Technical is butterfly supposed to open

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Technical is butterfly supposed to open

qaz83885

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Location
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hi
2007 doblo . on my 1.4 doblo/punto engine with van stationary , engine at 1000 - 2000 rpm, the butterfly is shut with engine hot is this normal [but i cant see it if i operate the throttle quickly]
thanks anyone
 
Model
doblo
Year
2007
Mileage
2
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no problem yet .
not at idle but at driving speed. i need to know pls if it opens
anyone know?
thanks
 
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sorry if made it to complicated but i just want to know is the butterfly supposed to open. i mean dosent it need air to run, so how can it get air with the butterfly shut?

thanks anyone
 
and if so when
thanks
correction: 2000 to 3000 rpm [driving speed]
 
It must be open while driving (while you demand it by gas pedal), how much, you can see via OBD2 (Fiat specific soft, FES, MES, AlfaOBD).
"Drive by wire" just mimics older cars with mechanical linkage from accelerator pedal to flap/butterfly. That's it.

It's never completely shut at idle (small gap is intentional).

What's the point of this thread if you don't have any problem with the car? :rolleyes:
 
If throttle butterfly isn't opening when it should your vehicle wouldn't move.

Please do not open multiple threads with the same question.
 
the problem is that i don't/didn't understand why it did not open. [i still don't know for sure]

it seems you may be saying that "it opens if the pedal demands it". Can someone please clarify this, thanks
 
ok, it does move very well [good], and butterfly does not open as i can see when stationary. so far no one has told me that it opens at any other time.
i seem to be getting some cryptic answers here so i made another thread .
but i'm sure the people replying mean well . thanks
 
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The throttle butterfly opens in relation to the demand for power from the driver.

The opening of the throttle butterfly controls the engine power by controlling how much air goes in engine

Please do not start extra thread on same question if you don't like the replies you get, if other people have something to add they will post on the thread.
 
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The throttle butterfly opens in relation to the demand for power from the driver.

The opening of the throttle butterfly controls the engine power by controlling how much air goes in engine

Please do not start extra thread on same question if you don't like the replies you get, if other people have something to add they will post on the thread.
the problem is that i don't/didn't understand why it did not open. [i still don't know for sure]

it seems you may be saying that "it opens if the pedal demands it". Can someone please clarify this, thanks
thanks for the more straightforward answer , guess that clears it up as i really can't spend any more on this . i will assume it opens only when only when one accelerates as it doesn't open at 2000 - 3000 rpm stationary. at that rpm it must be running on magic in stead of air as the opening is so small
 
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So you didn't bother to read posted links. There is information about this.
Air for idle comes from 2 sources (throttle gap and small breather hose, it acts like a bypass for throttle). No "magic" here at all.
And for idle, one of the 2 is enough to keep engine running properly.

Still your thread is pointless. Are you just curious about engine management/control strategy or what? Ask Magneti-Marelli (e-mail them).
Told you: use OBD2, so you can log data (make a plot/graph), when the flap is open or not. Easiest solution.
Or remove the air filter box and install a camera (dashcam) under the hood/bonnet. And make a test drive.
 
i assure you my thread is not pointless [for the reason i stated].

you seem to have given me the info in ur last msg that explains every thing [second and third line]. so thanks.

I'm curious but for very good reason as I was formerly a mechanic by trade . i followed the links, the one with mention of polishing, and strip down was very interesting but annoyingly some detail was incomprehensible

obd2 ive never heard of but the page suggested it was perhaps ecu related

the small breather hose on mine is split so perhaps its the cause of engine running fast [only] when cold . i was trying to discover [here], so i could find on ebay, what the 2 hoses were called, but only found numbers at the link. [the smaller diam. one that runs from air filter box downwards to, maybe, the manifold

excellent idea ...i'll un-stick the dash cam from the screen and watch it that way
[any more info appreciated]

thanks.
 
Mechanic? Car/automotive mechanic? Come on pal...
You've never heard of ODB2 diagnostics (you know, you stick the plug into car and other end, USB, to the laptop)...?

Also, increased RPM while cold is a common thing in most cars, in the era of carburetors it was called "choke" (it was manual linkage, you had to pull it to start cold car, do you remember?). Nowadays it's automatic. Cold Grande has 1200-ish RPM's or so. Normal behavior.

Breather hoses are part of the PCV system (crankcase ventilation). It has nothing (just a tiny bit, but not in this case) to do with engine RPM.

