Can Someone Please Help

[Starionturbo]

Guys, Ive read about 50 pages of stalling problems on this Forum and ive found no help at all.

My cars running very rough and idles like a drag car. When foot is down, car powers fine, doesnt lose any power drives normally. Car is a Series II R33.

I have, changed fuel filter, spark plugs, checked coils, cleaned out Air flow meter/plug but still it does this.

This happend out of the blue, my fuel tank was on empty at the time. I have a brand new Walbro fuel pump. I have a Remapped ECU.

The funny thing is, after I did this, for a while the car Idled fine, especially after I gave it a booting. Then out of the blue it would idle bad. Boot it again, and same story. Today while driving it, it was constantly idling bad. Like a drag car. Its not the same noise when a cylinder has dropped, but just like a lumpy cam and at times like rotational idle.

Im really stressed out over this. Does anyone have any suggestions. Could anyone possibly give me a hand?

Could the AFM or Crank angle sensor be the culprits? What about O2 sensor, how can I get this checked.

Regards

Kim

[KamikazeR33]

a new fuel reg should help fix ur problems kim

[Starionturbo]

Yeah? New fuel reg, do I get it from Nissan and have you had a similar problem?

Regards

Kim

[KamikazeR33]

id b goin for an adjustable one, u can buy them anywhere pretty much

the reason being its putting in more fuel than b4 when u had the stock fuel pump. over fueling a lil on idle

thats what im assuming the problem is. ive heard of a few others with the same problem

[paulr33]

if the crank angle sensor is borked i dont think the engine starts. if the afm is dirty it could be giving some screwy results, a quick check of a datalog using the standard consult connector/cable work reveal this. 02 sensor wont affect idle and is used for fuel economy feedback only.

i have a spare series 2 manual ecu and the stock data cable which may help you diag it more if you would like to borrow them/it.

let me know if you would me to help or you would like to borrow them. im in tullamarine / gladstone park. im home wednesday if that helps

[KamikazeR33]

but to make sure id take it to somewhere like ice performance, they should tell u wats wrong pretty quickly

[paulr33]

oh so since youve changed the pump its been idling crappy?

or has it been with the new pump ok for some time ?

[KamikazeR33]

paul im assuming hes just changed it as he sed "I have a brand new Walbro fuel pump"

thats y im thinkin needs a few reg. i remember gordo had the same problem on his r33

[Kaz200]

did you get it retuned after the fuel pump swap? sounds like not enough fuel on idle or afm is faulty.

[KamikazeR33]

nah kaz if there wasnt enough fuel on idle it would still ping. mine was overfuelling it it was doggy n would studder

broken afm would mean the car wouldnt move n only revs to 2500rpm (ive broken my afm b4)

[Kaz200]

doesn't move? Try having a faulty afm and having it stall on freeways at 100km/hr. A faulty AFM does not (only) mean the car doesn't move.

Also when my idle was hunting it was because it was running too lean

Anyway we have a consult plug here also if you want to come and hook it up.

Cheers,

Kaz

[KamikazeR33]

mine didnt. id try n reverse... stall, try first, stall....

[Starionturbo]

Hi guys

Ive had the Fuel pump for the last 8 months now, so absolutely nothing has changed on the car.

Paul that would be much appreciated, I will give the stock ECU a crack to see if its the problem, if not then ill get it on the Consult and have a look.

I have a feeling it is the Air flow meter.

[Kaz200]

kamikaze: there's definately more than one situation that can occur with a faulty afm so theres no need to argue with me.

[justin911]

try your own suggestion of cleaning the aac valve ??

[Julzy]

i doubt it would be the fuel reg... putting in a new fuel pump shouldn't change the fuel pressure in the rail at all as the FPR is set to a certain pressure. it would just mean that the fuel is recirculating through the system quicker than before if the pump is pumping harder.

does it seem to be running really rich? any extra smoke or anything on idle or when u boot it? definately sounds like a sensory problem. if i can get some time at all i'll let ya swap over my afm to see if thats the problem. but i'll be flat out the next few days though.

[NateR31]

this happnd to me when i changed my plugs, it eventualy just went away.

[Starionturbo]

It was happening before I changed the plugs so I dont really know, its a mysterious problem.

Anyone else whos had similar problems please let me know.

Regards

Kim

[Starionturbo]

Julzy thanks for the offer might have to take u up on that, where are you located?

Question though, are Series I and II air flow meters the same? I know S IIs ones have a pink label and S I has a green label. Any differences?

[ylwgtr2]

for gods sakes just bridge out the ecu and do an OBD test....i see so many threads like this its your afm its you reg its your fuel pump....its really not that hard and the car has the facillity to do it all by itself and best of all......its free