stock gsr running rich? need help

[lancerturbz]

Hey guys
I recently bought a 95 model gsr and it seems to be running rich.. The car is pretty much stock except for a 3" exhaust and a blow off valve, just wondering if it is a sensor or something any help would be good thanks

 

[VIN18M]

Blow off valve could be causing it. Try running a standard plumb back valve and see if anything changes. - Process of elimination, start with cheap fixes and go from there...

 

[lancerturbz]

I know the bov causes rough idle but didn't think it effects the fuel to air ratio. But I'll give it a go and see what happens cheers.

 

[BMGTZ]

why do do think it is running rich? have youb put a wideband up the exhaust and check the afr to confirm your thoughts?

 

[evo-gsr]

What ecu? If its a meek chipped computer...they all run rich.

 

[lancerturbz]

Black smoke and smell of unburnt fuel are my reasons of
Believing it's running rich and I wouldn't have a clue on what ecu it runs ..

 

[khubner1]

Because our cars use a maf running a vent to atmo bov will amuse it to run rich on back off.

Why? Because the ecu takes a signal from the maf and knows that much air is in the intake system once you dump that air out through the atmo bov the ecu doesn't know that air is gone and still pumps in enough fuel for it. This is why you get an initial rough idle.

If your idle is staying rough for a time after the bov has vented you have an issue with the bov causing it to stay open at idle. Increase the spring pressure and make sure its closed at idle if its not close at idle unmetered air is getting into the system and the ecu is dumping in more fuel to compensate.

 

[evo-gsr]

Black smoke and smell of unburnt fuel are my reasons of
Believing it's running rich and I wouldn't have a clue on what ecu it runs ..

Find out which ecu it has..it might help with solving your problem.

 

[4piknup]

Could be anything.
Dead plug even.

You can just block off the bov to try it

 

[VIN18M]

I was thinking that too jack, but blocking off the valve is the same as running it to atmosphere as the air isn't recirculating.

If the valve was leaking or not shutting correctly then blocking it would rectify the problem.

 

[BMGTZ]

Black smoke and smell of unburnt fuel are my reasons of
Believing it's running rich and I wouldn't have a clue on what ecu it runs ..

if it is as bad as the above suggests...I dont think it will be a bad chip. Unless the person that wrote the chip is a complete clown.

Check the airflow meter is properly connected......

has the fuel pump been upgraded?....possible failure of the fuel pressure reg.

injector maybe stuffed....try cleaning them, the guy doing the cleaning will pretty quickly find the dead one if that is the cause.

 

[lancerturbz]

if it is as bad as the above suggests...I dont think it will be a bad chip. Unless the person that wrote the chip is a complete clown.

Check the airflow meter is properly connected......

has the fuel pump been upgraded?....possible failure of the fuel pressure reg.

injector maybe stuffed....try cleaning them, the guy doing the cleaning will pretty quickly find the dead one if that is the cause.

 

[lancerturbz]

As far as I know the fuel pump is just standard , the computer is standard.. I blocked the bov off and it seems to run better can't see any smock at the moment but I'll keep checking for other things that may have been causing it thanks for the help guys