Motorul trepideaza mai tare decat ar trebui in ralanti

[ender]

Am si eu o mica problema:

De la o vreme se simpe cind sunt oprit in trafic un mic tremurici , cred ca de la motor, similar cu cel ce se simte in momentul cind tragi de volan si intra servo la relanti.

Aveti ideie de la ce este vibratia?

[voinea]

Cred ca vorbesti de cunoscutul "Slow-down Shudder". Patit si eu si remediat cu VAG-COM. ca sa fiu mai precis o sa-ti dau explicatia in engleza:

Solving the "Slow-down Shudder" and Other Shudder Issues - Recalibrating the Fuel Quantity at Idle - A VW specific scan tool such as VAG-COM is required for this procedure. With the engine warmed up and running at idle in neutral with all major accessories such as air conditioning turned off, connect the scan tool cable and start the scan tool software. Select engine control module. "Login" using 12233 as the access code. Select "adaptation" and go to adaptation block 1. Note that the display shows a default adaptation value of 32768 and shows the amount of fuel being delivered in milligrams per stroke. (If it does not show this, you are either on the wrong screen, or you have an older ECU that differs slightly - see next paragraph.) The specification range for reported fuel delivery at idle is 2.2 to 9.0 mg/stroke and they normally run best between 3.0 and 5.0 mg/stroke (highly tuned non-stock engines may differ - you'll have to experiment in that case). If you see a number smaller than your desired range, enter an adaptation number that is slightly smaller (say 100 units smaller than where it is now) and "test", to see the effect. Adjust the adaptation number up or down as required to achieve a reported fuel injection quantity as close as possible to your target. It is only possible to adjust within a very limited range using this method but experience has found that it doesn't take much change to make a big effect in the shuddering. Once you get a proper setting, "save" it.

Note for '96 Passat and possibly other older ECU variations: The adaptation numbers are in a different range, and you won't be able to get feedback on what you are doing on the same screen. You'll have to flip between "measuring blocks" group 1 and "adaptation" block 1 to see what's going on.

Physical adjustment of the upper section of the pump is also possible to recalibrate the fuel quantity but it is strongly recommended that the adaptation method be used first. The physical adjustment method requires the use of a special tool to loosen the special security bolt on the injection pump, then the other 3 bolts that secure the top 2 sections of the pump to the housing (you can leave the upper cover in place - it's movement at the second split that you are after). In addition, this method still requires the use of VAG-COM to ensure that the injection quantity remains in the proper range. THIS METHOD IS NOT RECOMMENDED FOR BEGINNERS. It is a "last resort" to solve an engine that persists in not running correctly despite all other attempts, and which has had major surgery performed on the injector pump, and even then, ONLY if a VAG-COM check finds that the pump is out of OEM specifications (2.2 to 9.0 mg/stroke at warm idle in neutral with all accessories off). CAUTION: Improper physical adjustment of the pump is capable of causing an "engine run-away" condition which will result in severe engine damage. ALWAYS ensure that if a physical adjustment is done, that the adaptation setting for group 1 is at factory default and that after completion of all work, the reported quantity at idle is within factory specifications

Motorul tau e cam acelasi cu al meu si treaba asta exact e si in functie de temperatura (acum a inceput sa fie mai frig), partea buna e ca daca asta e tremuratul de care zici tu se rezolva

[eugend]

si ca sa completez cu ce a zis Andi si ceea ce am facut si io aseara.

Cu cat cantitatea injectata este mai mica o sa ai un raspuns mai bun al pedalei de acceleratie.

Pt a rezonva problema ta trebuie sa cresti putin valoarea adica sa ajungi undeva la 4,5-5,0mg/R.

Ceea ce nu stiu eu este daca se manifesta schimbari asupra consumului.

[eugend]

uite aici citatul din andi

Cu grupul 1 este o cu totul alta poveste.

De fapt asa "calibrezi" cantitatea injectata la ralanti. ECU nu modifica cantitatea de motorina injectata pentru ca s-ar modifica automat si turatia de ralanti, ci isi "noteaza" ceea ce inseamna in valori reala cat injecteaza el la ralanti si respectiv "calibrezi" curba de injectie (la ralanti ECU injecteaza aproximativ la fel la toate motoarele de acelasi fel pentru acelasi ralanti fixat).

Tu de fapt ai "saracit" amestecul spunandu-i ca de fapt el in loc de 2.4 el injecteaza 3.3 mg/R pentru o valoare reala de 2.4 mg/R (sa presupunem ca initial era bine calibrat). Cand in functie de curba lui de injectie si de inputul tau din pedala, ECU ar trebui sa injecteze 33mg/R va injecta in loc 24 mg/R. Asa scapi de fum (mai putin combustibil injectat - smoke map-ul translatat in jos), scapi de vibratiile in cazul incetinirii cu masina scoasa din viteza (slowdown shudder) dar iti scade de asemeni si raspunsul la acceleratie

[Andi TDI]

@ender: Problema ta apare dupa ce ai oprit sau in timp ce incetinesti ??

[ender]

Scuze pt raspunsul tirziu ...

Apate in momentul in care sunt oprit, cutia de viteze pe liber, si nu este o chestie cu periodicitate definita.

Vibratia este destul de puternica pt ca este perceputa si de Ioana care deobicei este surdo-muta in privinta masinii :study: - adica daca merge este OK

[Andi TDI]

Si sigur nu este legata de pompa de servo ??

Stiu o alta Octavia la care rotirea volanului aduce o vibratie ciudata in sasiu. Cu capota ridicata nu se aude nimic in schimb se simte vibratia.(lichid servo are, suspectez tubulatura catre caseta care probabil are un colier slabit pe undeva)

Poti sa mai incerci amortizorul de la intinzatorul curelei de accesorii, am intalnit doua TDI-uri la care surubul era slabit si vibra.

[ender]

Se simte vibratie si la rotirea volanului la relanti dar este mult mai mica decit cea pe care am descris-o anterior.

Vibratia de la rotirea volanului cred ca este normala pt ca pompa servo consuma ceva energie si ECU compenseaza scaderea turatiei de relanti prin marirea cantitatii de motorina injectata

Am dreptate? Sau nu trebuie sa vibreze deloc la miscarea volanului la relanti?

Si apoi, de la ce poate fi vibratia descrisa in posturile anterioare? Este destul de neplacuta ... :study:

[stefison]

si eu am o problema de genul asta. la relanti tremura usor cateodata. usor si scurt. iar afara, daca stau cu urechea langa motor se aude ca un usor zanganit. ce credeti ca poate fi?

[stefison]

vad ca nu nea-m lamurit despre ce e vorba

deci, la relanti, pe loc, scos din viteze, din cand in cand in interior se simte ca o vibratie usoara, mai exact ca si cum motorul s-ar orpi o fractiune de secunda, iar afara se aude ca un zanganit

ceva idei?

[stefison]

eu am schimbat 0-ring-urile de la admisia intercooler si senzorul de temperatura motor si a disparut tremuriciul...