Help with lambda/freq valve test please

[Bob Kontak]

Originally Posted by boyt911sc

BTW, anyone suggesting to use starting fluid or carb cleaner to locate this illusive air leak is not a CIS guy.

Why don't you expand on this, Tony. Maybe I should just stick to working on 1994 F150's? I will say I could have had both these guys rolling in style by now if they were near. There is a lot to the CIS system and many times a down to earth explanation or trouble shooting exercise is more than sufficient

I promote using carb cleaner to find leaks. Is that what constitutes not being a CIS guy? Is that all it is? You have to have a rubber glove to put over the TB or you are grasping at straws?

Also, the car is 30+ years old and you are expecting the factory plug to still be in the 3MM hole and untouched?

Seriously. Is that what you think is happening as a rule? No one touches the 3mm screw?

Explain.

[gazzerr]

Hi Tony,

I haven't and I will not touch the screw until I can completely verify that I've got no air leaks and fuel pressures are good. I've been fixing obvious visual (looking for cracks and holes) air leaks and faults for a while now specifically:

1. Numerous cracked and perished vacuum hoses -> replaced
2. CIS boot had huge cracks in it - it's a wonder it ran at all - it would hunt, drop rpm and stall at stop signs -> replaced
3. Oil tank level gauge sensor cork seal was in pieces -> replaced, car would now drop rpm when oil tank cap was removed
4. Non functioning O2 sensor -> replaced, engine exhaust much better without rich smell
5. Replaced out of spec O2 relay with proper spec relay that includes the correct diode -> replaced
6. Repaired and reconnected O2 mileage counter wiring. I couldn't find an actual electrical connection between the counter and the OXS box but I figured it couldn't hurt to fix it
7. I still have leaky injector seals - next project (fails the carb cleaner test - but this a bad test as you advise, need pressure test)
8. WUR only registers 10.1 ohms so it starts easy with about 2 to 3 secs of cranking but when cold idles low and is grumpy until it's warm, suspect out of spec WUR - confirm with fuel pressure test. I now have gauges to test with. When warm it starts up right away when you turn the key.
9. AAR is open when cold and appears to close when warm - have not checked resistance on it.
10. Need to check ignition timing.

When I remove the oil filler cap I get a good drop in engine rpm and the engine actually runs a little rough so I think all in all any nagging air leaks should be minimal.

The shear off plug for the mixture in the FD has been drilled out so how it's been adjusted is anyone's guess. The Mighty Actron was an attempt by me at trying to find an indication of what it's been set at. Seems like the newer batch of Actron boxes are not compatible with the electrical signal from the test port (Bob's experimenting with his Actron box).

Once the car is warm it runs great with good smooth power and response.

So that's where I'm currently at.

G.

[aprilkontak]

Originally Posted by gazzerr

(Bob's experimenting with his Actron box)

Probably eight years old. Does new mean different? Don't need to experiment, it works.
I am speaking for my Dad. He is on the ventilator after reading Tony's post.

[gazzerr]

aprilkontak -> I bought mine from Sears about 6 months ago. Same model number. Seems like newer production boxes can't handle the square wave signal from the test port. Numerous complaints on this forum.

[boyt911sc]

Gazzerr,

I did not say that using volatile spray on suspected leak sources is bad. Someone would get upset about this. It is not an effective and efficient method for finding hard to find sources of air leaks in a CIS engine compared to pressure test like a smoke machine or pressurized air or immersion technique.





April,

I met your father a few years ago and he drove a long distance for lunch some where in Ohio. We had a good time. We communicated via email and even spoke over the phone a few times. There is no animosity between me and your dad. This is a technical forum and we could agree and disagree on some hot topics but end of the day, we could still be friends.




Bob,

You have an auto shop and if a customer arrives with his disabled car on a flat bed seeking your services. To make the story short, it has good ignition, fuel pressures within spec., would start and turnover but would only run a second or two then stall. You are beginning to suspect it could be a vacuum leak some where that causes a non-start. I could actually set a good running SC to behave like this car. So how would you test for the culprit? You think a squirt of starting fluid is a good option than a pressure system test?

