308 Ignition problem - I think

sounds like your plug extenders. pull the plig wires and check for arching in side the extenders where they meet the spark plugs. they car go bad at the drop of a hat.

 

have you verified spark on all cylinders when the problem starts?

Why did you replace only one coil? Can you verify if you are dropping a cylinder bank?

 

Other things to check are the wire connections from the digiplexes to the engine, include the digiplex ground wires. Be sure that the wire harnesses are firmly attached to the units. It's been rec'd on Chat that one put long tie wraps around the units to insure that the connections remain in good contact. It's also been rec'd to add additional ground wires to the digiplexes. Also clean the bulkhead wire connections located between the oil cooler and expansion tank. There are 2 there which feed electricity from the digiplexes to the engine sensors. Disconnect and clean liberally with electrical contact cleaner.

It also seems odd that your idle remains high for so long and that performance deteriorates as it drops. There may be something amiss with your warm system as well.

Good luck and please let us know what it is when you find out.

 

I am very sorry to hear of your trouble and it is exactly the sort of tale that sours so many people on Ferrari's. Not meant as a criticisim but many of those problems could have been avoided by having a good inspection done prior to purchase. I hope your story convinces those that watch here before buying, learn from this.


It also sounds as though you have had a variety of significant running problems since you bought it, and you have thrown a lot of parts at it incurring a lot of expense and not a lot of satisfaction.

I would strongly suggest you not continue down that path, it will just get more expensive and not achieve any greater satisfaction. What you need to do is to find a Ferrari shop that has a good reputation and leave it in their capable hands. In the long run it will probably be cheaper, and insted of fearing that thing in your garage you can be out enjoying it.

I have noticed a large portion of the people here are from Texas and would be happy to help you find that shop. Go to the Texas section and ask their help, you will be happier in the long run.

 

Agree with this 110%. Do as he says..you will be much better off in the long run.

 

Hi Treverdog,

First of all, I too have been chasing a proverbial "zebra" for some time myself. If you are determined & patient, you *will* run this one down & love the car again.

Need to verify more data, baseline & when car is acting up. Timing light would be excellent step to insure you have spark on both banks/all plugs. Personally think a plug extender would show up prior to extended driving. Also would verify voltage at battery when car running improperly. This does sound electrical in nature, which these cars are notorious for.

Constructive advice: clean the rear harness grounds:

* Two on the rear upper frame rail above the LH gas tank. 13mm bolts, more forward one is challenging to access but possible.
* Clean coil ground wire (you probably already have). Ensure the bolt-on 45 degree connector is tight.
* Clean grounds at each rear compartment (FI ECU and digiplexes)
* There's also grounds at the taillights, but unlikely this is a problem if they work.
* Clean battery ground strap lower right rear of motor.
* Clean battery terminal connections (+/-) including the disconnect plug at the right front of car.

Beyond these: LH fenderwell conncetor, RH passenger footwell connector, Input connectors into digiplexes & FI ECU, FI ECU O-2 sensor relay.

If you're in TX, JRV is in Houston and Jim Lindsey in New Orleans is one of the finest people I have ever met.

Best,

Carl

PS See my post about FI oil temp switch (can cause running rich) but don't think this sounds like your problem.

 

Don't be scared of taking it to a ferrari specialist/dealer.

Give them clear instruction to DIAGNOSE only, and you can do the repairs yourself if you want..

To do many checks and rule out expensive items may take 3 or 4 hours, and it would be money well spent.

 

Consider checking for a restriction in your exhaust. I had the same problem on a '84 Mustang. Ran fine and then when it heated up, it would lose power. Had to replace the catalytic converter.