I repeat the question: is there any real problem with your car, or you just F-around (...and find out)?
 
i'm old, i owned a garage in late 70's. no injection systems were common here, then

yes i may well know more than u probably about carbs, don't assume i know nothing, it sounds really rubbish!

my doblo ticks over cold at exactly 1100 rpm when cold, making it too fast to drive in side streets in third gear. interesting that the grande idles at 1200, how can u drive it without using a low gear????.

for last time i'll explain then ...i want to know basics of how it works before i go charging in with a spanner. surely u can appreciate that, i dont want to contact manufactures, i'm not f****** about, and I'm not the idiot u seem to think
 
Read slowly. I said it's about 1200 rpm (exact number does NOT matter) when cold, right after cold start. Then it drops towards the 700.

You are the problem. Just beacuse you are older, you refuse to take ANY advice from others.
I gave you strictly technical info (about using OBD2, idle air and so on). ECU program decides how much butterfly opens - that's it.
Besides that, this is still a normal car, I mean, it's a machine. You start with basics (just like in 70's cars).

Your approach is completely wrong, for now. You are focused on wrong area of the car. Leave the throttle alone. Now. Forget about it.
Do mechanical basic checks if something is "ticking" (if I understand your post right).
Timing, compression, spark plugs, valve clearance/lash (shims) if it's 8V (you didn't specify which "1,4" you own, there are about 5 versions!), exhaust manifold leaks (studs are prone to cracking, manifolds are warping), worn VVT wheel can also "tick" when cold.

This is a perfect car that combines classical mechanics with modern layer of electronics (OBD2, modules connected with CAN network etc.).
You can learn "new" stuff while servicing it. But be patient (study Internet, there is plenty of info of how to do things).

Otherwise that simple Fiat can punish you badly. For example, even seasoned professional mechanics do timing belt wrong on these (they create infamous P0016 fault code using proper timing tools!) sometimes. Watch out. Fiat will correct your attitude if you step out.
 
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you continue to get things wrong about me and what i hope to get from this forum. you keep twisting what i say to suit your own agenda

the first thing is that i have tried to absorb all advice offered here, some has been useful. but with people like you who think obviously think they are very important its not worth the hassle. many forums attract people like you, which is sad

I have no idea what " ticking" refers to.

please DO NOT comment on any of my posts in the future
 
Then explain what's your "problem" with the car. Why are you still so fixated about throttle? What's the thought process / your secret agenda.
Butterfly issues are 100% clear now (if you follow advice: data logs via OBD2 or primitive methods like recording a video). Period.
So far, you are completely clueless about "modern" cars like Grande Punto (18-19 years old model). Straight fact (no judgement, no feelings).
You look like an amateur/hobbyist - not real, professional mechanic. That's the impression (the WAY you approach unknown).
That's OK if you will to learn (we all learn here etc.). Just don't be stubborn like that (it's a bit counterproductive).

My posts may look "offensive" (due to language barrier/translation), but they are not (you'll understand this in the future if you stick around here longer).

PS
Tell us, why your business failed in the 70's? That will tell a lot about your current problems... Wanna bet? You can flip it into business advise for us youngsters.
Tip: use "agree & amplify" technique, instead being upset. For example.
Maybe no one tested/challenged you in years (decades). Now it is the time. Your final exam (automotive, mechanics and beyond). It's the way you handle things.
 
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I too am an old fart starting out with 60's and 70's era machinery etc., Progressing onwards into the *electronic"era and nowadays, computers, dam computers, Dam bloody computers on 4 ( even 2, and many more ) wheels......

Sounds as if you need to "read up" on Vehicle stuff since the 90's, it even s bit earlier.

Your mechanical understanding will stand you in good stead, as well as electrical. Remember the early alternaters, give a modern *kid* a 3 bobbin Dynamo control box ( rb340 ? ) And he will not have a clue ( just like you with obd, ECU interrogation etc... ) But I am sure he is capable of finding out, just like you.

Remember the ds and id's, I bet you ran away from them, I ran towards them......

So bite the bullet, get some basic modern diagnostics ( they only "suggest" the problem, believe me ! ) , Read some books ( remember them ? ) , Read vehicle specific books ( not Haynes ) and embrace modern computer control, or run away from it and pay......thru the nose .

No malice, no umbrage, it's up to you.

At least "gen up".......
Do more research......act like a sponge......
 
i agree i do need to study the computer side of things, am very interested to know your views on Haynes , ive owned many of them over the years and am just about to buy the digital version [theres no hard copy] for my doblo [£23]
thanks
 
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