5 Things Learned About the 456GT

Relatively new here. Took delivery of my first F-car June 2012: a 1995 456GT, 6 spd, 16K miles. I've learned a ton from F-chat and won’t try to thank everyone individually who’s helped, some directly and others by posting their info, but many thanks to all concerned.

Thought I’d share some more things I've discovered about the 456 and maybe get some feedback on details I may be missing. Already gave my 2 cents on spare tire, cooling, etc. Hope I’m not giving too many details. I think it’s good to know how to do something, but better to know why to do something.

1. Check Engine Light/ CEL:

My first CEL lit when I took the previous SoCal car in for Texas emissions testing. Carfax showed it had never failed a Cal test. A CEL actually lit during the Texas tailpipe testing but passed with only about 1/10th to 1/20th of allowable HC, CO & NOx. So, I suspected there wasn't much seriously wrong. Learned to clear the codes, and extinguish the CEL with the battery disconnect, but the CEL's, each side, kept coming back. Seemingly randomly.

Eventually learned to read the codes (see the F355 WSM; the downloadable 456 WSM doesn't have that info). Anyway, I got several codes. Recently, I was getting 1111 (hot wire flow meter) and 1211 (the usual Lambda regulation code I see all the time).

It seems, the 1995 456GT M2.7 ECU (all other 456’s have M5.2) stores a code but doesn't leave the CEL on if there are one or more errors for < .5 seconds. It lights for 4 sec and goes out. More than .5 sec and the CEL stays on. Since I could go quite a ways w/o a CEL, I was pretty sure it wasn't a failed component. I suspected random misfires and could hear and feel them.

(One-half second doesn't seem like much time but look at how the V-12 fires: about 8 times/sec at idle per cylinder; that’s 100 power-strokes per sec at 1000 RPM and a staggering 730 fires/sec at redline when you add up all 12 cylinders. Like a V-6 doing 14,600 rpm or a V-8 @ 10,950. So, you have to have about 4 misfires at idle to light a CEL, but you need many more misfires to get a CEL at high RPM. At least, that’s what I’m guessing)

Since the CEL lit mostly at idle, significant misfires seemed to be the problem. But why? Also, I listened for injector misses with a stethoscope and each sounded great, like a fast running Rolex; 8 ticks per sec. Try it.

Early on, I inspected the connectors to various components and they looked great and corrosion-free, including the million pins coming off the ECU. Looks are deceiving, so I eventually tried an electrical contact clearer and a Mass Airflow Sensor (MAS, or as most folks call it for reasons that elude me, MAF) cleaner. One CEL no longer lit, but I still was getting a MAS error, so I tried swapping them from one side to the other to see if the error followed the MAS. Only this time, I doused the connections (as many as I could easily open) with WD-40.

Voila, as if by magic, no misfires and no CEL’s. Now, I have to admit, I haven’t been killing myself to fix this problem as the car never ran poorly, but it has been bugging me for 6 months, not knowing when a CEL might come on. I've read of others switching components and having their CEL problem go away (concluding it was just the connection) but I haven’t heard anyone recommend the humble WD-40 (I've heard WD stands for Water Displacement, which doesn't really apply here). And, I’m not even sure the WD was the cure. Just citing the cause and effect.

I've read some testimonials about Dave Helms’ Gold Connectors. Some say although their car ran good before, it feels different after the swap; like it runs better than ever and like it never has before. I'd say the same with my experience and recommend spraying the connections as regular maintenance. Also, I don't think Helms' harness is available for the 456. I’m now a believer that our ECU harnesses are a critical component that need attention.

Okay, sorry to drone on about CEL’s. The next 4 things are pretty obvious but may be worth mentioning.

2. Battery Disconnect Switch/ BDS:

Here’s some empirical data on using the BDS. We were gone for 2 months. I used the BDS on the F and left our Jag with a bigger battery with the alarm off and unlocked, bat connected. On return, F bat voltage was 12.64. Jag voltage was 11.60. Jag bat was fine after charging. Moral: The BDS is as effective as a trickle charger.

One more thing, I've heard disagreement about whether the BDS clear codes. It does, even for short disconnects on the 2.7 ECU.

