Rough cold start and inaccurate tachometer

hello phantomferrari

would be great if you could fill out your profile and also introduce yourself a little
this will help you and also all members here
thanks

 

What engine family? F113A or F113B?

 

Fill out your profile. Corroded dist cap does not explain why she runs fine once warm. A minor rough condition is not out of the norm but I mean a minor rough or should I say slight hunting. Cold start injectors thro some extra fuel so she is in a very rich condition. Why she won't exceed 3000 rpm is baffling to me. Once again those fly wheel sensors would still give you trouble even when warm. Could be that the mixture is off if she is really running rough when cold. Once the temp needle moves a bit the o2 sensors take over and control the mixture. I would eliminate the o2 sensors as well from the equation. If they where mixed up she would also run like ****. Ignition wires and or plugs would still give issue even when warm as well. Would love to hear her when she is cold. They don't like being cold and being so rich could lead to difficulty starting if you continue to shut her down and restart when cold. They also don't like that. Steve should chime in for some further diagnosis. Cleaning the cap and corrosion is a good idea since your in there.

R

 

Nothing wrong with making sure that the ignition system is working well first -- and you should do that first (but a timing light should be able to let you confirm/deny that before buying a lot of expensive parts). Once you are happy with the ignition system working OK (and if you still have the cold-starting difficulty), I'd suggest that you start on the injection side with checking that the protection relay is working and supplying +12V to run the KE-Jet injection ECUs as described here:

http://www.ferrarichat.com/forum/138953899-post18.html

One "problem" with the Bosch CIS injection system is that it gets tweaked up when warm -- so it often happens that something fails, but the Mechanic wrongly starts tweaking things before actually figuring out what has failed. This can make warm-running seem quasi-OKish (since a bunch of stuff was tweaked to make it OKish), but cold-starting and cold-running well requires everything to be working correctly (not just warm-running being OKish). Good Hunting!

 

Have you confirmed both sides of the ignition are working/firing. The TR will run with only one half firing....not well, but run. It also sounds like you have two different problems, the engine and probably the tach. There is a small electronic board behind the tach. Mine would fail to register proper RPM's after about 30 minutes of driving. Bad circuit board, $200 fix from a good speedo shop.

 

FYI, I had tach underreporting problems a little while ago - this thread could help you:

http://www.ferrarichat.com/forum/boxers-tr-m/518734-tr-tach-under-reporting-sticking.html

 

Ignition wires I would get from Scuderia Rampante. He has the Taylor 7mm wires. He will make you a set. The factory wires even brand new wires are crap. Spend your money wisely.

R

 

Interesting, I did not know this. SR makes a good product, only makes sense that he offers a superior set of wires.