robertj

My 914 recently began to run a little rough unless I stomped on the gas and always when below 3200 rpm. The other day on the freeway it started really run rough, backfire, and then the motor quit. Didn't seem to be enough eletiricity to turn the starter, but I was able to compression start it. It ran very rough, and eventually quit again about 20 seconds later and had to be towed. I can jump start it, and it seems to run ok for about 20 seconds, then runs badly and dies again. The lights don't come on anymore, and the console lights seem dim as well. The flashers still work though....I'm thinking that the alternator needs replacing. But would this account for it running rough (and continueing to run worse) up until the time it quit on me? Or are the 2 not related?

Any help would be greatly appreciated!

killbugsfast

I guess you still have FI , so , you need the pump to provide the pressure for injectors to work right . 28 to 30 psi . The ignition can still fire with little juice .

Mugs914

If your car is injected, the sputtering, coughing, dying, etc. sounds like it could be your injector points. They live in the bottom of the distributor and send a signal to the injectors telling them when to open and squirt fuel. When they go bad you get all that misfiring, backfiring, etc.. (Ask me how I know... )

As for the dim lights, check all of the ground straps, voltage regulator and then the alternator. (Always start with the cheapest thing!)

Apologies if this is old news...

Cheers!

Mike

robertj

Thanks for the input- while replacing the fuel lines, I pulled
the injectors to find that the head casing of one of them
was all cracked. Going to replace that and see if it helps.

I will need to check all of the wiring connections too, as
the console volt meter reads about 2 volts less then
my digital volt meter when testing the battery.

SF914

Hi RJ,
It sounds a lot like a battery/charge problem. Have you checked to see if your battery is holding a charge and if the alternator is providing a good charge. Also check your ground from the battery. This happened to me not once but twice while driving, the lights dimmed the car started slowing down losing power and sputtering. Turns out to be a dying alternator the first time and a poorly connected ground the second time around either way the inability to charge the battery caused it to run out of juice and failure of getting fuel.
Hope this helps
Howard

Irishdriver

Before you tear the fuel system apart check the points are OK and the open enough.

Many 914's have trouble as there is no grease on the distributor schaft and the the lettle block for opening the points wears away. This means the points gap gets smaller and smaller. The car gets slowly weaker and weaker until it eventually doesn't run.

My recommendation is charge the battery, then check alternator voltage,
Then check the points, if they are worn or pitted or the gap is small, change them (and the condensor)

If that has not produced an improvement then tear the fuel system apart !!!

Have fun.

robertj

Pulled the distributor cap off, and the points look brand new (as does the rest of the distributer. Put in new plugs as well just for good measure. After replacing plugs, car ran great for about 2 minutes. It does start right up, but idles at about 900, and dips down to 700 and back up. Adjusting the idle on the ECU to it's highest setting only brought it up to 1100 rpm. I may have this wrong, but if there's a vacuum leak, it would idle higher, correct? I need to measure the fuel pressure next.

Rouser

Yes, you do have it wrong; the screw on the ECU is NOT an idle adjustment, it is a mixture adjustment. Your hunting idle may be a result of you messing with this screw, causing it to intermittently run rich.

Check P.B. Ander's D-Jet FI site and it should steer you in the right direction.

robertj

I adjusted the screw on the ECU AFTER the idle problem came up as instructed to do so by another 914 owner simply for testing purposes....