'84 Toyota Truck 1Z TDI Swap

That seal I linked is inside the vac pump shaft. Super easy to change. Just pull the vac pump out and look inside the hollow shaft of the pump drive. I was very hopeful that it would help my pressure issues, but it never did. I wish you better luck than I.

I assumed it was my intermediate shaft bearings, but I put about 60k miles on the car with it running with basically 0 psi hot idle pressure, and it ran fine. Its still running now as far as I know.

Are you using the Toyota sender and gauge? Because they are notorious for dropping to 0 on the gauge when there is still some pressure there.

I would get a proper gauge and check your hot idle psi if you haven't done already, at least that gives you a number to work with.

I would think you'd have some serious lifter noise close to 0psi

Re. low oil pressure, 1Z TDI Toyota

Aftermarket digital gauge.

I do have some lifter noise. I wish I could detect that everything's ok. I don't think it is.

Seal is here and I'll post an update when I wiggle it out of its tiny little space against the firewall. Sort of a PITA to get at where it's at now.

Thanks guys!

good luck, but dont get your hopes up too high...
Like I said, I just resigned to drive my 1.6 and accept that it had low oil pressure. A couple cross country trips and 100k miles later it still ran totally fine It pissed me off the whole way.

With any suspected oil pressure issue, I trust no digital or factory gauge / light.

Manual pressure test always and then go from there.

Could be a faulty transducer, wiring, gauge etc. plumbing a manual gauge into the oil filter adapter on the 1Z/AHU is a breeze.

Report back with pressure-at-cold-start, hot pressure at idle, hot pressure at 2000 rpm etc.

With the above, we can help - everything else is reading vague tea-leaves.

1Z TDI low oil pressure

"Report back with pressure-at-cold-start, hot pressure at idle, hot pressure at 2000 rpm etc."

Cold Start- 60-68psi (normal is 80 plus)
Hot pressure at idle - 0
Hot pressure at 2000 rpms - 0
The truck will run for about 10 minutes with oil pressure registering 60-68 psi and then will steadily drop to 0 over about 10 minutes regardless of what I do driving-wise.

The o-ring in the bottom of the vacuum pump was indeed quite stretched out, although still pliable. I replaced it and the o-ring midshaft. There is a third o-ring that is ok - it's the one which the "cap" or top of the vacuum pump sits.

(4 pics are in my public photobucket album, linked here: http://s825.photobucket.com/user/truckeebiofuels1/library/?view=recent&page=1

Looking for good free third party image hosts if you've got any suggestions.)

It sucks, but the next thing I would do, with manual readings like that would be to disassemble and inspect. Oil pump 1st, then mains, rods, and intermediate shaft.

With 0 PSI hot There is going to be a gross leak somewhere.

Are any of the mains/rods noisy?

Re. 1Z TDI, low oil pressure

Thanks windex et al.

So, no success. With a new oil pump, oil pan gasket, valve cover gasket, vacuum pump gaskets (bottom of shaft and ~2" dia. o-ring near the pump's seat), inspection of vacuum lines, new oil cooler o-ring and new oil filter flange/stand gasket, the problem remains exactly the same.

Couple of thoughts moving forward. Pull the hose going to the vacuum pump and check for suction. Find a mechanical gauge to replace the digital one I'm currently using and check pressure there.

that's a bummer man, have you checked the intermediate shaft bearings ?

I would definitely confirm your readings with a manual gauge plumbed somewhere, or at least using a different sender before tearing into things any further.

Not 100% clear from your description - does hot oil pressure stay at 0 on the gauge at all rpm or do you get some if you hold the revs higher?

My first autometer oil pressure sender lived a very short life and would give me normal readings at startup, and then drop to zero once it started to warm up. I then read a note on their site recommending remote mounting them in high vibration applications, because this can cause them to fail prematurely. So far so good on my second sender mounted to the fire wall attached to a length of braided hose.

Low Oil Pressure, 1Z TDI

jimbote, I did the intermediate shaft bearings about 20,000 miles ago with tools that jaysinspaceman (RIP) made and shipped to me. That was a learning experience, but I did it carefully and it worked like a charm. So they should be good, unless I did in fact err.

smelly621, that is very encouraging to hear. Thanks for posting your experience. This is indeed a high vibration application. The truck seems to have all the power it's always had. There's no mixing of coolant or oil with each other, and oil's not being burned.

"does hot oil pressure stay at 0 on the gauge at all rpm or do you get some if you hold the revs higher?"
Yes, 0 at all rpms after ~ 10 minutes from cold startup. I do not get a reading above zero holding higher revs.

A manual oil pressure gauge purchase and installation is the next step. Thanks guys!

3rd party image host test



Testing of vgy.me image hosting.

Oct 2017, Tahoe Marina Lodge

The vgy.me works
but the tdi image doesn't work on my end.

1Z TDI, Low Oil Pressure

Thx Zook. What about below?

