1979 308GT4 - mostly a weekend driver When I start the car from dead cold, my idle is low and my red "G" light is illuminated. Without help from the gas pedal, it will sometimes stall. It idles around 500RPMs, but if I use the gas pedal to push the revs north of 1,000, the light goes out. However, letting off the pedal, the revs will drop right back down low. My solution to this problem is to just hold the revs up (between 800-1000) for a minute or two until things are good and circulated. After that point, she'll sit and warm up on her own no problem, but the idle does seem to still be low. When returning home after a drive, it idles at 700RPM, so I know it's set correctly. 1) Is the low idle at startup common in the older cars? And, 2) Is it just a byproduct of the cold, thick(er) oil "lugging" the engine down by a couple hundred RPMs? Thanks in advance - Aaron
The red "G" is the alternator light. (the "g" dating back to when cars had generators) When you rev it up, enough voltage is supplied to activate the regulator, so don't worry about that. It just sounds like your car might like a little bit of choke (1/4 pull) or the cold start cam isn't adjusted properly. Or, if you add a little choke and it hates it, you've already figured out the fix. Nothing wrong with sitting in a Ferrari for a few moments of reflection in the morning! Of course, being in AZ my car doesn't need the choke or the cold start cam. So who am I to say!
Regarding the choke... That's one thing I know nothing about. This car is my first carbed car (ever), and when I was "going over things" with the previous owner at delivery, he referenced that choke lever on the center console. What I got out of it was that it's something I'd never need to touch. Perhaps I should do some experimenting?
I would go alone with the above post on checking the fast idle cam. Remove the air filter, the cam is centered between the carbs its about the size of a 50 cent piece, there is a screw on an arm that rests on the side of the cam that you can adjust the fast idle with. You wouldn't need to turn in the screw much to bring the cold idle up to 1000 or so rpm. Using the choke only won't really speed up the rpms it just adds more fuel, the cam has to open the throttle plates slightly along with that for more air too. IMHO it's not a very good choke system you can dump at lot of fuel in the engine and wash the cylinder walls easily. The old owner is correct you shouldn't have to use the choke they were good for flooding the engine and that's about it, HaHa. Again I would check the fast idle cam first. I owned 2 carb cars in Montana and never touched the choke on either. Hope that helps. Regards, Vern
700 RPM is too low for fully warm idle -- should be more like 1000 RPM. Most carb 308 Owners disable the fast idle cam mechanism and use the acc. pedal to manually add enrichment via the acc. pumps (and a little extra air) during cold-running as needed (rather than using the choke).
Interesting... I'll definitely investigate the cam mechanism for curiosity's sake, if nothing else. It sounds like my idle is too low, though. I wonder if that wasn't perhaps something that was done to optimize the car's chances of passing CA smog testing?
I would say your warm idle is a bit slow. As far as your car's cold behavior - I've adjusted the air fuel mixture, idle speed and synchronized my carbs (today my mechanic said the car runs beautifully - new rear brake rotors/pads/parking brake adjustment) but exhibits the same behavior on a cold start. The fast idle cam is disabled. Just add some throttle during warm up and enjoy the drive. I've noticed that it's not as bad the more often I drive it...
Steve - is there a 'best' way to disable the fast idle cam? Mine was disabled for the first 6 years of ownership but a couple of years back when the guys at garage tweaked the carbs they inadvertently enabled the fast idle cam. From other posts here it looks like there is some kind of screw that can be used to adjust the setting. Failing any 'best' way I will get the air filter off and work it out myself. I find the fast idle extremely irritating, I much prefer to manage the idle with my right foot when the car is not quite up to temperatue. Practically every 308 owner is terrified of the choke - I was advised by Terry Hoyle (well respected engine builder & Ferrari restorer in the UK) via a third party to forget the 3 pumps of the throttle method to fire the car up but to use the choke. I still tend to use the 3 pumps method but at the risk of arguing (on a subject that I am not an expert on) with every Ferrari mechanic & every 308 owner - the choke isn't there for decoration and I would not be suprised if there were advantages in using it.
It will be very obvious to you once you get the air box off -- it's a straight-forward mechanism. Just back the adjustment screw (that would normally touch on the edge of the cam plate when cold and hold the throttle linkage more open) outwards until it doesn't touch the cam plate at all regardless of the cam plate's angular position. The problem with the DCNF choke isn't that it doesn't work well when it's working properly, it's that there is a small likelihood that a spool inside one of the carbs can stay stuck partially open (adding extra fuel) even if the lever in the passenger compartment is returned to the fully closed position.
Check your idle jet sometime they can get clog with a small particle, blow it out with a compress air or with a carb cleaner.
Thanks for the info. At the risk of digging myself in real deep, if the choke is working correctly it must be a better way to start a 308 than the 3 pumps of the throttle then turn the key process? The 3 pumps method is simply dumping fuel in as opposed to the choke that is enriching the mixture. The dumping in of fuel is what will wash the cylinder walls?
I don't draw such a distinction between the two methods (although I found just a couple of half-squirts to be plenty in a mild climate). I think you are assigning too much sophistication to the DCNF choke operation -- both the acc pump and the choke device add raw liquid fuel in a fairly crude manner. Not saying that using the choke as intended isn't a perfectly reasonable thing to do. It got more of a taboo in the US on the later cat-equipped cars where, in the rare case of a choke spool failing to close, the penalty was overheating a cat, and maybe a fire, rather than just the annoyance of fouling a plug.
When I start my car, I depress the pedal halfway and crank. While it's cranking, it'll give it a couple half-pumps. I have always wondered why my car sometimes takes so long to get turned over when cold - perhaps this is my problem? Should I be pumping 3 times (all the way to the floor) and then turning the key with no throttle applied?
You should do the squirting first (regardless of the amount), then hold it partially open and crank the starter (assuming that the fuel bowls are full from recent use or that you waited for them to fill before squirting).
I was told to never use the choke on warm up on my old 78 by 2 independants and 1 dealer. Is that still the case?
Like everything else...it's a debate. When I say "use choke" I mean pull back the lever maybe a 1/4 inch. Others may be thinking yank it all the way back. If properly maintained (like everything else on a Ferrari) it's safe to use. Even then it will only be used for a minute at most before it can be shut completely off. This is just my car. Of course, my car is setup for Phoenix smog testing which means it's a little leaner then you folks with a richer stock set up for no smog testing. A higher, steady idle when cold is better then revving it up and down to warm it up. If you're using the proper amount of choke, raw fuel won't be DUMPED into the barrels because the fuel will get burned! The higher rpm's keeps oil pressure up as well. Like everything else, proper maintenance, proper use. And yes, when warm never choke, never pump. Otherwise a good backfire and an embarrasing cloud of white smoke out of the right scoop! Don't ask how I know....
At 1 week, there's probably still enough fuel in the bowls that it doesn't matter much, but it wouldn't hurt to let the fuel pump run for a few seconds before doing the squirting and then the cranking. I was more trying to convey that after ~2 months of disuse you should definitely let the bowls fill before squirting; whereas, if just overnight, it's OK to just squirt and turn the key directly from "off" to "crank".
