2-3/sec. I felt it mostly in the wheel, and passengers could feel it. It pulsed at slower speeds, close to idle or coasting into a turn at low RPMs, worse when not warmed up. I did feel it in the brake pedal, so I tried not using the brake and coasting, or accelerating into turns. Pulse was mostly notable on Right turns which is the symptom that indicated the "commom 124 worn ABS wire problem". And yesterday when fluid was lowest, it also pulsed going straight. This was less than a week after I replaced the 2nd pair of ABS sensors. You were right to diagnose the 2-3/sec vs the brrrrt.

Aquaticedge, Thanks for the heads up on the filter. The ps pump looks awfully clean on this engine, and I didn't clean it or replace it, so I'm guessing PO did (the leaky line culprit). I think I'll just run it a while, and see how it feels. And i'll put the filter/fluid change on a future (deferred) maintenance list

1stnc, I feel for you. The length of you diagnosis is painfully reminiscent of what I went through to diagnose my headgasket problem. Congratulations of finding you need new glow plugs. That may fix a lot of your start problem. Good luck with the compression test. FYI Be carefully with the socket wrench removing and reinstalling the injectors. It's easy to bend the small ports on the sides of the injectors. They can get bent in too close to the injector for remounting the return line (some of mine bent in, and I prayerfully pried them back out.) And be sure to turn the engine over enough times to get a good reading.

You'll have a chance to inspect, clean, air-out, each injector for crapage. You said you replaced the woven fuel lines on the injector ports, blow them out onto a kleenex to see if any particles are in the new lines. And you could remove the hard lines from the IP and blow those lines out, too. Who knows what you'll find in them? How do your filters look now? Any rust particles? Any particulate in the bottom of your Diesel Kleen bottle?

I'm inclined to go with others on your thread who point at your really dirty fuel That is a problem. The fuel lines have to run clean. Emptying the tank, cleaning the fuel system, replacling the new filters again, and new glow plugs could do it for you. (k.i.s.s.)

I don't remember seeing that you looked into your injector pump for rust particles, just that you removed some hard lines, and wanted to replace the IP. On my previous 87 wagon I'd replaced just my pump's rubber O-rings (2 x 6), and cleaned the pump following a DIY on this site. I have the splined socket tool if you need to borrow one. But I think you'll want to get rid of the fuel you have first. Especially if your tank is the source of the rust particles, and the particles are getting through your filters, it may be the belly of the beast you're fighting. Some guys posted about biodiesel being hard on the rubber. I only ran 2 tanks of 1/2 bio and 1/2 dino, and I had to rebuild my ip because it started leaking (worse) from O-ring deterioration. Was the O-ring deterioration caused by the bio? Lots of people say it is. And lots of those same folks are saying bio "cleanses" the rust from your tank. I didn't notice any rust problems from my brief flirt with bio, just fuel leakage.

I'd do all I can to be sure the fuel lines are clear before "fixing" the cat. And I'm speaking as one who has done the cat, since I had the exhaust off to do the head. I didn't notice a change in exhaust improvement. Working around under there is a PITA. You may want to leave the ex-manifold plug off for a while to simulate a fixed cat.

Hey wait, don't pay attention to any of this. I just remembered: I don't have any mechanical cred. So it probably is the cat!

Good Luck.