2a. I've also started using Sta-Bil Ethanol gas treatment in the tank, based on advice gleaned on F-chat, since I’m storing for up to 2 months. I’ve always used Shell 93 and never had an ethanol problem, but thought the Sta-Bil is cheap insurance.

3. Radio Reset:

Everyone probably knows this. Or not. I didn't, but it’s in the Hi-Fi System Manual. There’s a tiny reset button on the radio near the M. Scan button. (See pic below.) One of those resets you have to use a toothpick or ballpoint pen on. Even with the manual, I couldn't find it with old eyes, but it’s there. Only had to use it once, and I was suspecting a CD changer failure before I found it. Trunk CD changer wouldn't work. Works fine after a reset. Some have suggested sending the CD changer to Sony for repair when this happened. Always try the reset. Worked for me. Also, the manual says to reset on “first use”, whatever that means. Assume after a bat disconnect, although I've never had to.

4. Cupholder:

Have read various solutions. I hate the things myself. Recalling the time I was just leaving a gas station, starting a 200 mile drive home with nice fountain Coke in my Corvette’s factory cupholder, when some b!#$h pulled out in front of me. I never got all the Coke syrup out of the creases in the Corvette’s cheap plastic console.

But…..Wife found this contraption at Autozone (see pic) and, I must confess, it’s handy on long trips. Pull it out when you don’t need it.

5. Ashtray Lid:

I see the ashtray lid open a lot in pics of 456’s for sale. Mine won’t stay down for long either. As a temp fix, I've been using the caveman approach. Put a rock on it….or…. actually, under it, in the form of 4 zinc stick-on weights. (See cupholder pic.) It mostly stays down now.

Not real proud of my “ashtray-lid-engineering” prowess. Anybody got a better idea for the ashtray lid or anything else?

Regards……Mark in Houston

PS….When I get frustrated with the 456, I just watch this video…

[ame=http://www.youtube.com/watch?v=MGZ17HTXmtw&feature=player_embedded]Old Top Gear - Ferrari Special - YouTube[/ame]
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Thanks Guys:

MAS/MAF. I've seen both, but mostly MAF. Anything’s better than “variable-resistance, heated-wire, air-mass-flow transducer” or as I called it when the CEL came on: the GDMAS. From now on, I’ll use General Motors’ acronym of MAF sensor for the Mass Airflow Sensor (wouldn't that be MAS?), but I’ll also reserve the right to heretoafter refer to GM as GFM.

Taz- Right, I left out the Relearn part after using the BDS (that’s in the manual and well documented on F-chat). Idle for about 10 minutes, followed by some slow driving, followed by a few seconds of near WOT. (Damn, I hate that last part! The last part is not in the manual.) And, I agree. I don't think the M2.7 cares too much.

Also, the contact cleaner didn't work for me. I used Q-tips and contact cleaner (liberally). Also used Techron Concentrate in the tank, cleaned the TB and both sides of the butterfly and the MAF’s, to no avail. It’s only my best guess that it was the WD-40 what stopped the CEL’s….

Also, didn't know Dave has the Gold Connecters for the 456. No mention on SRI website. Has anybody tried them on the M2.7? Mr. V?

Hoses yes, and will get those at some point. Mine were recently replaced with the updated F hoses; the white-stripe variety.

Barry- That was my conclusion. Idle trips the CEL because the M2.7 is time dependent, not error dependent. I’m not making any claims here, but, as Taz said, what could WD-40 hurt.

More weights on the ashtray lid?… I’m near my space limit with Zn… Anybody got any Nobelium???? Regards...Mark

PPS.... The 456 stuff on the Top Gear video doesn't start until about 20 minutes in....

 

Dale- My wife rides in it... Does that count?

Rick- Glad I mentioned it then. It just struck me that that tiny button would never be found...

John- W???

Taz- I'm sure you could find some D U in your neck of the woods... Love that part of the world, Valley of Fire, near Trinity Site, and of course White Sands. We usually stay in Columbus so we can venture into Old Mexico...

Barry, et al- try some Jimi... even if it skips, you'll hardly notice... does encourage you to put your foot in it though...

Regards....Mark
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Thanks Guys:

Why didn't somebody tell me (or anyone else) that 6 months ago? Will do...

W = Tungsten... You guys got me...I'll start saving my burned out incandescents...

The only reason I used nobelium is I thought "plutonium" might get me in trouble...Oh crap, I said it....