'73 1.7 will not start

[mkinne]

On my way to work this morning, about 3miles from home, the engine in my 914 ('73 1.7) suddenly died. I coasted into a parking lot and could not restart the engine. Cranks like crazy but will not fire. Got the car home and, in the little time I had today, found out the following:
Plenty of gas in tank.
Fuel pump runs normally and provides 30psi while engine is cranking. Pump was relocated to front of car long ago with stainless lines running back to engine. Fuel filter is less than 1year old.
Timing gun picks up pulse in all four plug wires while cranking. Plugs and wires are due for replacement.
Distibutor cap and rotor look good. I have a Compu-Fire unit (model VW-1) in distributor and the magnet disk has rubbed slightly on the module. The sticker has been obliterated.
There is NO smell of fuel at the tailpipe.

It is as if the injectors are not firing or I am pumping something other than fuel to the engine.
Tomorrow I will check to see if injectors are getting power. What kind of signal should I expect when engine is cranking? Could the brain have failed? All fuses (that I can find) and relays appear to be in good working order.

This failure was VERY sudden. The car was running great up until that instant. This has been a reliable daily driver for the last 3 continuous years. Any comments / suggestions will be appreciated. TIA.

[Brister]

I believe you stated you had an electronic module in the distributor so this may not be applicable.. my standard distributor was the culprit in a similar situation ..running fine, turned off the ignition, tried to restart and nothing. The problem turned out to be a broken ground wire, in my case soldered to the plate on which the points are mounted and the plate to which the vacuum advance is connected. A brittle solid wire had been soldered between those two points. I used solder wick, which can be purchased at Radio Shack or any electronic supply house. It is thin braided copper wire about 1/8" wide, providing flexibility. Since that repair a few months ago there has been no further ignition problem.

[mkinne]

Thanks Brister, but ground wire looks fine.

Here is some more info:
Spark plugs 1 and 4 are grey / white and dry. 2 is black and slightly crusty. 3 is black and wet. This after much cranking and no running.
Injectors 2 and 3 click once when key is turned to run. Injectors 1 and 4 do not. None of the injectors click while cranking.
Both leads to each injector are continuous to ground with key off. Is this normal?
I can sense no voltage between injectors leads while cranking. Not even a flicker on the DVM. Meter may be slow but I thought I would see some activity.
There is 250ohm thru temperature sensor I to ground (thru sheet metal near right hand cyl ead).
There is 1.3kohm thru temperature sensor II (screwed into intake manifold).
Any more suggestions?

[JP Noonan]

I've seen CDI units fail where they still put out a spark, but it was so weak it wouldn't ignite. So make sure that the spark is big and fat at the end of the wire.

The injectors only fire two at a time (on D-jet anyway) so that's normal. Try key on engine off and use your hand to move the TPS, you should hear 20 clicks from the injectors through the TPS full range. If not check the FI points in the dizzy and the ground point under the intake.

Make sure the FI points, the CHT (you did check it with it unpluged right), and that the MPS connectors are in good shape. Unplug them, use contact cleaner, and plug them back in.

Try starting fluid, if it works than there is a fuel problem. If not, it is ignition.

Also look at the D-Jet article on the 914 fans web site.

Also make sure the relays are working and getting power, swap them around between the FI and the pump relay. See if the pump still runs. Or you may be able to feel the relay click.

[This message has been edited by JP Noonan (edited 06-27-99).]

[Dave at Pelican Parts]

The acceleration enrichment is separate from the trigger points circuit.

I would suspect the trigger points, the contacts in the trigger points plug, the wiring associated with those points, and the multiple ground point at the top-rear of the engine. On a 1.7, it may be buried underneath the manifold, I'm not sure.

Try checking the grounds first--they often get kinda nasty and grotty. Squeeze the female spade connectors a bit to tighten them up and re-install. See if that helps. Then start checking the trigger points circuit.

--DD

[John Rogers]

Our 1974 2.0 stopped several times on Friday and after a little time would restart? Julia was about 1/2 mile from home and it stopped for good. She called and when I checked it, I found the spade connector to the temp sensor on top of the engine had come off and had grounded. As soon as I moed it, the engine fired right up. I crimped the spade lug a little and put it back on. Seems like it gives the brain a 0 ohms signal so it shuts off? Check yours for any loose wires or connectors that could cause the brain to shut off.