RB25 Expert Sought

[Penitent_Spark]

I was wondering if there was an RB25 expert or at least someone who is very knowledgeable about Skyline RB25DET engines. I have a few questions regarding mine and I would like to ask someone who is very competent with these engine a few questions in terms of idling, start up and normal running conditions.

I will throw in a six pack for your time.


Thank You

[Damo 69]

Tried skylines australia?

[KyeBidz]

PM Magic1

[Tom]

Post questions up, someone will stumble along them and might be able to answer.

[TJ]

PM SST

Plenty of rebuild experience

[Brockas]

PM Magic1
I lol'd.

[SimonR32]

PM Magic1

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[Penitent_Spark]

Thanks will try and PM Magic1 and SST.

Skyline Australia guys seem to give the same answer for everything and I have already tried that

[Penitent_Spark]

Also there is no one under the name SST, any one else I can try?

[TJ]

Ummm - just post the questions here?

[ossie_21]

The SST thing was just an hilarious joke, better off posting the questions you have for a start or speaking to a performance workshop...xspeed, in tune performance, all star garage etc

[Penitent_Spark]

I would just like to clarify if these are thing I should worry about and just send the car to the mechanic or if it's something that can wait till next service (in 3000ks, i service the car every 5000).

1.) The car is hunting around 100 - 130rpm at idle, I have found a vacuum leak - oil breather hose cracked, replaced with second hand one, replaced most of the vacuum hoses with new ones. It has now stopped stalling itself, but I am unable to get it to idle steady. There is no change when I disconnect the AAC valve and no change when I disconnect the TPS (slight change but then goes back to idling between 730 - 850 rpm)

2.)The Car is Hard to start when cold. Requires 2-3 pumps of the throttle before she cold idles.

3.) The injectors tick when cold for about 3 minutes, then they are quiet for the rest of the day. Is this something to worry about?

[magic1]

I would just like to clarify if these are thing I should worry about and just send the car to the mechanic or if it's something that can wait till next service (in 3000ks, i service the car every 5000).

1.) The car is hunting around 100 - 130rpm at idle, I have found a vacuum leak - oil breather hose cracked, replaced with second hand one, replaced most of the vacuum hoses with new ones. It has now stopped stalling itself, but I am unable to get it to idle steady. There is no change when I disconnect the AAC valve and no change when I disconnect the TPS (slight change but then goes back to idling between 730 - 850 rpm)

2.)The Car is Hard to start when cold. Requires 2-3 pumps of the throttle before she cold idles.

3.) The injectors tick when cold for about 3 minutes, then they are quiet for the rest of the day. Is this something to worry about?

this all could be fuel pump related.

[ossie_21]

^ that, could depend on what mods you have done too. The more info, the easier to find help

[Penitent_Spark]

The previous owner fitted a Walbro fuel pump, actually the 12/08/2008, surely they last a while, do they not? And how does that explain the ticking noise and would i not notice it while driving. Also why are warm starts no problem?

[Penitent_Spark]

Mods I am not too sure of all the mods but from what I can tell;

Titanium exhaust manifold with laser cut flanges

- Turbo back exhaust system with high flow cat convertor

- Custom 3" piping

- Front mount intercooler with custom piping

- Walboro fuel pump with regulator

- Large injectors on custom fuel rail (According to Seller)

- Chipped ECU (was running on Greddy E-manage now removed, though ECU still chipped)

- HKS SSQV blow off valve

[magic1]

Mods I am not too sure of all the mods but from what I can tell;

Titanium exhaust manifold with laser cut flanges

- Turbo back exhaust system with high flow cat convertor

- Custom 3" piping

- Front mount intercooler with custom piping

- Walboro fuel pump with regulator

- Large injectors on custom fuel rail (According to Seller)

- Chipped ECU (was running on Greddy E-manage now removed, though ECU still chipped)

- HKS SSQV blow off valve

AFM and HKS Super Squeaker will not be friends, it could be leaking at idle causing the hunting.

