Hi

when im driving my 2000 impreza hen i come to a stop or to a juction
the revs drop and some times cuts out...

i have just had it re-mapped and was fine before it was re-mapped
i have cleand the idle valve and checked all the pipes

the only thing is that i ahve a blitz dump valve fitted could this be the problem?

thanks

 

Check all tight could be an air leak.

 

What model year is your car and who mapped it? If you haven't done so already it'd be worth having a word with the mapper and asking if there were any issues with the mass airflow sensor output during the session.

Was this fitted while the car was being mapped, or have you added it on since? If the latter it'd certainly be worth refitting the standard one to see if it makes any difference.

How is the idle stability generally, btw? Once it settles down does it stick at roughly the same engine speed or does it hunt up and down?

 

it was mapped by clive atthowes and its mapped with a
its a 2000 uk turbo

apexi power fc with controller
hybird gt 2 fmic
blitz dump vlave
hrc fuel pump
hks air filter
all these parts were fitted when he mapped the car
he told me he had no problems while mapping it,it had a new air flow meter a few months ago
it idles fine its only when you stop....

 

CTS? TPS?

 

If the CTS is faulty, you'll see a suspect reading on the commander.

TPS should read approx 0.5V on a closed throttle and 4.3V when fully opened - Theses can be checked on the Hand Commander under the ETC-> Sensor/Switches screen.

Possibly a MAF or ISCV fault.

What Airflow reading do you get with the Ignition on, engine not running?
What airflow at warm idle

Also worth asking whoever mapped the car, what the Fuel Cut (F/C1) and Target Idle Speeds are set to.

 

Oops, I overlooked that the OP had a PFC/Commander. As above ^^^

 

I favour FC23

Tony

 

No fault codes on a PowerFC - just need to look at sensor voltages, and 'out of expected range' faults

 

dv may be sticking

 

the mapped has looked at the car and checked all the sensors and said they all look fine
he said that the dump valve could be the problem so im gonna swap over and see what happens

 

Did you get to the bottem of this yet BBB3 ?

 

yes i did mate,got it done a while back it was the dump valve sticking as it was a blitz
have a forge fitted now which is better and has been mapped again to be on the safe side so its a daily driver @ 340 bhp which is plenty around here....