Hi all, new here needing a little help. Let me give you a quick backstory. Picked this car up on Friday. It’s a 73 1.7. Against my better judgement I decided to drive the car home, it started up fine, ran fine. 30 minutes into my commute it’s smoking BAD. Have it towed home. After looking around for a problem I noticed it was missing a hose from the flashback valve (?) to the passenger side head and was pretty oily in that area so assumed it was spitting oil on top of the engine hence the smoke. Replaced the hose. Went to fire it up and it won’t start. Engine oil level seems fine so it didn’t lose much. Any ideas why this would start fine before the incident and now it won’t? Thanks for the help in advance.

Does the engine try at all to start? You know, a little bit of chugging and some cylinders firing?

A quick analysis would separate a fuel related issue or electric.

Does it have fuel injection or carbs?

If you squirt some starting fluid in the intake, does it try to start?

How much gas is in the tank?

Thanks Spoke! It turns over but there isn’t really any chug to it. It’s fuel injected. Full tank of gas and don’t have any starter fluid at this moment. I haven’t changed anything since it’s last started except the missing hose so it’s a bit puzzling to me.

Do you hear the fuel pump prime for half a second when you turn the key to the run position? Not start, but run.

Recheck area you reinstalled breather hose. CHT, coil conns may have gotten disturbed since they are around that area.

Fuel pump does prime. Looked around the area of the breather hose and I don’t see anything loose. Where is the CHT located? If I let it sit for a few I feel like I almost get a little chug out of it.

CHT BELOW #3 spark plug.

Is the fuel pump in the stock location underneath front of the engine? Might be vapor locked? Or if the alternator isnt charging the battery you might have drained it enough so it doesnt have enough ooomph to start..... check the voltage while cranking.

Reset points, clean and lube rotor shaft

Taylspin- CHT looks fine.
Falcor- I believe it is. No reason to believe it has been moved. I unfortunaty don’t have a volt meter at the moment. Dumb question coming... if it’s vapor locked, how do I fix it? Seems like it could be a possibility with the heat that was coming out of there.

Thanks everyone for all the input. The 914 community truly is as awesome as I’ve been told.

Vapor locks go away by letting the car cool down, I've never experienced it so I dont know how long you have to wait really.

The engine needs three things to run: Fuel, air, and spark. Do you smell fuel at the tailpipe after trying to start the engine for a bit? Tape an extra spark plug so the threaded part is touching a ground and hook it to a plug wire. Do you see sparks when you crank the starter?

Checking the compression requires a compression tester, so assume that it is OK for the moment....

Inspect all wires and hoses in the engine bay. Are they hooked up? Solidly? Anything broken?

Sudden no-start problems are often electrical problems. It's not that hard to knock a wire loose... Sometimes a connection comes loose but still looks OK from the outside, so sometimes you have to wiggle the plug or the wire a little.

--DD

Smells funny to me.

I get something can go wrong on a drive home. But how did you get from healthy to smokey, to you figured it was a missing hose? What is your knowledge of a flashback valve in 914s?

**Update** sprayed some starter fluid in the intake and got it to fire up. Running extremely rough and if left to idle for a while will die. Also shot a little black stuff out of the tailpipe.

If you haven't done a tune-up on your new car, it might be time.

Yea, I’m thinking about taking it to a local Volkswagen guy here in town.

Any idea where these lines go? They appear to just be open.
Click to view attachment
Click to view attachment

Not sure what that is in the bottom picture, but the top picture is one of the lines that goes to the fuel charcoal canister up front. The "fuchsia" (magenta?) lines in the picture below:

Does that one in particular just vent to atmosphere?

Could these be the hoses from the charcoal filter to the fan? Check your fuel line for good flow. Sounds like you have a fuel delivery problem. There are screens in the tank nipples that can become clogged. Your fuel pressure should be about 29psi.

I’ll give that a shot. Taking it to a friends this weekend and putting our heads together.

One of those hoses goes from the fan shroud to the charcoal canister up front. The other one goes from the canister to the air filter. It basically dumps air with some fuel vapor into the intake upstream of the throttle body.

I don't remember which is which, but it's not a good idea to swap them...

--DD

Well there’s already one going to the fan shroud so I guess I just need to figure out which one goes to the TB. I have a capped port on the TB so I bet that’s where it goes. Not sure why it would be capped though. Thanks for the help.

I started the car when I got home from work yesterday (ya know cuz these things just fix themselves right? Lol). It fired up easy, didn’t give it any gas. Sounded normal for maybe 3 seconds and then fell into a rough idle slowly dying.

The other hose doesn't go to the throttle body, it goes to the air cleaner.

--DD

What is the ohm reading on the CHT sender when it dies; have you checked the MPS for leaks; does it die about 5 minutes after start up?

Haven’t gotten to ohm readings yet. Thinking it’s fuel related. Took the tank out and cleaning it up. Going to replace the pump, filter, and lower lines then go from there.

**BUMP** Update, car starts now. Will run and drive but not great. Pulled the a spark plug and they look like this. This is brand new. Lol. Ideas on what would cause it to run this rich? Click to view attachment