Rb20det Stalling - Only When Hot

[Wheezy]

Hi crew,

My Silvertop RB20 is stalling when the car is warm.

Symptoms include:

Clutch in revs drop too low and the car stalls.

Eventually the car wont even idle.

I have new Splitfire coil packs and rebuilt injectors, and there is no missing in the revs under boost anywhere. (for those who know my car it gets alot of air and fuel in those cylinders )

My thoughts on this include, battery is not being charged by alternator, battery is dead, CAS f**ked or CAS wiring was f**ked up when I extended the wiring. Fuel pump is dyeing at low revs (12 month old Bosch 023) \ when heated up?

Remember, this only occurs when the engine is warmed up.

There also seems to be a voltage drop across the cars wiring, although this has occurred since I owned it.

Another thought is the 555cc RX7 injectors (rebuilt) and the Power FC not liking the de-celeration and turning the injectors off too long \ all together? I hear there are issues with this that cant be tuned out with the hardware on the FC.

Also, I do not have an IAC setup, only AAC (although I probably need the former more) This has not been a problem in the last 12 months before the last 2 weeks that I have noticed this.

Angry saw this occur 2 weeks ago, and today my missus took the car with me to work as hers is getting a new fuel pump.

At first Angry and I thought fouled plugs or lack of fuel, but the car did it at 1/2 tank this morning.

It could just be low fuel and the pump running out its supply, but crank it and it starts straight away and drives, drive on the highway without changing gear \ letting the revs drop and no problem.

It could also have a tune factor, since I fixed a leak in my intake manifold, but it is still weird to me.

Any thoughts to add to what I have described?

Cheers

-Jez

[STATUS]

i reckon now the manifold is fixed the idle mixtures are whack as..... drop in fixed in a flash, and you know its not gonna cost anything.

Edited August 28, 2009 by URAS

[Sami]

this issue has been raised before too

one thing to look for is FPR (Fuel Pressure regulator), i am not that much mechanically minded as to how it works but i was reading a thread on Nissansilvia and a guy had the same issue with his CA18det which is prettty much a smaller version of RB's he changed his FPR and problem was solved. (however i would do the usual things first like clean AFM, throttle body, idle controller spring etc)

if i find the thread i'll link it

edit: heres the link

http://www.nissansilvia.com/forums/index.p...howtopic=398535

Edited August 28, 2009 by Sami

[Wheezy]

NO AFM, Throttle body was just cleaned...No Idle control, AAC was cleaned, as mentioned NO IAC....

ummm, not stock FPR due to AM Fuel rail...

And Nismoid STFU about stock reg, its not by choice!

Trent, Ill call you monday

[_Ryan_]

Hey

I just went through this, Idled perfectly/strong on the cold start cycle, then hunted/died once warm. Disconnect your TPS once warm at idle and see if it idles. Mine did. Replaced TPS. I had a bad experience with a company(wrong part then three+ week wait for correct part then the plug is still wrong so we are still sorting that out) and I will PM you as they used to be a well regarded chain, now trading under another name in vic.

Best bet would be seeing is Streeter can source you one and send as they are ~150 new trade price here for the genuine part, or 200+ with a 2week wait through nissan.

Let me know how you go.

-Ryan

[Wheezy]

Cheers for the heads up mate, will give that a go tomorrow

EDIT: No bingo, same result

TPS voltage looks good from the FC Commander too...

[R31Nismoid]

NO AFM, Throttle body was just cleaned...No Idle control, AAC was cleaned, as mentioned NO IAC....

ummm, not stock FPR due to AM Fuel rail...

And Nismoid STFU about stock reg, its not by choice!

Trent, Ill call you monday

If its not the tune, then you might well have a voltage drop... in the 31 2-door?

I'm having voltage drop issues of my own when i use the windows causing it to dip a bit, nothing extra juice to the ECU wont fix though so that's something else to look into.

Why no IAC? How are you getting around it?

[Sami]

on the tps note... is the voltage meant to be 4.5??? just to make sure

[Wheezy]

If its not the tune, then you might well have a voltage drop... in the 31 2-door?

I'm having voltage drop issues of my own when i use the windows causing it to dip a bit, nothing extra juice to the ECU wont fix though so that's something else to look into.

Why no IAC? How are you getting around it?

Yup its in the HR, low revs, and you use something that needs some current, but it has been there for the 5 years I have owned the car. There is so much old wiring in these things its hard to track down. I previously got around it with a big ass battery but changed to a smaller one, now the battery is in a box in the boot so I could always buy a large commodore\falcon size battery.

No IAC because I just didn't really bother when putting the FF plenum on, it stood out like dogs balls on top of the plenum so I decided to tune without it. I may put it back in the system yet, but Trent seems to have worked around it.

[Wheezy]

on the tps note... is the voltage meant to be 4.5??? just to make sure

On WOT? Sounds about right.

[R31Nismoid]

Yup its in the HR, low revs, and you use something that needs some current, but it has been there for the 5 years I have owned the car. There is so much old wiring in these things its hard to track down. I previously got around it with a big ass battery but changed to a smaller one, now the battery is in a box in the boot so I could always buy a large commodore\falcon size battery.

No IAC because I just didn't really bother when putting the FF plenum on, it stood out like dogs balls on top of the plenum so I decided to tune without it. I may put it back in the system yet, but Trent seems to have worked around it.

You can give the ECU some extra power, i Andrew is rewiring my car tomorrow actually and we are gonna give the ECU a better feed rather than off the loom.

So should get rid of the drop, seems rather common actually more investigation i do into it

[Wheezy]

Yup sounds like the right thing to do

Previously bloke who owned the car had a Wolf V4 in it so the loom was hacked to shit, I ended up running a new loom to the fuse box when I put the Silvertop in a few years ago, and I couldnt get a ignition source so I ran one under the dash, but there is still issues elsewhere, could be on the alternator loom, not 100%, its the 3rd alternator in it too

[_Ryan_]

Yup sounds like the right thing to do

Previously bloke who owned the car had a Wolf V4 in it so the loom was hacked to shit, I ended up running a new loom to the fuse box when I put the Silvertop in a few years ago, and I couldnt get a ignition source so I ran one under the dash, but there is still issues elsewhere, could be on the alternator loom, not 100%, its the 3rd alternator in it too

Time for a rebuilt beefed up alt? best thing ever in old cars!!!

[Wheezy]

f**ker is supposed to be a brand newy when I purchased it 3 years ago. HR31's have some deamons that is for sure, but if it keeps giving me trouble I reckon some beefing up is in order

[R31Nismoid]

Which Alternator?

Im using a GTR one, always have actually even on the RB25

[Wheezy]

Hitachi for RB20DET Red Top. What is the current rating on the GTR alt?

[R31Nismoid]

No idea?

I think its 80 or 90 Amps, it was more than the RB25 one either way.