Pulled the digital gauge and sender. Drove to Reno after researching mechanical gauges. Summit Racing wouldn't warranty my Cyberdyne gauge and said take it up with them (lifetime warr, 6 yr old gauge). Bought AutoMeter mechanical gauge. Installed. Crimped the nylon tubing unrolling it. Excised the crimps and unwound that dang tight roll of tubing with a heat gun. Installed it. Fired it up. Good readings - about 67psi at cold start. Should've been 80psi though. No leaks from engine bay. 1/3 cup of oil on the driver's side floor board.

Do over. Guess I kinked it somewhere when threading down from a-pillar thru firewall and didn't know it and the pressure found the pinhole.

Napa. Oreilly's. New tubing roll. Extremely careful heat gunning of the nylon tubing to get it straight. Disassemble old tubing. Reassemble very carefully, taking care not to twist the tubing as I tightened it, and making sure not to overtighten that delicate brass connector. Done. Ready. Apprehensive...

Drove the company truck 800 miles over two days delivering solar and redwood.

Worked on the AWD rally Passat yesterday Happy New Year!


Fired up the truck up after work tonight. Immediately hit 80 psi. Looking for oil leaks constantly, and letting it warm up for about 15 minutes, I then test drove it about 5 miles. Pressure in the 50s and 60s. By the time I returned home and let is sit at idle, it sat on 23-24psi. (I believe 28psi, or 1.8 bar, is the low end of this oil filter housing-mounted sensor.) So, it seems like success. I will drive it 15 miles to work tomorrow am and see how it goes.

Q: What should be in the nylon tubing. Oil? Air? Both? Right now, it's both - mostly oil.

Yep they work...
The gauge that's on my 4.3 is the same way mostly oil with air bubbles.
Been running it for about 5 years.

what a relief! glad it was the electronic sender and not your motor .... those pressures are normal and my 1z vanagon displays almost identical readings

Oil pressure ok, now brakes are hard and engine does a quick rev

Thanks Zook and jimbote! Oil pressure is normal.

Drove it all over today and instantly noticed the extremely firm brake pedal and a quick high rev at start up. The high rev briefly goes to maybe 2200 rpms, and the brake pedal is dang hard, changing the way I drove/stopped.

***? Booster check valve? Sitting for 2.5 months? Pulling the check valve tonight. I inspected that line during the vacuum pump work and it appears ok.

quick high rev at start is usually a faulty coolant temp sensor that reads extremely low temps ... this causes overfueling and thus the higher than normal rpm

I've also had the quick rev at start happen when the fuel shutoff pin stopped seating all the way for whatever reason.

Congrats on the oil pressure news!!!

vtpsd said:

I've also had the quick rev at start happen when the fuel shutoff pin stopped seating all the way for whatever reason.

Congrats on the oil pressure news!!!

Click to expand...

fuel shutoff pin unseats in the on position and seats in the off position... DBW claimed the oring could work it's way down and interfere with the stop plunger, but this is actually impossible due to the design of the valve

jimbote said:

fuel shutoff pin unseats in the on position and seats in the off position... DBW claimed the oring could work it's way down and interfere with the stop plunger, but this is actually impossible due to the design of the valve

Click to expand...

Yes, I also found that claim to be impossible. I suppose I don't know what exactly failed with my shutoff pin, but that symptom was present on my car every time I started it until I changed the pin out with a spare, problem gone

Fix one thing, then fix another.

Good info, gentlemen. Most welcome.

In reinstalling everything needed for the vacuum pump shaft o-ring, I didn't carefully reassemble the loom harness and the coolant temp sensor wiring. The nearly invisible coolant temp sensor wiring damage threw the code (after jimbote told me, above, what was happening ). Intermittent short to positive. Trying carefully to rearrange the wiring and loosen stress on those tiny wires threw a similar intermittent fuel shutoff solenoid code and another one that i was then too friggin' bummed to address. Dang.

So I am in for some awkward repair splices of at least three wires. This will take a little time and great pain in my back. Oh well. Good lesson in the importance of mindfulness and quality work.

I don't think any of these symptoms shed light on the super hard break pedal, though.

Could it be the brake booster?
Have you tried this...
"
A) With the engine not running, press and depress the brake pedal several times to remove any vacuum from inside the booster.

B) On the last push of the brake pedal, hold moderate pressure on the brake pedal. Don’t push like you are panic stopping, simply hold pressure like you are sitting at a red light.

C) Start the engine and pay attention to what happens to the brake pedal.

D) If the pedal drops slightly, then the booster is working correctly.

E) If the pedal does not move at all, then there is a very good chance the booster is bad."
Just throwing this out there.

1Z TDI wiring harness compatibility

Thanks Zook! I am back on this and will try that.

Pulled the wiring harness. Everything crackled and was incredibly brittle. Its location doesn't work, for accessibility and cooling reasons, so I'm going to relocate it. This will test my tiny-wire splicing abilities

Buying a new harness.