Secondly, why would anyone tinker or adjust the fuel mixture without first verifying why the mixture was rich or lean in the first place? You could have a head on collision and the mixture screw setting would not be even affected. Fuel mixture is a ratio of fuel supply and air. And by nature, people would immediately go straight to adjusting the fuel mixture setting that was originally set at the factory. This is where the dilemna begins.

Tony

[Bob Kontak]

Originally Posted by boyt911sc

Gazzerr,
It is not an effective and efficient method for finding hard to find sources of air leaks in a CIS engine compared to pressure test like a smoke machine or pressurized air or immersion technique.

April,

There is no animosity between me and your dad. This is a technical forum and we could agree and disagree on some hot topics but end of the day, we could still be friends.

Bob,

You think a squirt of starting fluid is a good option than a pressure system test?

#1 Hard to find leaks is what you meant. I stand down.

#2 My Dad still has lingering resentments from you forcing him to eat a second burger. He speaks highly of you. (I just type what she says, Tony)

#3 The scenario you describe does not provide a running engine to test for air leaks. Engines don't die with everyday air leaks. They die with massive air leaks that are fairly easy to spot. So you have some air leaks and something else wrong or no air leaks and something else wrong.

I might check timing before pressures but a pressure test is required. Edit: you are speaking of pressurizing the CIS system to check for leaks, I think. I would not assume there is a big air leak in the scenario you speak of. I do believe you would have to introduce several moderate air leaks to create the no start.

[Bob Kontak]

Originally Posted by gazzerr

Seems like newer production boxes can't handle the square wave signal from the test port. Numerous complaints on this forum.

Is there value in me doing any testing with my dwell meter then?

If you pay shipping one way, I'll pay return to test your box on my car. That would put this to bed.

[Bob Kontak]

Originally Posted by boyt911sc

..............why would anyone tinker or adjust the fuel mixture without first verifying why the mixture was rich or lean in the first place? You could have a head on collision and the mixture screw setting would not be even affected.

I appreciate what you are saying.

However, when these cars (in general) started having CIS age related issues, masking them with a tweak of the 3MM screw had to have been an easy $150. I bet as many real shops (not like my hole in the wall semi retirement hang-out) drilled the plug as did DIY guys.

In post 19 I say the 3mm screw is mistakenly gone to as a "fix" before it should be. I am not saying go to the 3mm screw as the repair. I am saying go to the 3mm screw to test the functioning of the frequency valve signal, which is the topic of this thread.

[gazzerr]

Hey Bob,

Happy to send you my MA if you are interested in a science experiment with the box and the 3mm screw. I'll pay shipping both ways. Let me know.

Tony -> no worries my words were a little strong there regarding the "spray test". What I should have said is the spray test is one of tools for finding bigger leaks (and it's find of fun ) but the pressure test will allow you to find all the smaller ones too. At some point I'll get a smoke machine to make sure I really do have all the leaks plugged.

I'm gonna hit the FLAPS today and get the bits for a jumper for the fuel relay socket.

Dumb question -> when you hook up the pressure gauge do you need to burp the air out of it before performing the test?

As always I greatly appreciate all the advice from all of you. I've learned a tremendous amount from you all!

[Bob Kontak]

Originally Posted by gazzerr

Dumb question -> when you hook up the pressure gauge do you need to burp the air out of it before performing the test?

You can once pressure is in the lines. It will read fine with some air in the lines, though.

No connector on the WUR but you know this. Your CCP reading will vanish in a brief time.

[gazzerr]

Cool thanks Bob - I've built the fuel relay jumper switch and it works great. I'll endeavor to do the pressure test tomorrow.

[Bob Kontak]

Originally Posted by gazzerr

Cool thanks Bob - I've built the fuel relay jumper switch and it works great. I'll endeavor to do the pressure test tomorrow.

Saw that Summit Racing, show room just a few miles away, sells the Actron. $27.

I got an eye-dee (idea) as my 4 year old used to say, only 22 short years before he put my 911 into a tree.

I can buy the Actron there. Test it and see if it works the same as my old one with the same model number.

If it does not work, I can return it. Even if it does work, I can return it. Yes, it's cheesy, but I really want to figure this out. Worst case is I eat the $$ and that is $27 small dollars to support the fat man ego trip.

