Update: No new engine for me right now, the 1.8 is once again running strong. Thanks everybody for looking at my videos and posting in this thread.

Paul


Edit: I added some video of my 1.8 engine's behavior. What you are seeing is about 2 minutes into the engine running from a cold start. I tried to capture a little of the shakiness of the engine as well. Wondering if anybody has a good idea of what's going on as I may want to sell the engine after the swap.

914 1.8 Stalling

Original Post:

So late last "season" (Porsche weather is May to November here in Michigan), my car stalled between shifts. Started up OK but conked out when warm. So...I discovered a disconnected hose and started a hose renewal project. After replacing every hose, the problem persisted. But along the way I had to replace the AFM as the car backfired and warped the flapping door. Still no success. Replaced the fuel injection seals, oil filler cap seals, still conks out after warm up. Contemplated a new brain and wiring harness and cylinder head temp sensor but have run out of patience.

To make a long story short, I've decided to go with a 2.0 and plan on dropping my car off at Brad Mayeur's next weekend. I've always wanted more power anyway.

Questions:

1. How much power am I losing by sticking with the stock 1974 exhaust system?

2. What to do with the 1.8? It ran strong before the problems developed, but the car is of unknown mileage. Seems like interest in these engines is, well, underwhelming. Brad said he has more than enough of these engines.

3. I'm sure he could get the 1.8 FI running on the 2.0, I know there are proponents of the L-Jet...Is that something worth pursuing or stick with the D-Jet?

Thanks,

Paul

BTW, I have a pristine orange 1.8 that is staying stock. This is for my red driver!

For every question you have, ask Brad, and trust he will not steer you wrong.
He is an honest gentleman with a solid knowledge of these shitbox cars.

Rich

I agree, he's the best. Just thought I'd solicit other opinions. It's fun to scheme and I value what the community has to say. For instance, maybe selling off parts of the engine would get me more money than it's worth on trade in?

Paul

Cost is the killer to completely replace the system to djet.
Brad will have everything you need.

74 exhaust for the 1.8 versus 74 exhaust for the 2.0 liter power loss will be so small it may not be worth it to replace.....maybe 10hp

Motor difference, once he is done...figure about 20-30hp more.

I've installed the L-Jet on a 2.0 and liked it. The car didn't run when I got it so no direct comparison with the d-jet.

on Brad great guy very helpful to any and all,honestly the the power loss wouldn't be 10bhp more like 5bhp and would be hard to notice 'seat of pants'.
A good aftermarket muffler may give you a 5bhp gain for example.
Work on what you have lots of people on here to help ,good luck.

Thanks as always! I probably will stick with a stock exhaust. Now that I have ringing in my ears, I like a quiet car. After all, it's the driver!

Paul

I added a short video of my car running:

Longer Video

Tell me what you think, thanks.

Paul

My 1.8 L-Jet is doing the very same thing, stalling at idle. I discovered that the vacuum retard on the distributor is leaking air and not retarding the timing at idle, and ?I think that nay be the problem with mine. Maybe yours too.

Lean.

Long video, under 2.5 minutes. Me starting the car cold..


Thanks for the replies. The tailpipe seems to spew black droplets so I thought the car might be running rich. I'm much better at replacing the headlights than I am at fixing engines!

Paul

Funny, a surgeon with precision hands trying to save a 914 from flatlining!
Your car is in great hands with Brad, but you already knew that.

I would say that a complete Ljet kit in known running condition could bring in 500.00 easy.

Ha! My hat's off to you, Tim. I'd like to say thanks for that cold winter weekend when you had me testing the engine harness wiring via text. Just another great example of how this 914 community is THE BEST!

Paul

As I am a DIYer, I would take L-Jet over D-Jet hands down. It is simpler and arguably a bit more modern that D-Jet. Fewer components to fail, and it is original to your car. Other than the placement of the plugs on the 2.0, nobody will ever notice that you aren't running a 1.8, except for you when you hit the throttle. I would also stick with the stock exhaust, unless Brad happens to have the 2.0 goodies in stock for a reasonable price.

Brad can and will get it running correctly for you, and I think that you will be very happy.

I'd stick with the L-Jet. More modern. I once looked at putting L-Jet from Volvo on a 2270 build. It was definitely doable, but the programming of the ECU was problematic (just not as easy). What was easier was going with a MegaSquirt setup.

Porsche opted to put the L-Jet on the 76 912E. Work through the L-Jet bugs.

Just remembered something else. Did you check the seal in the oil cap filler? Maybe a new one might help.

Over what? Over a good set of tuned headers, like Racer Chris', you're giving away a pretty fair amount, on the order of 15-25 HP.

Over the stock 2.0 HE/muffler setup, giving up very little if any.




Sell it to a Bug guy? Use it as the base for a 2056cc or larger engine? Put it into a Beetle yourself?



Either should work. Either way I would make sure that the mixture is reasonable throughout the RPM range; a wide-band O2 meter would be a very good idea.

--DD

Yes. The red rubber seal was black and so hardened/brittle I had to cut it with tin snips. I replaced both seals. Every time I replaced a hose or the AFM rebuilt or injector seals I had hope it would run. I see there is love for the L-jet but I gotta tell you this vacuum sensitivity is making me nuts!

