Clark I know you have been having issues here. Make no mistake I have zero L-jet, D-jet or any other Bosch injection knowledge. Its not what I do. But the guy that owns the shop I manage is a Bosch fuel injection whisperer. He was a Porsche and Audi factory trained technician in the 70's and 80's. He is a very cranky old coot and hates to be bothered with much of anything.

That being said I brought up you issues with him. Of course he told me that vacuum leaks are huge on these cars. I discussed with him what you have done so far. He asked me if you popped the top on the AFM and manually played with the flap with the engine running? So have you? Also he mentioned that there are small adjustments that can be made to make up for a worn engine by popping a cap on the AFM and adjusting it?

But most of all he said it sounds like to him that you just have a bad AFM. I hope something here can help you if not maybe PM me and see if I can talk him into taking a phone call from you.

Have you checked the continuity of all the wires going to the brain ? Reason I bring it up is I was cleaning a space FI harness and noticed some worn wires

Have not opened this, newest AFM. I know about the "playing with" deal and hope to get to that point. I am going to have to find a way to hold the idle. It won't idle long enough for me to even get out of the car and grab the TB cable. broom stick time i guess.

3 years ago, I did "adjust" the spring on original AFM when i made the engine a 1911.

I thought my 2nd AFM might have been bad. It was old, previously rebuilt, guts were kinda rusty looking, but then I put the guts of my bent one into it. The car acted the same with AFM #3 (guts from #1) as it does with #2 and now #4. I think "bad AFM" may now be ruled out or at least put on the back burner.

a bad ECU has been discussed, Not sure if there is a test for that. I think I could ring out the wires easily enough tho.

I was on the phone with him, turns out that his plugs are fouled (except number 3 cyl, possibly from his intake leak). Clark, you should post the picture of your plugs on here for others to see.

I think he's running rich. I tasked him to attach a air/fuel gauge analyzer tomorrow and document the readings at different RPMs.

I will ask him tomorrow if he knows a way to test an ecm... but I imagine he will probably mention a break out box or something of that nature.... but then again maybe not.

Ok, thats good stuff.

So take this for what it's worth, which is not much, but have you checked the two seals on the oil filler cap for your vacuum leak? Seems too simple, I know. I'm no mechanic but I have read a number of threads where this is an often overlooked place. Just spit-ballin' here... carry on.

Here are the plugs. I think they have about 20K miles on them. I replaced with new tonight. truthfully #3 is not that much different. You can see just a bit of white ceramic, but not much.

Click to view attachment[Click to view attachment
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They look a bit rich, but I not seeing anything here that stop the car from running. I have pulled much worse from late model cars that were running fine.

I have heard that too. Back when the car would run.... I actually pulled the filler cap off once.... the car died.

The seals are there, they are flexible. Not really sure how to test them. This might be a good place for that $800 smoke machine.

Maybe I can find some other way to cap the oil filler off to test it? I'll look at them a little closer. I have replaced the cork seal there tho.


Lots of stuff plugged up for testing.

Click to view attachment

Is the oil filler gasket is good shape ?

Clark any decent shop has a smoke machine for evap testing. I'll bet if you asked a shop to smoke test it while you look for leaks you'd probably find alot shops would charge you nothing.

Plus you got that yelp review on that volvo shop. Tell them you'll delete your post if they smoke your car... just an idea.

I have been thinking about asking William Greer if he has one. Have not seen him since Okteenerfest. But he has helped me several times. He and his brother are big 914 guys within yellin' distance from here.

I think borrowing the tool is the only way. I really don't want to haul it anywhere, until I totally give up.

How bout you call Snyder and ask him to come see me. maybe he can plug the leaky volvo while he is here.

As a shop manager, I can tell you for a fact you have leverage here. Bad yelp reviews are a dead blow to an auto repair business. If you 1 stared my shop and asked to use a smoke machine at your house to delete your post, I would be there with a smile on.

Check to ensure that the plugs are on the injectors...and the correct injectors. If after changing the gasket you mixed them up on that side it will run. But poorly and very similar to what you describe.

Clark, I'm all for temporary isolating auxiliary peripherals when making a diagnosis, but you may have taken it too far. The aux air valve and decel valve can definitely be temporarily removed without any ill effect to how our engine runs. However, I believe the pipe you labeled as "oil funnel" in your picture does serve a purpose and needs to be connected.
The Ljet's airflow meters flap is quite reactive to air buffeting. Ever watch how much this little AFM's arm dances back and forth at idle? This oil funnel pipe helps equalize the turbulent pressures between the plenum and crankcase. I believe the airflow meter will behave differently with this "oil funnel pipe" bypassed, therefore it should really be connected.

