308 QV Misfire

* Congrats !!! nice job and thanks for posting what you found. I'm sure it will help others.

 

I apply a good amount of silicone grease around the wires and connectors at the digiplex to prevent further water infiltration.

 

good to hear you find the solution after all. Can you please put in a picture of this connectoor as i might have the same issue..

 

I,ve been reading about your problem and the replies. I just recently did some work on a customers car that someone had jumped the car backwards and killed both of the ignition modules. I got the modules repaired and the car ran great (initally). The car is a 1980 single cam car with only 11K miles. it had original plug wires and the plug wire seals were detoriated badly but the engine was running really good and I thought I was probably done with this job. I told the owner that he should change the plug seals because the first time he washes the car he is going to run into the problems that you are having with water getting into the holes. I changed the seals and by the way you dont need seals from the Ferrari yellow box which are about $25.00 dollars each. You can get the exact same thing form GT parts for about $11.00 each. Anyway I changed the seals and drove the car a little bit and all the sudden I had a dead cyl. I replaced the plug and it didnt fix the problem. I replaced the wire with an old wire and the cyl came back. You are probably wondering what is my point because you changed the wires recently. Dont take it for granted that your wires are good after a couple of years. This engine developes such heat that it can break down wires faster than you would think. I changed wires in my customers car and in mine. If you are a hands on kind of guy go to your basic parts house and buy a set of Accel plug wires PN 4440. About $35.00 or OEM for between 350 and 400 bucks. The Accel works great. You should be able to wash the engine anytime without any problems. I wash mine all the time , but rember you must remove the plug seals and extensions because the seal are not designed well enough to keep all water from getting into the holes. Just pull them off and blow them out with shop air. You said that you were reluctant to remove the dist. cap after you wash the engine. Dont be afraid. Pull the rubber boot back losten the three screws and pull the cap off. You are probably going to find some moisture in the cap. Blow it out with shop air untill it is dry. While you are there make sure that the center electrode is in good shape. This part can be replaced for about $15.00 The OEM cap is about $480.00. Check your cap, cracks are frequent. Gt parts has replacement caps for $195.00 Another thing you might look at is the kind of plugs that are installed. I use to not believe that the type of plugs would make much of a difference. I found that Ferrari had sold my customer Iridium plugs and I found it hard to believe that they would make any difference in how the car ran. It does.

 

Gents-having quickly scanned this topic/thread....

Things to think about: in general terms, when a car is running "ok" at idle, but deteriorates at higher RPMs/and-"OR LOAD"...
the faults, almost without fail, will be found in the secondary circuit of the ignition.
In electronic sysrtems which utilize a 50ish kv idle firing line, the demands-with respect to insulation of charge-on the post coil items are enormous.

If you "use oil", start with plugs. 2v injected cars, you know who you are....
the plug ends also will burn through...water always amplifies "voltage leaks"...
Wire end connections are notorious.
QV boot tops are less problematic then carb, and other earlier versions.
Wires are-as is shown in poster's pics-also a notorious problem area...

Caps, not so much, Dremel tool with wire brush head to the brass tips, ditto rotors..
Carbon tips with springs do require service/replacement regularly-hence the design.

Farther up the stream, and on the OTHER side...so to speak, are the coils, their leads, and the electronic triggers, boot heads, pins, and harnesses...while rare, are known to fail or cause problems.

ECUs almost NEVER cause intermittant problems-although rare-they do occur, but will manifest symptoms of other natures and varieties.

In summation:, typically start at 1 side of the tension circuit, and sytematically eliminate-through testing and component evaluation-a methodical and systematic evalation process..... while time consuming, it will GUARATEE a hi-degree ofcertainty in terms of a resolution at the end of a couple of hours of tracing.
Goood Luck!

 

On more conventional ignitions, a miss at high RPM can be caused by resistive connections in the primary circuit. Had that exact problem with a resistive ignition switch in my BMW 2002tii.