over fueling Legnum

[sideburns]

Hey need some help I have a 1998 Legnum that's over fueling at idle
I've put a fuel pressure regulator on it injectors spark plugs maf sensor and ecu and is still doing it
Not sure what to try next what does everyone think?
Thanks

 

[trotty]

Have u tried the O2 sensor in the exhaust? Have u got any vacuum leaks?

 

[VOLK]

Vac leaks/water temp sensor has failed/dead O2 sensor.

 

[sideburns]

It's not bringing up any engine fault codes no vac leaks and I haven't tried an o 2 sensor but that would bring up a code

 

[vr4cobra]

Not necessarily bring up a code, just make u run rich like having an exhaust leak before the sensor too

 

[fieldy107]

When you say over fueling do you mean revs keep rising and falling? If that is the case it is most likely a vac leak. I had this happen when I had a split injector seal, but it really could be a lot of different things causing a vac leak.

 

[sideburns]

Na it doesn't have a vacuum leak ice changed all the injector seals and everything and it doesn't have an exhaust leak either...

 

[VOLK]

So you've done a boost leak test then? There's plenty of spots they leak, not just the things you've changed.

 

[king_panther]

Do all the things suggested above then get back to us.

 

[naughtika]

coincidentally, James is having the same issue..

 

[sideburns]

Yeah it's not just on boost can't hear any leaks bit will check everything tomorrow also checking return line isn't blocked or anything Thanks

 

[Scubasteve]

Any progress on this im having a similar issue ?

 

[sideburns]

Not really scoped the injectors and it's holding them open for too long,crank angle sensor is fine so I'm going to check the maf and make sure it's to specs

 

[TME_Steve]

Just so you all know, the O2 sensor was disabled in the ecu as well, made no difference, tried maf, plugs, coilpacks, leads, bypassing the fuel reg solenoid, no boost leaks, on boost it actually runs like it should, off boost, rich as feck, no error codes. But Dave has measured 0.15ms pulsewidth on the scope at idle, so this is 75% duty cycle at 600rpm if my maths is right. Tried a second ecu too and EVO scan and another scan tool both say it is running at 0.02ms. Seriously wtf?

 

[sideburns]

Well said Steve and it is a weird issue and wiring to injectors is fine too so is time to start checking wiring to the other sensors and disconnecting until I find something

 

[AKKO]

bump

 

[jungle]

left field, still got standard injectors Steve?
And when you say over fuelling, what is it doing to determine that?
Change the O2 sensor. If it's right everywhere else, maybe it has an issue at the low end of the voltage scale?

 

[Scubasteve]

If it helps, it turned out that 1 of my injectors were faulty. I worked out which 1 whilst checking my spark plugs. Replaced it and no issues since..

 

[jungle]

There you go, my gut was something injector related
ALways nice to find a hard fault!

 

[TME_Steve]

Just so everyone else knows. the op problem was a tps giving some weird back feed into the ecu and causing it to do weird crap