Also, after seeing what has been bypassed in the picture, I noticed (I added a red arrow) that the plastic stacked T is not capped?
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As I have already mentioned to you that I'm not a fan of bending over hoses and zip tying them. They sell a grab bag of various caps and plugs in different sizes, this would be far better than what you have pictured.

Tim, you are good.... I wondered if you would notice the UNPLUGGED "Y".

Both of the connectors on the intake elbow are "home-made". Garold got me a couple Y's and I modified them. On the top one, with orange paint on it, has been cut to make a single out of a double. I used fiberglass to seal up the hole.

The bottom one remained in the "Y" shape but I filled the un-used portion with fiber glass resin.

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I will head to Ace Hardware and AutoZone and look for "Tim Approved" plugs and caps...

I had a thought.... would there be a way to get "smoke" of some sort into the vacuum tester Zach linked to? anyone ever done that?

I have never seen any one rig a smoke tester out of a vac tester. One thing I have seen people do is Jerry rig a party fog maching as a smoke tester. I don't know if I would recommed that route, but its been done.

Might try the VAPE shop.... wouldn't that be similar smoke? Doesn't the smoke still act as the AIR and need to be mixed with fuel and burnt?

The smoke machine and vacuum tester are used with the car running or not running?

Vac tester has a ton of uses, depending what you are using it for the engine could be on or off.

The smoke tester is used with the car off, and is hooked up to air pressure from an air compressor usually regulated down to somewhere around 1psi. You T into a vac line ant turn it on. It blows a constant flow of 1psi smoke and you watch where the 1psi smoke is coming out of the engine. Naturally smoke will come out of the throttle body, so I usually tape it up.

I would watch a youtube video so you can see how it works.

WOW, what did we do before YouTube. I did a Smoke Detector search and BAM. videos galore. Most are DIY making a smoke detector. Some are elaborate, some are not. I am gonna use some of the best features of several of these guys.

Charcoal and card board, or incense. a mini compressor a paint can, some RTV.... I am kinda fired up now..... I bet a nickel I don't find anything.... I am just pessimistic tho. I will put my work on YouTube too! Then we can have a 914 gettin' smoked for the world to see.

https://youtu.be/FFlyAqiYMro

Nothing positive to report from last night. Got the exhaust back on. put some "Tim-approved" plugs in the correct places..... re-attached the oil funnel, removed the AAR, DECEL and plugged them up tight.

Started the car, I even let it warm up, got the CHT to 250-ish. Car still won't idle and runs kinda ruff at 2000.

Even my borrowed A/F meter did not work correctly. Gotta figure that out too.

https://www.youtube.com/watch?v=rBT1FP131Kw


As I mentioned, I now have made a crude smoke tester. WHile I may not have found it all, I have at least found something to fix.

So the question is, while I wait on my $20 TB seal, has anyone ever RTV'd that connection, even for a short term fix?

BTW, the cover shot of this vid is my car they day I bought it in 2011! Does not look much different on the outside.

Way to go Clark! That is a really cool smoke tester. You have inspired me to build one as well.

I think you were 1st to mention the smoke idea, so I give you all the credit.

I went with an outlet hose large enough to replace the DECEL hose. I think I will redo that and use a smaller hose and fitting. I believe the pressure will go up and the volume of smoke will go up too.

Gotta find a place to attach it, then buy that size. It worked so far, So I am gonna start plugging vac. leaks.

One thing I wanted to ask is how much pressure are you forcing into there? you really don't need much, too much pressure and your going to create leaks. I think adding a pressure gauge on the paint can would help. I would never run more then 5psi. You never really have a reason to run more than about 2 psi.

I should have pulled the hose and showed the flow. But I set my compressor low enough to just barely blow...then I turned down the HF ball valve to almost closed. on the shot of the valve, you can see where I used a sharpie and marked the CLOSED position. I don't think it is much more than 3 or 4 psi.

Do you have a good gasket between the throttle body and the plenum ?

Jim, yes there is a seal. It was new in 2013. I borrowed a TB while mine was being re-worked back in November, did not change the seal then. Got my TB back and did not change the seal.... I guess I should have.

I used some sealer on both sides of the TB seal as a temporary stop. Bought a new one, probably won't see it til later next week.

So tell me about the dip stick.

I now see a bit of smoke coming out of the top of the stick tube with the stick inserted. Is there a seal for that? I picked a bunch of fiber looking stuff out of the little "hat" at the top of the stick.

I bet I can make one with an o-ring or cork. But my question is how do I get the dip stick to measure properly after I add a ho-make seal?


Probably talking about a few mm one way or the other. Does it really matter that much?

Take out the dipstick and look at the distance between the "full" and "add a quart" marks. Decide if a couple of mm will make any real difference to you. If so, re-mark the stick. A file should do for that.

--DD

I think we can OFFICIALLY close this posting. What a great day. The Throttle Body leak was the only big one. With the temp. RTV on it, the car now starts and idles !!!