Paul

Thanks for the advice. I have lots to think about!
The Tangerine headers just won't work for me and my desire to have a quiet car, power be damned! LOL

Paul

If you decide to put the L-Jet on the 2.0L, keep the 2.0L intake runners. The 2.0L runners have three holes that attach the runner to the head. The L-Jet 1.8L has 4 holes that attach the runner to the head.

If you look up L-Jet on Google, there is a great document out there that outlines what all the components do, how to check them, troubleshooting section, etc. It was written for the 912 version of L-Jet, but almost all of it applies to the 914.

Keep the L-Jet. Instead of just replacing parts, start checking them out. You should be able to narrow down the culprit pretty quickly based on the car dying when warmed up.

Since it sounds like it came on abruptly, instead of slowly over a matter of days, weeks, months. I'd say it is a component that failed or is failing versus a vacuum leak. With that in mind, have you checked the AAR (Auxiliary Air Regulator)? I didn't watch your videos, but you have TWO systems at work when the engine is cold. The cold start valve (Whether it turns on or off on start is controlled by the thermo-time switch) and the AAR (has it's own internal heater). The cold start valve injects more fuel into the plenum at cold start. The thermo-time switch detects that the outside air is cold and then (if I understand the theory correctly) the FI brain enables the cold start valve for a matter of time (something like 8 seconds total). The AAR on the other hand will stay open until the engine warms up enough to warm up the heater in the AAR. Once warm, the AAR eventually closes. The air that the AAR receives has been metered by the AFM (but not the TB) and so the amount of fuel will have been metered. But after the engine warms up, if the AAR doesn't close, I believe you'll run into a lean condition that could cause the engine to die.

Good news? The AAR can be cleaned fairly easily once you pull it off the engine.

More good news? You should be able to check AAR operation fairly easily by pulling the vacuum line from the AAR and capping it off at the plenum. If you do this, I would suggest unplugging the cold start valve as well so the engine isn't getting lots of extra fuel but no extra air at startup. It may make starting the engine a little more difficult initially, but once running you'll be able to identify if the problem lies with the AAR

Where did you get the new red rubber seal??? I just posted earlier today that I am looking for one but having trouble finding a supplier that either carries them or has one in stock.

Should've known it was on Jeff's website...

http://www.bowlsby.net/914/Classic/zTN_Man08.pdf

I get a lot of small parts through Brad Mayeur at 914ltd. He knows my car so there's no guesswork on what part I am ordering. His prices are competitive.

Paul

I thought about the AAR but did not check it. The car is taking a trip to Brad's this Friday so I will not do further diagnostics...but I will talk to him about keeping the L-jet.

What's a TB?

Thanks for the detailed analysis!

Paul

TB=Throttle Body

Yup, knew about the trip but thought you might want to give it a shot before heading to Brad's place. Could help if you decide to sell the L-Jet. Complete known good condition versus had issues when pulled.

So if I plug off the AAR, the car shouldn't stall because it would be as if the AAR closed properly?

Paul

I just looked at the longer video and noticed the oil tower doesn't have a hose attached to it, was this capped?

Click to view attachment

If you mean the giant 21mm hose on the oil filler, it's there! Connected to the S-hose.
Actually, the only thing different about my setup is the absence of a charcoal canister.


Paul

Theoretically, yes. If that's where your issue lies.

I may have a canister if you need one.

Hmmm. Came on abruptly. Stalls when warm. Fades under power. Backfiring...

Have you checked the ignition coil?

Thanks. I always wonder about how important the canister is; I've seen pics of other engine compartments without it...

Paul

No, but I may bring a new coil I have with me when I go to Brad's. Thanks for the idea!

Paul

I might be interested in the motor,if you go with a 2.0.
Thanks Grant

Mine did that exact same thing. When I installed a Pertronix it went away completely. YMMV. FYI as long as the exhaust is a pre-'75 there isn't a ton of difference in the flow between 1.8 and 2.0. It's the later 75-76 cars that get choked by the single pipe vs dual pipes setup.

On the road to Brad's...updates soon!

Paul

So, went to Brad's. We went out for lunch, his mechanic Michael played with the DOUBLE
(DUAL?) RELAY and when we came back, the car was running like a top! So, I am putting off a new engine and will maybe put the money into a new paint job instead. In the meantime, I need a "new" engine harness and other odds and ends so I hope to pick the car up in a few weeks.

Paul

Brad is not just a good mechanic but a great friend to the 914 community.
He could have sold you a new motor....

I had my two buddies with me, one who would opt for the new motor and one who says leave well-enough alone. Anyway, I think Brad and Michael are a bit relieved because they are just sooooo busy!

Brad is the best.

Paul

So what was the solution to the problem of it quiting?

Looks like the Dual Relay had a faulty connection. Unplugged it, replugged it and the car runs great.

However, the engine harness is brittle as heck so a better used one is being installed.

I have no idea why it seemed to be simply related to the amount of time the car was running. Guess it wasn't after all!

Paul