328 runs for 2 seconds

The car starts right away but runs for 2sec only, new fuel pump working ok ,free moving air plate, good spark,
It looks like the distributor is not taking over the problem just started.need some help from the experts

 

I owned a 328 for a decade and now have a 3:48. But I had a problem similar to yours and it was a bad fuel accumulator. This is not to be confused with the "fuel damper" this is the fuel accumulator and it's located down next to or near the fuel filter area. As I recall it cross referenced to a Mercedes 450 SL... God knows if they're still available but I'm sure others might chime in but I replaced it as a simple bolt-on part and the problem was solved.

 

Why is the fuel pump new?

 

The old one stopped working and after the change the problem started

 

I would presume your pump has swallowed lots of debris. These would be now in the K-JET.

Do you have a pressure k-jet gauge? these are chap and very handy when it's time to troubleshoot the k-jet.

 

I'd guess fuel accumulator as well but its easy for the tech to check. There's specifics that can be measured. Could also be the cold start regulator.

One good thing about the 328. Its basically mechanical fuel injection so there's little mystery in debugging them.

And its extremely similar to millions of Mercedes, BMW, and who knows how many other cars made in the 80's. My point is, its F1 system is not something to really fear.

 

I feel like there is information missing here. Is this a sudden issue? Or is this somthing that has arrived after some work was done.

 

The problem started AFTER the fuel pump was replaced. I consider that an important clue.

 

Have you put pressure gauges on it? What was the reason for the fuel pump change..

 

Sigmacars is the OP. I am just a kibitzer.

 

Fuel accumulator is unlikely, once the car as starter, the fuel pumps are operating and the accumulator are not required any-more.

I would rather suspect a clogged WUR: if its inlet port is clogged, the control pressure raises a lot and blocks the distributor (which would be consistent with the car stopping after a few seconds, i.e once the pumps have raised the pressure).

 

The fuel pump just stopped working it was over 20 years old the car run very good on the test drive but next morning the problem started
It starts right up with high RPM for 2 sec and stop ,the pressure with the new pump is just over 5 Bar I just like to know where to start bevor I get to the Distributor

 

Check both the "system" and "control" pressures with a k-jet pressure gauge.

Don't know how familiar you are with the k-jet, but there are a few general guidelines and tips here : https://www.ferrarichat.com/forum/threads/bosch-k-jet-cis-metering-plate-is-wide-open-at-idle-cause.641569/#post-147888021

 

It's been some time since I owned a 328 that I believe the fuel pump hopefully goes to the filter and then to the injection system so any debris would have been caught in the filter? I'm not a big fan of just replacing parts and throwing money at things but I would replace the accumulator it's now 45 plus years old is a diaphragm inside of it I believe it's less than 200 bucks which is nothing in the Ferrari World

 

Another thing to check is the "fuel frequency damper" it's kind of on top of the engine very plumbed into the small injector lines very easy to see easy to see there is an outlet nipple that would be squirting raw fuel if it was bad. As I recall these parts are in NLA but I'm sure there is some sort of aftermarket solution for these. There was even a guy on eBay that was taking a different damper and Machining the threads down for this application years ago for like a hundred bucks each

 

Have you checked the protection relay operation? An easy way to do that is to put you hand on the frequency valve and have an assistant start the car. You should hear, and feel it buzzing.
The protection relay sends power to the emissions ecu, WUR, auxiliary valve etc.
The relay is located in the right rear corner of the trunk/luggage area. Under the carpet is a metal panel held in by 4 10mm bolts. The relay is silver in color with a red top and a 10amp fuse in it. Check to see if the fuse is blown. If it's good, it still doesn't mean the relay isn't bad. You can jump the relay to test, but I can't remember from what pin to what pin..its a Porsche 928 part, about $300 bucks if I remember.

 

The system is utilizing two fuel pump relays. First one is operated during the starting and controlled by the safety switch on air flow meter. Once engine is started, and air flow plate is lifted off its base position, the fuel pump control is taken over by the second relay. If second relay is not working properly the engine will shut down in seconds. I'm suggesting to replace both relays.

 

The 328 only has 1 fuel pump relay.

 

It's not NLA: Bosch has resumed manufacturing which they presented during the the aniversary of the R5. (The turbo version had k-jet, and k-jets were originally desgined and made in France).

This being said, the WUR and the ditributor are easy to fix, and all the other parts have always been available (ebay is a good source). Adjusting the settings is the most difficult parts, hence the recommendation no to mess with the individual ports set screws or mix the springs.

 

On the 400i they are indeed two relays, one is for the cold start injector the other one is for the pumps. The cold start inkector may jave an additional pulsing relay (removed on the later cars).

If the car was fitted with a pseudo lambda system, it my have a frequency valve that "modulates" the control pressure. If it is faulty, it jas the same effect has a blocked WUR (Too much pressure).

 

Really?
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The 328 has 2 relays one to start and one to run

 

That is awesome that they have started making that frequency valve I remember when mine went bad it was leaking raw fuel directly onto the exhaust and when I replaced it I put a flame proof tube down and routed it so that it if it ever leaked again it wouldn't drip right onto the exhaust! I think it was only like $60 or $70 back then

 

I beg to disagree, the second one is controlled by the thermo time switch and activates the cold start injector.

Obviously it is not avtivated when the safety switch is locked but that's not the point. When the engine is hot, this relay is not activated

 

I beg to disagree, the second one is controlled by the thermo time switch and activates the cold start injector. It can remain active for 12 to 30 seconds (after cranking) depending on the type of thermo-time switch.

When the engine is hot, this relay is not activated.