HELP! My r34 gtt is running super rich

[Jimmy1101]

Hey guys,

Iv had my 1998 nissan skyline for about 2 months now and iv been trying to figure out why its running so rich

Im getting 200ks A TANK!!!!. It blows black smoke and smells like fuel

Iv changed the o2 sensor, spark plugs, maf sensor 

When the car is off and  the engine is warm the car stuggles to turn back on... it turns on but then i have to tap the accelerator to keep it on

When im driving and coming to a stop i clutch in and slow down and the rpms drop below 1000 and sometimes even stalls 

When im speeding up and boost starts to build the car starts stuttering sounds like antilag tbh and i loose power

I dont know what it can be and would appreciate any help 

Thank you

[GTSBoy]

Boost/vacuum leak.

[blind_elk]

What about dirty injectors? How would a big dose of injector cleaner go?

[GTSBoy]

Nah, running filthy rich and not wanting to idle suggest a big fat hole somewhere. Dirty injectors usually lead to lean pops and only a moderate increase in fuel consumption.

[in71ce]

I had the same problem with my GTR and found it was the fuel pump control module in the boot was starting to die

[BK]

6 minutes ago, in71ce said:

I had the same problem with my GTR and found it was the fuel pump control module in the boot was starting to die

Um, how would the fuel pump control module make a car run rich ? All the GTR pump module does is put 6v, 9v or 12v to pump via dropping resistors within the unit, controlling how hard the pump runs. It could cause a lean condition, not a rich, as pump is not supplying enough fuel at load.

[in71ce]

7 minutes ago, BK said:

Um, how would the fuel pump control module make a car run rich ? All the GTR pump module does is put 6v, 9v or 12v to pump via dropping resistors within the unit, controlling how hard the pump runs. It could cause a lean condition, not a rich, as pump is not supplying enough fuel at load.

Im just stating what i have experienced

[BK]

And how did you find that out ? If module fails and pump runs flat out at 12v, injectors still deliver the same fuel as programmed. Like wiring a pump to run flat out all of the time, which a lot of people do, won't make any difference to injected fuel to make it run richer.

If the module fails so it makes the pump run not at 100% at say 9v, at WOT, then the car will lean out under load. That's like saying a failing pump can make a car run richer.

At no time can the fuel pump control module fail in any way to all of a sudden make the car run rich.

For OP I'm leaning towards a big vacuum leak too as @GTSBoy stated above.

[Jimmy1101]

21 hours ago, GTSBoy said:

Nah, running filthy rich and not wanting to idle suggest a big fat hole somewhere. Dirty injectors usually lead to lean pops and only a moderate increase in fuel consumption.

Will pull the injectors out to get them cleaned and i couldnt find any vacuum leaks anywhere 

Car idles fine just doesnt when the car is warm and iv clutched in while driving ....only last a couple seconds then will either stall or bounce back up and steady itself..

 

[GTSBoy]

Have you pressure tested the inlet from the turbo to the TB? Boost leak is not always going to show up as a vacuum leak.

And, for idle control, how sure are you that the IACV is working properly? Cleaned it lately? Your symptoms (rolling stall) are typical of a sticky IACV.

[Ben C34]

my vote is boost leak, and yo umust pressure test. thats a rule. you cant see them.

second vote is for coolant temp sensor.

both votes hold equal weight and if i am correct you owe me a favor. talk later.

[Ben C34]

also no way  never ever ever is it the injectors or fuel pump causing those symptoms.

[niZmO_Man]

When the standard ceramic turbine wheel shattered off the turbo in my R32 GTS-t, the car ran like shit and used a lot of fuel