Hi,
Thanks for taking a look
I have a 1971 D Jet 1.7L 914. It has been running all summer after replacing the ignition points with an electronic ignition. The only other symptoms I've noticed are:

1. It seems to miss occasionally at 2900 rpm while cruising on the highway, if I accelerate the hesistation goes away.
2. The smell of gas while driving has been present for awhile, especially after filling up. Lately it has gotten stronger. My last two drives it became significant.
3. I noticed a fuel leak under under the car near the passenger's side door jam on start up recently that has not returned.

The car would always start on the 2nd or third crank and ran great otherwise.
Saturday it started only after cranking for awhile (i.e. a number of attempts over 10 minutes) and drove fine afterwards. The following morning (this past Sunday), it would not start.
I'm confused b/c once it starts it runs great.
I know the fuel leak needs to be addressed and will be but like most teeners, she is a driving project


thanks for any suggestions

even for a driving project - a fuel leak is not acceptable.

where is your fuel pump - upfront?

No fuel pump is in rear in engine bay but no leaks anywhere there. Fuel filter perhaps? Where is that located?

not sure about the miss but, please find the fuel leak! we'd hate for another one to go up in flames.

on the cold start issue, check the cold start valve. it's like an extra fuel injector on the intake plenum towards the front of the motor.

your fuel pump is probably under gas tank and fuel is running from there and traveling to a low point where it drips to the floor.

show us some pics are here your fuel leaks from.

do you have an access panel at the back of your front trunk to under fuel tank area?

1) Throttle position switch is dirty, there are threads here on how to fix/clean that.
It may have a worn groove, and its most commonly worn at the cruising speed....cause the switch has been wearing that area for 40 years...
Clean it with alcohol, and bend he tabs slightly to touch a whole new part of the board....re-calibrate it with an OHM meter...good for another 40 years.
There are also new board available from someone here...forgot who.

2) The fuel needs to maintain pressure for your starting issue.
You may have a fuel leak in the rubber hoses that are underneath the tank.
There is a skid plate under the steering rack...remove that.
Once removed, you can see a 4 inch hole right under the tank.
Get a small mirror and a flashlight...look at the lines.
The smell in the cabin could be from a leak under the tank.
It could also be an improperly connected Evap system....the charcoal tank on top of the gas tank needs to vent the fumes into the intake of the car...
There are two hoses running along the passenger side rocker cover into the engine bay...one is hooked up to the fan to blow air...the other is hooked up to the air cleaner to attempt to burn the fuel gases that happen from heat/cool etc.


If you have a fuel leak, the resident at rest fuel pressure wont be enough to easily start the car....so fix that first, then see if it starts better.

Rich

Awesome. Thanks guys. I carry a fire extinguisher in the car at all times but she is garaged until this leak thing is situated. Hopefully it's the root of the problems I'm having.
I will take a look tonight and report back.

Next time take your battery out and charge it overnight just before attempting to start the car. Batteries hate cold weather. Before doing that, replace all your fuel lines with new ones if you haven't already. Tangerine Racing sells really nice stainless steel ones which will take care of most of your car's lines, add new rubber ones elsewhere.

Brakes and a secure fuel system are the most important issues on any vehicle.

You may have some 40 year old old fuel hoses that the 'new and improved' ethanol fuel likes to eat at. It's possible that some sludge from deteriorating hoses could also be clogging your injectors (including the cold-start injector (valve).

If you can afford it, go from the tank to the engine with all new FI-rated hoses (and the SS fuel lines through the tunnel).

Okay
So I spent the weekend with the car on jacks looking around. I found nice looking new fuel lines.
I could not find a cracked hose or loose connection under the tank, at the fuel filter or under the car. No smell of gas or leakage...
The leak I saw one time was coming from the area of the fuel filter but connections are tight and the hose looks new. No leaks now.
I removed the TPS and cleaned it. It had slight buildup. This did improve but not completely eliminate the missing around 2900 rpm.

I did get her started after a number of long cranking sessions. She runs just fine once started and I did a couple of long drives with no incident. Once warm, she starts on the first crank for the rest of the day. I no longer noticed the gas smell.

I found the only way to get it started when cold was pumping the gas??
The vacuum hoses are recently replaced and the temperature was only in the mid 50's AND the car was in the garage this weekend.
What about the idle mixture screw on the throttle body? I know you are supposed to adjust that with a CO2 sensor but it does affect the idle speed when adjusted. Could this be an issue?
Thanks for your input guys

My fuel pump would leak sometimes but not all the time. If I started the 914 every day no problem, let it sit three or four days, it leaked after starting. Do you have three prong pump? I replaced the pump with a two prong pump.

When was the last time you had your injectors cleaned? Witchhunter does a great job at a fair price. http://witchhunter.com/

The time I noticed the leak was after it had sat for about 2 weeks. Interesting. Perhaps the fuel pump is the issue?
I have never had the injectors cleaned but I've only owned the car since June.
Perhaps I should pull them and have them cleaned.

The screw on the TB is your idle speed adjustment.

Early edition ECUs don't have a idle mixture adjustment, but later editions have a pot on the top left.