A couple of questions after a local ASN meet yesterday ...

S3 Paul

Well-Known Member
Joined
Oct 27, 2006
Messages
2,851
Reaction score
110
Points
63
I took my son to the local meet yesterday ( nice to meet a few of you)
after talking to Dan I was left with a couple of questions in my head...
1. When doing the N249 bypass I was told it needed to be left electrically connected but not piped up?
my car is face lift and dans is not if this makes a difference. He didn't have it fitted and the plug was just sat there?
Do I need the valve in place? I thought I did? He reports no loss in performance,
2. Regarding catch can location...
Mine is located on the Side of the battery box, his slightly higher, but he was told by another member on here that the can needs to be as high as the rocker cover breather outlet?
is this true? Why?
the pipe back into the tip ( before fitting a catch can ) is lower that the rocker cover .
i have no problems that I know of with my set up...
 
1. It will throw codes and lights if not connected. Leave it connected imo.

2. Dunno what all those ideas are about. The breathers just need somewhere to go, doesnt really matter imo
 
These are the same replays I gave on the day... But I'm not always right...
I'm sure tuffty said leave it connected, so I did,
breather wise... I said venting directly to air would be ideal but messy. So why does it matter where the can goes?
 
Is Dans me7 and yours ME7.5? if ME7 is half as dumb as me3.8 it'll never throw a light for anything where me7.5 throws a fit if you wear the wrong colour socks....

I was always led to believe that removing an N249 or N112 without leaving the valve plugged in would stop fuelling adaptations from taking place.

Not sure if this is the case with a resistor in place or not, but I'd like to find out for a mate also.
 
mine doesnt fill fast either - and as with prawn, its on bolted to the battery cover.

havent drained mine in couple of weeks, and a check over the weekend shows its only about 1cm full
 
Just bought the same catch can as prawn :) hope it works!
 
Just to add, i have left the n112 valve connected as when welly disconnected this, it messed fuelling up big time, the n249 on the other hand is totally removed and fine.

Yes Nick mine is the APY s3 so has the ME7.

Also pauls catch can is lower than mine but mine fills up on a regular basis, and its not a cheap one, its the expensive one we all got in the group buy.
 
Surely that so long as the correct value resistor is selected, it will be fine?

The solenoid afterall just presents a resistance to the ECU...
 
Rather than mess about with resistors i will leave well alone.
My catch can has been on a good couple of months now and i havent had to empty it yet. I will check at dinner time but ...it was clear after a month.
 
If you have the valve why buy a resistor? extend the wires to the valve and hide it out the way if going for a tidy bay... I put mine in the plastic housing where most people fit catch cans but have also secured N249's under the inlet manifold as there is a handy bracket on the oil filter housing

Resistive loads present differently to inductive loads is my understanding... current draw can be different... I would rather just use the valve than a resistor having the choice...

<tuffty/>
 
  • Like
Reactions: Westy
Surely that so long as the correct value resistor is selected, it will be fine?

The solenoid afterall just presents a resistance to the ECU...

inductive load
resistive load

do the n112/n249 solenoids ever feel "warm" to touch? = No
do the n112/n249 resistors ever feel "warm" to touch? = Yes

now ask yourself why?
 
Glad the topic has gone this way.

My mates Ibiza has resistors in place of the N112 and N249 valves, and also has all sorts of crazy manner of fuelling issues (fuel pump most likely)

I suggested he refit the valves electrically but leave the plumbing as is.
 
inductive load
resistive load

do the n112/n249 solenoids ever feel "warm" to touch? = No
do the n112/n249 resistors ever feel "warm" to touch? = Yes

now ask yourself why?

The oft touted resistor value is 330ohm, which will sink about 36mA, and dissipate about half a watt at 12v.

One would imagine that even if the stock resistance of the coil was 330ohm, the much larger N112/N249 valve would take a LOT longer to heat up, due to its much larger thermal mass, and would also dissipate heat more readily, given its much larger surface area. Surface temperature alone therefore is no indication that its somehow drawing more current.

Theres also not much in the way of inductance in a steady state DC load, inductors essentially appear as shorts when supplied with DC...
 
you presume they are steady state and not pwm switched to activate

Reality is many "resistored" sensors I see come thru here are hot as hell... some melted into adjacent wires they got so hot..
Never see the original solenoids get warm..

and.... in ibiza's, I dont believe its a coincidence I see many with lambda b1s1 malfunction in circuit errors on cars with resistored out solenoids. When/If I get a mo one day I will just stick the DVM on amps and do such a test to confirm actual current draw the ecu is having to switch out. (switches to ground to turn things on generally)
 
Glad the topic has gone this way.

My mates Ibiza has resistors in place of the N112 and N249 valves, and also has all sorts of crazy manner of fuelling issues (fuel pump most likely)

I suggested he refit the valves electrically but leave the plumbing as is.

I think his issue is pump.. ibiza pumps suk
unless he has b1s1 malfunction in circuit error, in which case it may fuel adjust +25% randomly.. Not found the cause or solution for this either.. and tried many many things..