Fuel Cut Off bij de B200E/FT

Vanavond had ik, ondanks eerder berichten over het uitblijven ervan, toch weer een fuel cut off oftewel het inhouden bij snel accelereren. Ik kan de oorzaak nog niet achterhalen en zoek me wezenloos op diverse site's naar een oplossing hiervoor.
Vraag : wie heeft een B200E/FT en heeft een praktische oplossing hiertegen ?

Groet,
Roger Kuypers

Dit vond ik vanavond :
What is "fuel cut"?
When the ECU detects a condition that the factory didn't intend the
engine to experience, it will try to save the engine using something
commonly known as "fuel cut". All of the injectors are shut off as
well as all the spark plugs, effectively shutting down the engine. When the
condition has passed, the ECU will go back to running spark and fuel as normal.
You might experience this as a violent bucking sensation.
What conditions will cause fuel cut?
There are three conditions under which the DSM ECU will chop fuel.

1. Engine speed higher than 7500 RPM. This is overrev
   protection. If your engine rotates faster than the valve springs can pull the
   valves back up into the head, the pistons could smack into them, causing major
   damage. Note that simply chopping fuel will not stop the overrev condition if
   you misshift and the transmission rotates the engine past the revlimit. (The
   author did <a href=" www.tmo.com/%7Etoday/overrev/m3overrev.htm ">this
   to his friend's M3.)
2. Engine air flow greater than a certain amount. If the
   airflow into the becomes too great, the phenomenon by which the MAF counts the
   air entering the engine starts to break down, missing counts. The factory ECU
   sets a very conservative limit here. It doesn't need to be as conservative as
   it is to prevent missing counts. After we removed this limit, we were only able
   to hit the MAF counting breakdown problem on a first generation DSM with a 20G
   set to 19 psi on a 3" exhaust.
3. Engine under high vacuum for more than a couple seconds.
   This is not a matter of engine safety, but of smog control. Some of the worst
   smog can occur during engine deceleration. If you are coasting down a steep
   hill using the engine to help slow you, the ECU will turn off all fuel to the
   engine to both aid in engine braking and smog production.

What does fuel cut feel like?
Like you hit a brick wall, if it happens when you have the
throttle to the floor. Typically, the ECU thinks too much air is entering the
engine, the engine shuts completely off, the air amount decreases to under the
limit, and the engine goes back on again. This can be quite jerky.
Some days I get fuel cut, some days I don't, even running a consistent
boost pressure.
Fuel cut does not depend on boost pressure - it depends on
air flow. Remember the gas laws from high-school chemistry? If you keep the
pressure constant, you can pack more of a gas when it is cold into a given space
than when it is hot. So even if you keep your boost pressure the same, more air
will be flowing into your engine when it is cold at night or in winter than when
it is hot during the day or in summer. Thus, you might start experiencing fuel
cut at night or during winter that you don't experience at other times.
How can I prevent fuel cut from happening?
Of course, we recommend the Stage II ECU modification,
which removes the air flow limit imposed by the ECU. There are other methods
that use MAF modifications to "fool" the ECU into thinking less air is
entering the engine ("Dime Store Fuelcut Remover", MAF gutting).
There is a danger with these "fool-the-computer" mods, however. The
ECU might not provide as much fuel as the engine requires - possibly running
lean. With our modification, the ECU still knows exactly how much air is
entering the engine.
I am getting something that feels like fuel cut, but the car only has a
slight hesitation, not a dramatic on/off.
Here are three possible reasons for fuel-cut like hesitation. Keep in mind
that none of these involve the ECU directly.

1. Lack of spark. Under high boost conditions, if the spark
   is weak due to dirty plugs, it can be completely blown out. If the spark plug
   wires are old, the insulation might be breaking down, letting the spark arc to
   the engine instead of firing in the cylinder.
2. Lack of fuel. Fuel filter or fuel injectors could be
   clogged. The fuel pump might not have enough output to handle your fuel load.
   Sometimes, simply running an extra heavy gauge wire to the fuel pump can
   overcome voltage drops that occur when the pump is drawing a lot of current.
3. Modified MAF. If you have removed the honeycombs (they
   produce a laminar airflow) from a DSM MAF, you can disturb the phenomenon by
   which air flow is counted. If the MAF is missing air counts, the ECU will not
   put out enough fuel to properly match the air the engine is getting. This can
   cause a lean condition.

A possible fourth reason for this sort of fuel cut might occur if you have
our Stage II fuel cut removal and you are running a modified MAF on a 1st
generation DSM. The vortice field that the MAF uses to count the air might be
breaking down if there is air disturbance due to honeycomb removal. At this
point, you will want to step up to the large MAF used in the Stealth and the 2nd
generation DSM. Technomotive will has been running two daily driver cars with a
95 MAF with great results. Look for the 2G MAF upgrade soon.

Groet,

Roger Kuypers
Wolvega

Volvo 740 Turbo Intercooler
1989 Italie B200ET Black(line) Sedan 182.600
members.home.nl/rpakuypers

Ja een keer.
Toen ik een Impreza ging bijhouden, dat ging goed, tot een bepaald moment en toen was ie me kwijt. Tiens.. you can't have it all.
Ik heb wel eens gehoord dat je de injectoren uit een Porsche 928 kunt gebruiken voor meer flow, maar zou het niet je LMM kunnen zijn? want je zit zo te horen niet op max vermogen.
Maar die Golf GTI van gisteren die niet , had niet gekeken achterop natuurlijk, toen hij me wilde inhalen. RTFB!
het petje had zo'n gezicht:

ik had zo'n gezicht:




Groeten,
+++t blijft behelpen+++

Hallo Jeroen,
ik zit zeker nog niet op maximaal vermogen omdat ik de MBC op het gevoel heb afgestemd en ik hoop in Heerhugowaard met een turbodrukmeter het zaakje te kunnen finetunen. Ik denk dat mijn injectoren wel voldoende zijn, maar ik lees telkens dat de ECU in de weg zit.
Vorige week een keer met een warm motorblok flink doorgetrokken met een motor op de bumper, zo'n buikschuivertje en die had niet verwacht dat ie me 400 meter lang niet voorbij kon. Ik heb toen alle registers opengetrokken en dat ging echt wel hard, zonder fuel cut off overigens. Helaas is toen wel mijn verdeelkap gescheurd, maar gelukkig had ik de nieuwe al klaarliggen. De oude had ik twee dagen eerder nog schoongemaakt en geconstateerd dat de rotor en de koperen geleiders compleet zwart en zeer ruw waren.
Groet,

Roger KuypersWolvega

Volvo 740 Turbo Intercooler
1989 Italie B200ET Black(line) Sedan 182.600
members.home.nl/rpakuypers