924Board.org

[autobahnkid]

The beast is out of the garage and again in my tender loving hands.
After sitting unused in the garage for over a year.
She is not happy at all, acting like the abandoned scorned woman she is!

At first she would not start at all.
Replaced battery new, cleaned plugs, replaced cracked distributor rotor.
She fired up and immediately shut off .repeat.

Checked coil, wires, loosened fuel connectors at cis, fuel comes out. jumped relay.
Restarted, lasted longer running, shut down.

Ok out came the Haynes and reread every thread on cold start.
Pulled CSV ,it fires.
tested 12V at connector +.
Pulled AAV, found gummed up, placed in freezer, stuck.
Cleaned AAV with Maf cleaner. All kinds of goo came out. Refroze. It now moves from 5/6 open when cold to 9/10 closed when warm.
Reeinstalled.

Pulled connectors to WUR, AAV, CSV cleaned with MAF cleaner. reconnected.

Rigged CSV with push starter switch. Figured TTS is not grounding CSV. I can put my hand on it but have been unable to pull the connector to it.

Engine fired and remained on so long as I pulsed CSV. Then shut down. No response to throttle pedal.

After several tries the car now responds to throttle and runs very rough. Some injectors might be gummed up.
Added can of seafoam to gas tank, fuel had been preserved with stabill + new fuel added recently.
It will run indefinitly so long as pedal is depressed. It will not idle. Very rough below 2000rpm, then shuts down . I guess CIS is now unstuck.

WUR resistance checks ok. There is no leaks from fuel pressure regulator. I have not removed bottom screw.

What should I do next?
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1980 924 N/A "the beast'

[ideola]

Proper test of the CIS system:
http://www.924board.org/viewtopic.php?t=35734
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erstwhile owner of just about every 924 variant ever made

[autobahnkid]

Frustrated
I will keep checking the fuel system before even considering touching the K-jectronic.

I re-measured the resistance across the pins at the WUR and got 29 Ohms.
resistance at AAV is 65 Ohms.

Decided to pull the WUR. I t is now out of the car. Bottom hex 5mm bolt was a b**th to get to. Used the hollow of a tire iron to turn the hex key. also a locking plier on the short end.
The banjo bolts were no piece of pie either, off with 14mm open wrench.
The copper washers fell onto the belly of the beast. Did get them back.
Not a drop of fuel came out. vapors only.

I am not looking forward putting this bolt back in.
For access cleared the coil and the black vacuum hose from the rear of the throttle body.


I
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1980 924 N/A "the beast'

[Fasteddie313]

I would..

Reinstall the fuel line from the fuel distributor to the WUR with a CIS tester inline if you have one, put it in a bucket to catch the fuel that comes out of it..

Pull the injectors, keep them on the lines, and set them into individual bottles..

Gain access to the air metering plate on the fuel distributor..

Jump the fuel pumps circuit so they run..

Then go under the hood and check out what gas you're getting from where, the wur should be letting fuel out, play with the metering plate and see what you get out of the injectors, they should spray nice cone patterns and fill your 4 bottles evenly.. 4 identical pop bottles would be good to compare their levels.

Spray a bunch of fuel, it may clear itself out if it isn't great from the start.

Confirm operation of both fuel pumps if your not getting anything or not much...

If you don't get fuel through the WUR try it without the WUR to see if you get fuel to the WUR from the distributor..

This is a fun job, the injector squeal sounds really cool, and you really get a feel for how the system works..

BTW
"I will keep checking the fuel system before even considering touching the K-jectronic."
The WUR is a key component of the K-Jet system, pretty much all of the fuel system is "the K-jectronic"
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80 Turbo - Slightly Modified

[autobahnkid]

Fasteddie thank you for coming to the rescue.

I will have my CIS tester in next week, so I can test what I can without until then.
On inspection the filter on the inlet (top) side of the WUR is clogged, I have sprayed cleaner and canned compressed air to clean a bit. Partially unclogged now.
There is no filter on the outlet side.

Popped the WUR open, surprisingly simple inside, very clean. The rubber seal in very good shape.
The filter however is not reachable without further disassembly. I would have to remove the bimetallic piece and heater, to reach the circular plate underneath (the actual regulator?) and unscrew the four bolts of the round cover.
Not sure I want to mess with this any further.

