Brain Teaser

Years ago my fuel pump stopped working, I used the universal adjustment tool (hammer) on it and it worked sometimes. Any time it didn't work, I would hit it and it then worked fine. I had forgotten all about it as it has been working fine for years and it had never been fixed or replaced. Hope I don't jinx myself.
Spraying starter fluid in and getting it started may have given the fuel pump an extra bit of voltage which got it to start up, maybe?

 

There is the CIS air flow metering switch on the Fuel injection distributor box. If your sensor plate was stuck and not moving I believe this inhibits the fuel pump. Perhaps just cranking you weren't able to get enough air flow to pull the sensor plate off this switch. By using the starting fluid you got the engine to suck enough air that it did dislodge the sensor plate and allowed the fuel pump to start running and the sensor plate to start metering fuel. You might want to check your sensor plate in the fuel injection distributor and see if its sticking. If it happens again, you should be able to unplug this switch and get the motor to fire.

Otherwise you may be correct that its a funky spot on the fuel pump windings or perhaps just a bad fuel pump relay. But your use of the starting fluid seems to override those in my thinking... unless it was just a really odd coincidence starting working the very time you used the starting fluid.

Just a SWAG...

Rick

 

Id put my money on a temporary sensor plate being stuck.

 

The airflow sensor plate will stick if the central piston in the fuel distributor sticks. If your 1988 Mondial is indeed a CIS K-Jetronic car, the following discussion pertains. If not, well....???

The central piston may be gummed up by years of gasoline flowing thru it, and yes, the fuel pump will not run if that plate does not move a bit. There is a microswitch on the airflow plate that controls the pump.

On thing I did not get from the original post, how long did the car sit before it would not start ?? If it was a few weeks or a couple months, I would think it was the fuel distributor central piston.

The cure for this problem would be rebuild the fuel dist. per the posted procedures, or drive it more often.

 

You are correct that the non-movement of the air flow plate will prevent the fuel pump from running, but I believe that the starter motor circuit overrides this and operates the fuel pump relay to run the pump while cranking.

 

It's all within the fuel injection assembly. Pivot for the sensor plate and the piston/valve inside the distributor head are on the upper shell. I'd tread lightly here. If you are unsure or unfamiliar engage a local pro or send your parts to Larry Fletcher. I've got mine all torn down and waiting to get my parts back from Larry this week. You can see sensor plate in picture 034 and the piston in picture 048. Be careful, there is a spring deep inside there too.

http://www.flickr.com/photos/moseley_ferrari/sets/72157622414223889/


Rick