Ferrari 328 Power Issue

Just a guess for something to look at. Could be you are losing spark on one bank.

 

Is this a US version 328? If the power loss is roughish and unsmooth, verify if the frequency valve is vibrating/buzzing or not (by touching it) -- it should vibrate/buzz whenever the engine is running or the starter motor cranking (i.e., whenever the fuel pump is running -- so you can also just unplug the safety switch and turn the key "on"). If it doesn't = strong sign something is wrong with the operation of the Protection Relay. If a bank of ignition is lost, the power is down, but the engine should still run smoothly. Please describe your power loss as being rough or smooth.

 

Sounds like fueling to me...

 

I had GTSi that had similar issue. Was a wet clogged fuel filter.

 

On the 328's your symptoms are electrical. so start there. check fuses - fuel pump fuse 1st.

then on the rear right side - The passengers side of the trunk undo the carpet on the bottom ( velcro) and undo the 13 mm screws and check that the frequency relay is intact and that the fuse there is ok. this fuse and relay hang upside down and from time to time can work lose.

if that is not the issue, check for the connectors behind the fuse block ( wiggle them while the car is running ... see if that makes a change finally in the footboard on passengers side there are two main connectors that sometimes the wiring burns out - usually on the fuel pump side. if all your electrical connections are good, THEN start looking at pumps injectors etc.

If its not electrical - check vacuum lines - they can get holes, that only show up when the engine is warm, causing pressure issues... un metered air etc. I think folks are way too fast to go right to fuel delivery issues.. when most likely its electrical.

these cars are getting old, and wiring is brittle, so heating and cooling - change of ambient temps can cause issues...

hope that helps.

 

My 89 did the same thing and it was the frequency valve relay like Steve mentions. Check for the buzzing or just unplug it to see if it is working. You can test it with a 12v jump to see if the relay is working. I ended up buying a Porsche part with updated fuse and it worked great and only $90.

 

I just had same issue with mine and it was indeed the fuel pump relay. Super cheap and easy to fix.


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Well, the shop also said it was fuel injectors.

 

Don't buy a new Protection Relay unless you confirm that the frequency valve is not vibrating/buzzing -- even then, you should first check its 10A fuse, too, as that fuse is supposed to blow if the alternator goes haywire -- hence the name (Overvoltage) Protection Relay.

Since you report that the power loss is "smooth", you should confirm/deny if spark is occurring on both banks using a timing light or spark tester IMO.

 

That's exactly what happened to mine a while back. Car ran smoothly with no power and low idle RPM. turned out to be a loose HT cable connector that fixes into the coil on one bank had come unclipped.

 

I don't know USA models enough but the problem couldn't be the injectors as K-Jetronic is a CIS so the fuel dose is made by the fuel distributor plate. When you hear your mechanic that tells you "the problem could be the injectors" means you got the wrong mechanic. Very likely you lost electric power to one of two banks spark plugs or there is an electric problem to the fuel pump. I don't know anything about the frequency valve as there isn't on the italian cars.

Ciao

 

If you've driven any distance like that then you also need to check that the Copper terminal inside the coil that the lead pushes into isn't toast.
Re the seal, these have a circular spring that holds the lip against the camshaft. Care must be taken to ensure this spring doesn't become dislodged when inserting the seal. Otherwise it will leak.....

 

Leaking cam seals is kind of a "thing" in the 308/328 world. unless its a huge leak you can usually live with it.
glad you found the culprit.

 

There is a trick to install that seal.