Help: Testarossa cold start normal engine idle ?

Congratulations on your new acquisition. Not so sure that idle is "normal"...?? Sounds to me as if the AFR is unbalanced between banks and causing the "hunting". I'm sure those more expert on the TR will be able to add their input?

You should have the KE-Jetronic system on your TR and from memory the idle control valves need checking, etc. With the Jetronic system I find you usually have to run through all the proper tests and checks to get it all running sweet.

 

Mine did this when I first bought it. In my case it was the mixture on bank 7 to 12 being slightly on the lean side and my idle control being out. Once it was set up correctly it's purrs.

 

That's it exactly - should "purr" when spot-on.

 

your cold start seems a bit off. I curious though. If you try to gently feather the gas to stabilize will she level off and settle down. On cold start if you rev her and don't ease her back down she will hunt. As your temp gauge move slightly you'll hear change over and level off. That is when the O2 sensors take over adjusting the mixture. So the questions are.

On cold start are your reving the engine and then letting her rpms drop by releasing the pedal

During the rpm hunt can you settle her down by feathering the gas and easing off the gas pedal.

If you are reving If you don't rev during cold start does she stay calm with much less hunting.

If all three questions are a yes. I think your ok. These cars can be a bit temperamental on cold start. When I started my car I would turn the key apply a little gas and when she fired she would rev almost like clearing her throat but I would ease her back down and she would idle ok until 02 sensors take over which is pretty much right about when the temp needle starts to move. If you can't settle her down then you probably have a slight mixture problem. These *****es don't like to play when they are not moist. Don't over do the warm up either. Soon as the O2 sensors take over your off

R

 

No.

No O2 sensors on a F113B engine late euro TR (KE-Jet without Lambda).

Could just be the mixtures being set too lean as the others suggested, but that's also a symptom of the protection relay system not working and then a Mechanic wrongly tweaking the mixtures in that condition (i.e., with a non-working protection relay system). Warm-running can be OKish (because that's the running condition that it was wrongly tweaked up in), but cold-running will be much too lean as the EHAs won't be adding cold-running enrichment as they should (and that Mechanic wouldn't be the best judge of what's "normal" or not ). I'd rule the protection relay system in or out first (which is fairly easily done just using a voltmeter) -- try a search on "protection relay red wire" for prior threads (for example, post #12 here: http://www.ferrarichat.com/forum/boxers-tr-m/270367-tr-air-metering-device-idleing-problems-2.html)

 

Like Steve said, this is not normal. Your TR should start and purr hot or cold with the idle hovering adorn 1,000 RPM.

Playing with the Air/Fuel mixture adjustment is the low hanging fruit. When set up correctly, the engine is telling you something else is wrong.

Nobody mentioned a stuck cold start injectors? They are easy to get to. Perhaps pull them to see if one is stuck/clogged?

 

I have just set balance with k-jetronic this year, with idle and high rpm and check them afterwards. I found that sometimes when started stone cold, I get five or six rpm waves, but then idle sets good. Most of the time starts just like should.
with my car there is very small diffrence between vacuums that was very difficult to get out, as K-jet seems to alter little bit after some drive.

btw, only accurate tool for TR is manometer
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if the cold start injector is not working right you may have trouble to start. this cold start injector is only in use during starting. so this to check would be a waste of time

 

Issue with design is, that K-jetronic was made to work as single unit, air and so on is easy to set, but I think that soon after these cars had left from factory, WUR does not work exactly same manner and those parts where never design to work as a pair, there are tolerance and that is why in extreme (cold engine) end of pressure there are no exactly similar wur units. Add natural corrosion and you get this little bit different mixture, that with engine like this, makes them accelerate from one side and moves other side air measure plate to wave idle.