Still stumped by the low resistance value 29Ohms vs 35-45Ohms good range.It would seem to point to a bad heater. I wonder if this is available at a parts store for electronics? Could it be these things can be repaired?

I will pull the injectors, praying the lines don't break.
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1980 924 N/A "the beast'

[autobahnkid]

Thanks Ideola.

Also got under the car to check if there is any fuel coming out of the screw of the fuel accumulator. Totally dry.
I may still remove it for further check. The screw now rotates in place but will not tighten.
Im going to pull down one of my old Agatha Christie novels to read as I go along.
Better reading than Haynes.
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1980 924 N/A "the beast'

[Fasteddie313]

"Not sure I want to mess with this any further."
Nor am I..

"I wonder if this is available at a parts store for electronics?"
I doubt it

"Could it be these things can be repaired?"
Yes, I see many people here recommend this guy
http://www.specialtauto.com/porsche-parts/index.html

I would test the WUR with your CIS testor and everything else before sending it out. Pumps, injector spray, system pressure, control pressure, frequency valve (if you have one, what is the car exactly?).

The bottom of the accumulator should be bone dry, thats good..
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80 Turbo - Slightly Modified

[autobahnkid]

Today I advance in the exploration of the fuel system.
Opened the Banjo bolt on the return line at the front of the fuel regulator17mm, fuel came rushing out. Blew compressed air and got a shower shot back at my face. I forgot to open the gas cap.
Left the cap just barely placed on the opening, blew air and the cap was forced out. Concluded the return line is not clogged.
Also noticed that the outer shell of the line is badly cracked close to the fuel regulator.
Should this line be replaced? What type of fuel line is it?

Jumped the fuel pump relay and observed fuel come out of the WUR intake line.

Removed coil and all vacuum hoses at the rear, cleaned all grounds and connectors. I can now touch the TTV plug but have no leverage to remove it..
Any suggestions as to angle of attack?

Also removed again the AAV valve, it was almost fully closed at ambient temp of 85F. Not yet convinced this is the correct behavior. It is back in the freezer, will retest.

Removed the intake three piece snorkel from the air regulator to the throttle body. Removed vacuum hoses attached to them.

Cleaned the butterflies and body of throttle. cleaned the connector to the switches under TB, one was very sulfated (green).

Removed and cleaned connectors to the solenoid under the fuel distributor and the EGR valve(??).

Loosened the retainer brackets for the fuel lines.

Connected the WUR's intake line, installed pressure tester to outlet side of WUR. Jumped fuel pump. Fuel came rushing out of the connector to the outlet side, wrong fitting.
At least we now know fuel circulates through the WUR. Reattached line to WUR outlet.
Pulled injectors, placed into receptacles, jumped fuel pump. Lifted metering disc, all four injectors fired a clean cone into the containers. All the containers had about the same amount of fuel.
Replaced baked O-rings with new, Monday will replace the bases and will reinstall the injectors.

Concluded fuel distributor is not stuck and working reasonably well.
So fault might still be a bad WUR, vacuum leak, insufficient spark? Monday will use a new coil.
Still to be determined what are the pressures on the system.

I am beginning to get very close to the heart of the Beast. IT was a good fun day.
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1980 924 N/A "the beast'

[autobahnkid]

Well guys, ended up removing replacing and reinstalling all of the vacuum hoses. Including replacing the last of the original cotton wrapped hoses that go to and from the charcoal canister. They were dry rotted.

Loosened and lifted the air flow valve unit including the regulator. Replaced the O-rings on the AC compressor while having access. Replaced the dryer. She hold vacuum. Compressor clutch activates with 12V on positive terminal.

Smoked the vacuum system and found a leak at the two horned temp valve next to the firewall. The rubber hoses were to thick to remain both in place.
So I carved part of the outer edge so both would fit. Still have a small leak but nothing like what was there before.

Reinstalled WUR AAV and CSV and their fuel lines.

Turned ignition and voila, started like a top.

CIs tester is finally in. I will use it to check the system. Now on to the smaller pending items, and deciding what gas to charge the A/C.

Thank you all.
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1980 924 N/A "the beast'

[Rasta Monsta]