LORD L-Jet (Timothy_ND28) has walked me thru many tests and AFM adjustments using a suspect A/F meter today. and we got to here.....


https://www.youtube.com/watch?v=BMspGlzl6Lo


I am so thankful to everyone that had direction for me. In the end it turned out to be ONE HELL OF A VACUUM LEAK. I now see why people give up and put on carbs. I say DON'T DO IT.

Then the need to tune the 1.8 AFM to the 1911cc engine. I ended up adjusting the AFM gear about 20 teeth. That is nerve racking! Now Tim thinks I should put the OTHER spare AFM on and adjust it.....Great to have a spare, right?

Car is running great, idling great. THANKS TO ALL.

Clark brother, I am seriously glad you got this thing going. Good work man.

Great news ! What does the 20 tooth AFM adjustment do ? And what are you looking at to judge its right ?

My engine has been converted to a 1911 cc from the 1756 cc (1.8). The original AFM was setup for the 1756 so to get the 1911 to run properly it has to be re-adjusted by changing the spring tension. The spring is wound up inside a big toothed wheel. So you move teeth to adjust.

Since my backfire bent my AFM i had to get a new one. So the AFM was not my problem, but i could not adjust it til i got the car to run.

I used an Air/Fuel gauge to measure the changes and fine tuned the amount of fuel the AFM tells the fuel injection sys to give the engine.

Interesting; after upgrading recently to 2L and installing the Vanagon TB, I had wondered whether any correction is needed. It runs good and AFRs were within range

Adjusting the airflow meter is something that I would not recommend as they are calibrated from the factory. In most all cases, you can simply plug and play a new AFM straight out of the box with no issues. However, not so much in Clark's situation.

Clark had a air/fuel gauge (an awesome tool) which painted a picture on how the engine was doing.

At the beginning, his engine was running 18.0:1 air to fuel mixture, which is very lean. His meter seems to be pegged at 18.0:1 throughout the entire RPM range.
Feeling confident that he rectified all vacuum leaks by use of his ingenious vacuum leak detector, I felt we could proceed with making adjustments.

We also needed to make sure something screwy wasn't going on with his ECU, so I had him plug his spare cylinder head temperature sensor into a glass of ice while the body of the sensor was jumper-ed to the negative battery post. After rerunning the test, the air/fuel meter changed slightly from super lean, to not so much lean. This was encouraging and proved that the ECU does work and altered the air to fuel mixture in regards to temperature.

At this point, we made baby step adjustments to the AFM. The big clock spring controls the tension to the AFM's flap. Relieving spring tension will make the car run richer. Fine tuning is still needed because the air/fuel meter seems to be fidgety and doesn't seem to have the resolution for a finer tuning. 20 teeth seems like a bunch, but I have a feeling with a new gauge, the final answer may be closer to around 14-16 gear teeth (CCW from the original position).

Thanks for the explanation-

A tribute to persistence and ingenuity. Congratulations!

Wow, very nice! Glad you found that leak.

Where did you get the A/F kit? How much?

I borrowed it from a friend. It has a pipe that goes in the exhaust with the sensor on it and a cig lighter plug for power. I am not 100% confident in it. I plan on looking for one to buy. Might even install it in an extra spot on the dash.

Throttle body gasket was one of my leaks. Glad you found it!

The leak was so bad that the car would not run. Making it difficult to use the starting fluid method. That ho-made smoker was perfect. After i fixed the TB leak i saw some tiny streams in a few places.

So i have a few more leaks to get. But I am gonna drive today. She has been on jack stands since before Christmas waiting on me to get to her.

Well, I hope that's the last of the major troubles for awhile. Between the 914 and the Volvo, you've had your hands full!

wow big thanks again for various members here especially "the Ljet man" Tim who is always there to help us. He did helped me before and he really did help me go through various steps to fix my electrical issue on my 75 1.8 Ljet. I may be asking his help soon on my minor backfire if this can damage my AFM flaps.

Good to hear your car is running now!

Yep, i now believe the backfire will do damage. It was a low, different sounding backfire. They call it an internal backfire.

So, i suggest you buy a spare afm and tune it in. And you make a smoke machine and use it a couple times a year or when ever you change any induction part.

currently, my car runs well on all gears and 800 to 900 rpm on idle when it is in normal running temp. No hesitation when I accelerate. I get the small backfire when I slow down only. Usually just before I downshift.

I have been playing with a AFM on my L-Jet and am a bit skeptical of the 02 sensors at the tail pipe. I think the readings can very there. I am planning welding in a bung and getting the 02 sensor further inside the exhaust.

My car seems lean at idle. There are a few videos on youtube showing the procedure of the two ways to change the mixture on the flapper box.

Keep posting your results.