R32 Gts-t Dramas - Please Help!

[AzzurrA]

Hi All,

Well, more dramas with the car, after just waiting a month to get the bloody thing back from a simple 1/2 day turbo and intercooler swap!

Well, seeing as my turbo died (due to the heat recently i think ) i upgraded to an R33 unit, and also an R34 GTT intercooler...

Have barely driven the car since i got it back about a week ago, due to the hot weather.

I took it out and put it on the dyno today to check the AFR's, to make sure i wasn't running out of fuel/detonating with the hot weather we're having at the moment, and came across a bit of a shock when we found out that the car isn't leaving closed loop mode! (AFR's are at 14.8:1 from light throttle, all the way through to full throttle... i.e. it doesn't change like normal as it comes onto boost)

The workshop was busy, so they didn't have time to look at it/sus it out, but they suggested that there are only 3 things that control closed/open loop... these being:

AFM <-- I checked this, voltage readouts seem to be normal

TPS <-- Checked this as well, again, readouts seem to be normal

O2 Sensor <-- Now, im thinking this may have been damaged when the exhaust wheel of the turbo went kaput and ended up in my cat... The readouts are around 0.5 - 0.8v at extremely light throttle (i.e. just above idle) and then at much throttle at all, they drop rapidly, to around 0.02 - 0.05v.

Now, if anyone has any thoughts/ideas, they would be muchly appreciated...

Have done an ECU Diagnostic - Got Code 55 (All Clear)

Also did an O2 sensor test as outlined on the below site, and got no flashing LED's at all from the ECU....

http://www.overflow.250x.com/diagnostics.htm

Someone, please help!

[rory_kieran]

Hi Sir 32, I just bought a R32 GTS-t and it's a nice car however it is responsive but not as quick as imagined. I put a air flow system and new titanium spark plugs as well as a boost controller to 14psi but it still seems to run out of steam early on without no top end. I am putting a R33 turbo on like you have and was wondering if this makes a big difference and did you need to re-inforce anything. Can you please help me.

[Links]

I'm not sure what the issue could be - however if you get a consult cable + calumsult it could help you diagnose the issue as you can see what the sensor's are detecting..

if the O^2 sensor was broken - i'd be under the impression it would run very rich e.g. 10:1 AFR rather than 14:1 which is very very lean.. so I think you can rule that out possibly - but yeah - i'd recommend consult cable test..

good luck..

[AzzurrA]

I actually have a NissanDataScan unit, that Impakt off these forums makes... it gives a readout of all the sensor readings etc.... and like i said in the first post... sensors seem fine...

[Craved]

check the ECU with another standard unit.. if you have access to one.

my car wouldn't idle at all for a long time, everything seemed fine like yours. but when the power FC went in.. idled perfect.

just another idea.

[AzzurrA]

okay, anyone else got any more ideas? nobodys still been able to figure this out, and i'm about ready to just burn the piece of shit...

Elite 32 came around (thanks mate) and we swapped the O2 sensor for a good one, and everything seemed to be okay....

for a bit....

We put the new sensor in and took it for a drive, and on my handcontroller we could see that it was coming out of closed loop mode (cycling between rich and lean at low load) and then going constantly rich when i stood on it... all sounds fine!

i then took it for a drive by myself, and it was still cycling between lean and rich at light load, but then when i stood on it it would go constantly lean....

[BHDave]

You've forgotten all about your 15 year old fuel pump becoming tired. It's the prime suspect in 99% of running lean cases.

Get a new one. Genuine Walbros are under $200 delivered and are a drop in replacement. It's half an hours work.

Which workshop? I'm surprised it wasn't the first thing they suggested.

EDIT. Just re read your last post. O2 sensor has no control over high load mixtures as you are in open loop. Any improvement you got out of swapping the sensor was a bit of a fluke (quite possibly due to the car being fairly cool).

As you've said, the car is coming out of closed loop mode so you have eliminated all 3 possibilities you started with. Get a fuel pump.

Edited December 27, 2005 by BHDave

[AzzurrA]

i was thinking it might be the fuel pump... but if it was that, it would start out rich, and lean out as the revs rose, not stay a constant 14.8:1 from as soon as you touch the throttle, all the way through... wouldn't it?

[NewKleer]

have u done a fuel pressure check?

[AzzurrA]

thanks for that guys, i checked fuel pressure on wednesday afternoon, and found that at idle it was running around 2.5bar, and at normal driving it was running roughly 3bar... as soon as any throttle was given, it was dropping off to around 2.25 - 2.5bar.... looks like a new fuel pump and FPR is the way to go!

[T04GTR]

are you using the 33 or 32 oxysensor

[NewKleer]

do r32 have variable voltage fuel pumps? if so might want to just check and make sure that ur voltage isnt dropping off when ur fuel pressure drops to 2.5. glad u found that out though!

btw, id buy the fuel pump first, and see if that fixes it - FPR dont die as often as fuel pumps i dont think

[AzzurrA]

i'll need a FPR anyway, as i'm chasing around 200rwkw, and i'll either need an FPR, or an injector upgrade... FPR is cheaper option at the moment

[ronald_r32]

sorry to go a little off topic but there is a member with a link in there sig to a r32 buildup. ANd it that link is another one saying exactly how to install a r33 turbo on a r32. Just wondering if someone can tell me who the user is

[AzzurrA]

predator

http://www.project32.net

[ronald_r32]

thank you

[bretto]

hey ive had this problem and like u said the pressure drops as u stand on it. run a wire from the battery directly to your fuel pump. 32's are hopeless for that and you can kill a rand new fuel pump if you dont give it the right voltage. it happened to me before. might fix your dramas.