Interesting the price. I remember something like $50 in the way back. Why so cheap? Maybe cause it's different?

[gazzerr]

Hey Bob,

Interesting idea. If you change your mind let me know - I'm more than happy to send mine each way.

I'm also very interested to know if the internals have changed. I could crack it open and take a photo of the innards to compare with yours also. Perhaps it changed to an internal integrated IC (cheap), or I could find a revision to the electronics etc. I bet the guts have changed for the price to drop that much.

I suspect the old ones work because one of the side effects of the dwell setting in the electronic implementation is that it just happens it compatible with the duty cycle signal.

Did you ever get your car fixed?

G.

[Bob Kontak]

Originally Posted by gazzerr

I could crack it open and take a photo of the innards to compare with yours also. Perhaps it changed to an internal integrated IC (cheap), or I could find a revision to the electronics etc. I bet the guts have changed for the price to drop that much.

Here are my guts. Good idea.

Why don't we just make these?

[Bob Kontak]

Originally Posted by gazzerr

Did you ever get your car fixed?

Not yet. I am in no hurry. Car was salvaged. I keep her inside. Runs fine. Need to pull front end parts off and post pics of front box to gain advice.

Thankfully I like fiddling with the car as much as I like driving it so these kinds of side projects (this thread) keep the hobby going.

Have all front end parts purchased off of a single car that had an engine fire. This makes it easier for the Ohio State Highway Patrol inspection center to validate the origin of the new stuff. They assume the part is stolen unless the source is validated.

Here is the donor. I purchased all for $2,500. He kicked me back $300 if I did not take the headlights. I just like the sugar scoops.

[gazzerr]

Bob,

Awesome glad you are making progress. I hope you are back on the road soon. I would have bought those H4's and trim rings off ya .

Some progress!

First - here's the innards of my Actron. The circuit board says it's "version 2.0". So we might have a real clue here.







When I reassembled the unit the switch now works properly ...

I also did a pressure test:

1. Year of engine: 1982
2. US or RoW (Rest of World): USA
3. WUR model number: 090
4. Ambient temperature at time of test (in degrees C): 33.6 degs C
5. WUR Resistance (in Ohms): 10.1 ohms (out of spec)
6. System Pressure (in bars): 4.6 bar (seems in spec)
7. Cold Control Pressure (in bars): 2.3 bar (out of spec)
8. Warm Control Pressure (in bars): 3.6 bar (seems in spec)
9. Time delta for Cold -> Warm Control Pressure (in minutes & seconds): 1:45 (too fast?)
10. Residual Pressure @ 5 min (in bars): 2.1 bar
11. Residual Pressure @ 15 min (in bars): 1.7 bar
12. Residual Pressure @ 30 min (in bars): 1.55 bar
13. Residual Pressure @ 60 min (in bars): 1.35 bar

Based on this I pulled the WUR and I'll send it Tony for testing on Monday.

What do you guys think?

[Ronnie's.930]

Originally Posted by gazzerr

Ronnie what kind of cash have you got sunk into that bad boy?

I have about $400.00-450.00 in the PLX gear, not including the Innovate LM2 which I got tired of fixing/fooling with so sacrificed it (was inop at the time) to make the case you see for the PLX, but probably have 40+ hours in the design and build of the movable case and two hangers for it (plus the installation in general). I'm happy with the results, though, so no complaints.

Originally Posted by gazzerr

Hey Bob,


Did you ever get your car fixed?

G.

Originally Posted by Bob Kontak

Not yet. I am in no hurry.

Translation = Bob is on the 5-year repair schedule, so that means he MIGHT drive it again on his 80th birthday!!!

[gazzerr]

Cool thanks Ronnie.

[Bob Kontak]

Definitely different from mine. Let's try mailing me yours for fun.

1:45 may be too slow but not by a lot. CCP and ohms are wrong. Ohms may cause the slower WCP but not a crisis. Let Tony set your CCP.

Resid pressure is ok.

[Bob Kontak]

Originally Posted by Ronnie's.930

Translation = Bob is on the 5-year repair schedule, so that means he MIGHT drive it again on his 80th birthday!!!