08 was walbro chani copy influx

larger injectors, take a picture and post.

purpo injectors std

[Penitent_Spark]

Great so I could potentially have a walbro china copy?


Is there a way to adjust the BOV spring, it does have one at the back, do I just turn it all the way in, or is there are more rigorous way, though I don't think it's leaking at idle

Will post a picture of the injectors soon, I wont be able to do it till the weekend probably though. I have some free time saturday.

[TJ]

No way you have titanium exhaust either.

[magic1]

i understand that you want to save money and not go to a mechanic but,

http://nigelburke.com/images/mechanic1.jpg

and

http://images.icanhascheezburger.com/completestore/2008/12/23/128745763802536789.jpg

where do you live?

[Brockas]

Not to be rude, but it's probably a 15+ year old car with mods?

If a 100rpm 'hunt' at idle has you this concerned, sell it now!! All those problems you listed are pretty normal and are probably nothing serious.

Large injectors with upgraded rails alone could account for every 'problem' you've listed.

[Penitent_Spark]

Brockas; You have a valid point. I have zero experience with these engine and just wanted to see if any of those were a cause for concern that's all.

Magic1; Just had the in for a major service about 5 weeks ago, the mechanic (Osborne Motors) was impressed with the overall condition of the engine for that age. These are symptoms that just appeared recentely and just wanted someones opinion if i should go back to the mechanic. I might just put in for another service when I come back from europe (going in three weeks).

Thank you all for the information.

[Penitent_Spark]

TJ- I also doubt I have a titanium exhaust manifold too this was just what it was advertised as, certainly doesn't look titatium.

[RRob]

Clearly you need to offer more than a "6 pack" and go to your workshop of choice.

[Penitent_Spark]

Maybe it was presumptuous and preemptive to assume that someone would take time out and have a look at my engine.

What I should have stated is the symptoms of what I think is wrong and asked for opinions to see if that is something to be concerned about. Unfortunately I have little experience with RB engines or with any engines that have been modifed, so I am not necessarily aware of how they should respond and what their characteristics are like.

All your opinions are greatly appreciated and it I will in future just consult my workshop if I have any dire concerns, which I don't at the moment.

Thanks to everyone who replied, you guys are awesome!

[magic1]

1. pic of injecting items?
2. your location?

[TheChad]

Standard cams and intake manifold?

I am impressed with your grasp of the English language, generally a rare trait among those arriving on forums with basic questions.

Are you really that worried, at the end of the day if it's not knocking, not leaning out and it still boosts fine then you just have a pretty normal RB with some light mods. Hunting idle could be perfectly normal for an aftermarket tune if you think it has one.

[caibs]

if you havent already; remove the aac valve and give it a real good clean with carby cleaner & refit with a new gasket. dont stress too much tho bud mine hunts like fuck and has the old ems stinger 'starts third time, every time' cold-start tune dialled in. she's alright but.

[Penitent_Spark]

TheCHad; Thank you. I believe the cams are standard. The Intake Manifold is definitely standard though it has an upgraded intercooler and a quiet a long intake path. I am not particularly worried, though I have booked in it at my local mechanic, for them to take a look, mainly because I enjoy this car a lot and would like to find problems before they develop into something unmanageable. There is a ticking sound, not unlike a solenoid or an electric arc at the back of the engine. I believe this has something to do with the idle hunt, I am not sure though, as I can't seem to find the source of it.

Caibs; I have removed the AAC and cleaned it. Also I have used gasket "goop" to remake the seal. You are right though, she's alright but.

Another update: I have found that the TPS voltage is was set at 1.2V at idle, so I have readjusted the voltage to 0.4V and reset the ECU. Though still no change, when the engine warms up, she starts hunting idle. Well it is more responsive now.

Will let you know what my mechanic finds.

[Orange_33]

thought TPS should be set at 1.2V at idle?