THIS LOW RPM ENGINE STALLING SAGA POSSIBLY SORTED

[RBVS]

I Have a rb25det fitted in a vs commodore. I also have the same prob. happens on a worm start , ethier starts then stalls a few times, or drive around the corner and stall at the lights or stop sign.

just thought there maybe be more to it.

[AutoTrust]

RBVS, nice choice of engine! Book it in at the local holden dealer for a service .....just to see the look on their faces!! .......... seriously though, try raising your idle speed using the idle air adjustment it worked for me.

[RBVS]

yea i will try that. the head is off at the moment, cleaning after a blown turbo.

so ill give it a go when every things back together.

:headspin:

[Madtrang]

My 32 stalls when the A/C is on @ idle. The compressor turns on and off, I also notice when my car idl'es with the a/c off the idle revs do fluctuate a little.

my r32 is completely stock with excetion from the exhaust and turbo timmer.

What does th IAC valve look like on a 32?

can u pull it apart, I pulled the AAC valve and the bit it connected 2, cleaned that allo out, but still has the same problem.

planning to look at the afm thus afternoon. Give that a clean ouot, any sugestion on cleaning the afm?

[Madtrang]

My 32 stalls when the A/C is on @ idle. The compressors turns on and off two, I also notice when my car idl'es with the a/c off the idle revs do fluctuate a little.

What does th IAC valve look like on a 32?

can u pull it apart, I pulled the AAC valve and the bit it connected 2, cleaned that allo out, but still has the same problem.  

planning to look at the afm thus afternoon. Give that a clean ouot, any sugestion on cleaning the afm?

[stimps]

The stalling at trailing throttle with warm motor on the rb25det is a common problem with the 2.5 litre square bore 6. There are many many reasons, and I have been plauged with it since day one.

I have a rb25 with a Haltech E6K and used to do it always unless i keep things fine tuned.

THere are several things you can try.

Obviously the earthing of the fuel pump will work, as it will keep the fuel pressure constant, and keep your fuel mixtures good at idle.

If you have aftermarket managment, try leaning off the mixtures around 10% at the 0 - 500rpm map. Leaning off helps keep the revs up. Leaning off too much will cause it to hunt tho, so it takes some fiddling to get right. Remember that you must do this tuning with the engine warm. NOT COLD. or you will have to reset the cold start map again.

ALso try opening the base idle screw a tad, raise the idle to 900 - 1100 rpm. All rb motors seem to like a high idle, guess this is why they are called a RB "racing block"

Some people even raise the advance at the 0 - 500rpm map to help keep the power and revs up in this area of the map.

typically, engines have a slightly rich mixture at idle to help keep the idle stable, and keep it from hunting.

another thing you can try is turn off decel cutoff. This turns off the fuel on deceleration, and sometimes doenst kick back in untill its too late, and the engine has stalled.

its all just a fine balance really between fuel, revs, and air, and you have to find that balance.

Also, if you have a BOV that leaks at idle, you can get this problem. Vacumn causing extra air to be sucked into the manifold throught the BOV can lean out the mixture too much and cause instability and stalling.

I used to raise the base idle screw just a tad (so it would idle at 800rpm) adjust the mixture so its ever so SLIGHTLY richer than sticiometric, raise the spark advance a little more than even at the 0 - 500 mark, and leave the decel cutoff feature disabled and it would have no problems.

Of course, you loose out on economy just a little bit, but there are some small sacrifices you simply have to make sometimes in order to get a very well behaved engine.

These engines even in stock form have a very high Volumetric effeciency, so when they are idling around 600-700 rpm, they are practicly idling in a vacumn. Show me anyone that has a modified rb25 that idles pefectly like a brand new stock one, and ill show you someone who can fine tune.

[mtopxsecret6]

So is someone going to help out all those who are asking which wire is the ground wire for the fuel pump, or is everyone going to be ignorant and just turn a blind eye to those who havent an idea such as myself? I have had a look, and found a ground wire from the case of the fuel pump top, and i dont see how moving that to a new better earth would work, as it is securly attached to the top case from the factory..?

[AutoTrust]

So is someone going to help out all those who are asking which wire is the ground wire for the fuel pump, or is everyone going to be ignorant and just turn a blind eye to those who havent an idea such as myself? I have had a look, and found a ground wire from the case of the fuel pump top, and i dont see how moving that to a new better earth would work, as it is securly attached to the top case from the factory..?

I considered this modification, and decided against it, therefore I can't tell you how to do it.

I would recommend adjusting the idle air by-pass before modifying the fuel wiring.

And take it easy man

This thread is pretty old.

[mtopxsecret6]

i'll give that a shot i guess... thanks dude, not annoyed or anything.. just trying to get important info outta people.

[r32impul]

I also have the engine stalling problem b4, but now I putting a new 600hp intank surge fuel pump and a 1000hp external fuel with surge pump, it seems the problem gone. The mircotech also seems works much better than e-manage too

[RedDrifter]

Damn I'll never look into my fuel tank with a torch ever again. When I change my fuel pump I did exactly that. I had about a 1/4 of a tank of fuel.

Thank god I wasn't toasted.

[wados]

i got the idle speed controller changed today to rev more and now i dont stall i know the problem is not fixed but it wont stall anymore witch is what i need right now so i thought maybe some of you should give it a go only took about 5 minutes

[stimps]

the flat screwdriver type screw above the idle solenoid is the manual idle screw. Turn it a few turns out will raise your idle a bit, and help prevent stalling.

[williamc]

Hi,

Yeah the HKS EIDS (electronic idle stabiliser) is used to help this problem. It electronically adjusts the rpm curve when the throttle is released. Ive got one inbuilt on the HKS boost controller that im about to install.

ps. check out the for sale section, as I have a stand alone unit for sale.

Will

[the phantom]

I've also experimented with an HKS EIDS. It can be helpful in some situations, but isn't good enough in my opinion to adequately solve other underlying issues responsible for idle problems.

It intercepts and modifies the AFM signal to the ECU. It replaces the AFM signal when it drops suddenly, such as on throttle closure, and substitutes it with a constant voltage which is adjusted for magnitude and duration, as required to eliminate the stalling. It's one dimensional nature is the reason for its inadequacy in my opinion. Although I am particular about idle quality, others may find it acceptable.

[HappyPuppy]

Probably a red herring, but my old '85 Corona use to do the same thing. Idle badly once the engine was warm, and cut out when you lift off the accelerator when changing down from 2nd to 1st. It was an intermittent fault too...you'd be driving around car with the car perfectly happy and then you stop at the lights and the damn thing just wouldn't hold it's revs.

Took it to the mechanic once, but they had no idea. I always thought it might've been the fault of the crap battery and the alternator slowly dying....but then again I'm not a mechanic...

[mAtTYb-R33]

i had that ita a screw or something they need to adjust or lube up and its fixed also idle adjusted up a bit (mine was on 575rpm)

[Ska]

I had the same problem with my R33 S1, turned out to be a clogged fuel filter + the previous owner took it to a mechanic who obviously did not know what he was doing and had too small a hose fitted to the MAP sensor. Now runs sweet as!

[the phantom]

Hey Ska,

The R33 has NO map sensor. The small hose comming from the plenum and plugging into a sensor is purely for the boost gauge on the dash. No input from it goes to the ECU. Your relatively lucky finding such a simple solution to your problem

[Ska]

Oh sorry, I am very mechanically challenged, just repeating what the mechanic said yeah glad it was a simple fix though