Question - Can I use a '96's harness? I'm just using the end attached to the glow plugs, coolant temp sensor, etc...

96 harness should work fine

Got one coming - thanks k_harley!

8 wire splice

The 8 wire splice worked, allowing successful relocation of the loom from atop the vacuum pump to now front and center at the tip of the brake master cylinder. It only took 6 hours to put everything back together since the Sept? Oct? moment when I began chasing what turned out to be merely an electronic oil pressure gauge sender failure. The harness received lacked the male end of the loom, so, despite confidence that it wouldn't work to reuse my existing brittle end, I did. Each new bend and the jacketing cracked. Each crack got a good electrical tape wrap, and it's pretty shoddy looking. But it worked. I did the best I could with each connection. No codes! Full power!

I installed a new glow plug harness as well, since I destroyed the old one tearing away the loom from its awkward location. The eight wires were:
2 glow plug wires
4 coolant temp sensor wires, which I cannot believe are working and probably won't last long.
2 grounds.



Big enough pic?! I'll post a final pic soon. Great wire nuts, eh? This is soo worth doing. Everything is more accessible now and has better ventilation.

That's going to last about 6 months before it fails. Wire nuts are great for 120V 14ga solid wire, but not 12V stranded. You need to keep water OUT of the wire.

Buy some good heat shrink tubing - the stuff with the glue inside - 3x the price of the regular stuff, but that's all I use as it keeps water out. Do a linesmen splice to make the connection physically strong and then solder it. Then the heat shrink tubing to keep the water out.

1Z Toyota TDI loom relocation

Hasenwerk, no wire nuts were employed in the actual operation of this vehicle This is the way it's been operating for the last two weeks. It's not (too) broken, so I'm not fixing it.

Testing the Waters for Selling Toyota Diesel.

Considering selling the ToyTDI. Change is the only constant. Posting here for feedback from those of you who know about these things. I'm unsure of what to list it for.



1984 Toyota pickup, extra-cab, four wheel drive. Blue. 1997 VW (1Z) TDI 1.9 Diesel. Conversion completed 7 years ago by me. 250,000 miles on truck, ~200,000 miles on engine. ~32,000 miles on the swap. 5-speed manual (original G52 transmission), manual Warn locking hubs. 29-30 mpg consistently at 6000'. Smog exempt. $110/year registration fee. Custom adapter plate more precisely built than ACME or others. Lifetime warrantied Trailgear transmission mount. Recent carrier bearing, and there's a new spare I'll throw in. 4wd works very well. Very smooth shifting.

Just about everything on the truck has been rebuilt or replaced. It drives very nicely, albeit firmly, on 9-way Rancho 9000s, which are 9-way shocks about 3 years old now and have a lot of life left in them. BFG AT 31x10.50s take it about anywhere you want to go.


Pros
Torque. PP520 injector nozzles, Frankenbuilt chip tune, 2.5" exhaust with resonator only, K&N cone intake filter, aftermarket intercooler. Estimated 130hp and 250 ft lbs tq.

Healthy fuel injection pump.
Timing belt water pump etc. good for at least another 50,000 miles.
Modern JVC stereo with CD/USB/Aux input and Kicker 6x9s.
Heater works, and heater core was replaced with new 7-9 years ago.
Rear disc brake conversion using Cadillac rotors and Sky manufacturing adapter kit and Summit racing proportioning valve.
Newer seats from a mid-90's truck. Small tear now on driver's side seat.
Sliding rear window.
Campershell (aluminum) with sliding window and working shocks.
Lumber rack that works well and looks good with removable rear crossbar. (Shell and camper don't mount together but could be modified to do so.)
Steel bumper with trailer hitch and working pigtail.
All lights and switches work.
Boost, pyro, and oil temp gauges.
Peugeot fuel filter housing featuring manual priming button/valve. Fleetguard fuel filter with (unconnected) filter wear indicator and heating element.
Viton fuel lines only.

3-4 year old very nice aluminum radiator.

Bombproof custom motor mounts.
2 year old tie rod ends.



Cons
No ebrake. Have mechanically controlled line lock, just haven't needed to install it.
No horn. Electronics at steering wheel need to be replaced. Horn is new and installed, but only later did I discover why it wasn't working.
Typical rear fender rust spots.
No ABS.
No airbags.

Paint fade on hood. Only rear tailgate and qtr panel have very small dents.
No AC. Heater switch needs to be left on all the time for coolant flow. Fans, defrost, vents, etc work fine.

No coolant temp gauge. I know the truck well enough to know if it's hot or going to overheat (never has even come close). I have VAGCOM and use it if needed to monitor temp.



The only thing this truck needs right now is to have the rear main seal replaced, as it leaks oil. I have these materials on hand and plan on doing it within the next couple of months, preferably sooner rather than later. Some extra parts come with it, as do all of my records and receipts since taking ownership in early 2009.



Located in Truckee, CA.