samcowrx

Basically my sti 2 is fine, although bit down on boost, dont know if that could be related?, but when the fans kick in or i put on the heated rear screen the idle goes up too 2.2/2.3k revs until the fans go off or i turn the screen off!, running a simtek, 20g and all supporting mods. (did melt the loom on the headers, but that is now properly repaired).
All help appreciated!
thanks

samcowrx

help please?

samcowrx

bttt

jonboy0373

i know on one of my cars as you req extra load the ecu increases the rpm and then the alternator provides more amperage to cope, as for scoobs doing the same not sure, but place the engine at idle then turn steering the revs may increase

samcowrx

Any other thoughts please?

apalmer

iTrader: (8)

Battery adder table under fuelling?

samcowrx

Hi mate, would you explain what you mean please?

Jolly Green Monster

iTrader: (4)

assuming it was all fine before the wiring melting incident then it cannot be related to the map as suggested.

Perhaps you have damaged more of the loom.. ie. melted the fan wiring to the idle motor wiring.. so when the fan kicks in the idle motor is fully openned and the idle increases..

or you have damaged the ecu when the wiring melted.

Simon

samcowrx

Thanks Simon, is it possible at all in any way that the map could have been altered from the wires shorting?,if the ecu is damaged what might the options be?, i am pretty sure that no cables are shorting now, if they are i dont think its in the engine bay so i am cluless if thats the problem. Maybe a sensor naffed?

I am at the point now where i am considering buying another Impreza and breaking this thing.

Jolly Green Monster

iTrader: (4)

if you remove the ecu board from the case.. any damage should be obvious..

my understanding is that it would have erased / damaged the device the map is stored on.. ie. all of it.. not just one bit

P1 Daveyboy

Try a "drop test" on the battery. What that means is a tester is connected to the battery which puts it under load condition. If the power level drops straight away it means the battery is on its way out. If the power level remains constant the battery is ok. Not sure if Kwik fit do this test but maybe a local garage will have the kit required.
The reason for battery test is you say when a "load" is switched on the revs go up. Sounds like the revs are compensating for the extra load being pulled on the battery. Had this in the past but not on a scoob. Good luck anyway

Jolly Green Monster

iTrader: (4)

simtek doesn't increase idle speed with load tohugh.. it only as apalmer says alters the fuelling with battery voltage, but if there was a fault with that table then it would have done it before the electrical wiring meltdown.

it is possible if the battery fuel adder table was too lean for the idle to increase a small amount and then clip into an ignition cell with higher ignition and cause the idle to increase but unlikely to increase to 2000+rpm without alteration to either the idle motor position or something that alters the idle motor position like coolant temp as seen at the ecu..

imho there is still a wiring fault or some damage to the ecu.

I would be happy to take a look as it would be easy from monitoring the ecu sw and examining the ecu circuitry to establish the problem or at least narrow it down but suggest OP sees his mapper which isn't me

Simon

samcowrx

Ok Simon thanks, that makes sense.
Daveyboy, i like your idea and will give it a go!, if thats what it is i will owe you thanks!

samcowrx

Thinking about a battery not up to scratch, the car starts very well, and the only time the revs rise is when the cooling fans are on, or when i turn on the rear screen, it does not effect the revs when a have all the lights on and the heater fan full on etc, so that is pointing more towards wiring than the battery?

Jolly Green Monster

iTrader: (4)

imho yes..

from memory within the simtek circuitry the rev needle and fans are on the same circuit so if you had damaged the ecu I would expect the rev needle to cut out or misbehave when the fans cut in or them both not work..

I assume the engine does increase in revs and not just the needle

Simon

samcowrx

pm sent Simon