Jump to content
SAU Community

Rocker Cover Gasket Changed, Now Stalling Occasionally In Neutral?

mosquitocoils

By mosquitocoils,
in General Maintenance

 Share

Recommended Posts

mosquitocoils Veteran

mosquitocoils

Posted
Posted

Hi guys, I've had my rocker cover gasket replaced by a mechanic who did a bit of a shit job. Several hoses were not reconnected when I picked the car up, and clamps left off too.

So after a few trips to autobarn etc to fix my car up myself (cause I don't trust that mechanic, and would rather save on labour costs) I have clamped most everything down nicely again and replaced some broken hoses / vacuum lines. Replaced my boost controller / gauge lines which is something I've been meaning to do since I bought my car. Not too comfortable doing more difficult work than this.

So anyway, my problem now is 2-fold. I can accelerate and get up to 4th gear fine, then when I go into neutral and coast (like for a red light) the revs drop quite low (350 - 500 rpm) and it stalls occasionally.

The other issue is when I accelerate with low boost it's boosting fine, but once it hits about 5 psi I hear a high pitched squeal coming from my Autometer boost gauge in my dash.

I've turned my boost controller down to minimum for the time being to make sure I don't overboost or anything as I'm not sure if the gauge is not reading correctly.

I've had someone suggest getting a new boost gauge.. but I don't agree as it's been reading fine until the day my rocker cover gasket was replaced... which makes me think it's something to do with a vacuum line or something.... can this cause this squeal all the way through to my dash?

I'm planning on doing the AAC valve clean and idle reset if I get the chance in the next couple of days, unless anyone can offer some advice from a similar situation? (removing lots from the top of the engine etc)

Thanks for any info guys.

Ravi

br3ndan Mentor

br3ndan

Posted
Posted

^+1

probably a vaccum hose some where that hasnt been connected properly and is leaking

Hard to find mechanics who will do a good job now a days... Im sure you will find the problem soon.

  • 3 weeks later...
mosquitocoils Veteran

mosquitocoils

Posted
  • Author
Posted

So I had a loose intercooler piping clamp... fixed now.

Also my boost gauge line coming off the back of the intake was leaking badly... which was explaining the squealing noise. It's not heaps better now, but it seems more air tight and not leaking or making the noise.

Just some ideas for people to look at if they find a similar problem.

Thanks for your help guys.

  • 3 weeks later...
mosquitocoils Veteran

mosquitocoils

Posted
  • Author
Posted

Just to add a little correction, it turns out my gauge was fine and the connection on it was not the issue at all.

I've since found a 2nd leak in my intercooler piping, due to the clamps not being in the right spot to seal the silicon tubing completely. Anyone having similar issues should check every coupling, by loosening the clamp, lifting it off it's position on the silicon and re-setting it in place.

And thanks Craved. I always find it useful when others post the resolution so it makes sense to do it for others too ;)

NZM.031 Grand Master

NZM.031

Posted
Posted

i had a similar prob when i used cheap ebay coloured vacuum hose... when it got hot, it became flimsy and would suck itself in make a squealing sound like a balloon does.. i also had one split slightly, again due to the heat.. would squeal when boosting, suck in when idling.

sounds like you need to get a hose kit and go over everything!

smok74 Community Regular

smok74

Posted
Posted

What to do .... what to do......

Get a few of meters of brand new vac line...AND NOT SOME CHEAP SHIT EITHER, The best Ive found is 3mm ID stuff made by SARD, as it's only 3mm ID, it will be very tight fitting on all the nipples (GOTTA BECAREFUL ESPECIALLY IF YOU USE TURBOSMART BOV OR WASTEGATES as they tend to have really small/thin nipples), once you have replaced them all, tie them off at each nipple with a cable tie or two. As with all the pretty colourful 'silicone' stuff that's around, let me tell you guys, the blue or red stuff that the hoses are made off is NOT silicon ! That's in fact synthatic rubber, when people refer to silicon hoses, theyre talking about the silicon fibres that's used to reinforce the make up of the hose (kinda like fibre glass and polyester resin OR carbon fibre and epoxy resin etc)...... When you get down to the vacumn line sizes, there is in fact NO SILICON fibres used in the make up, so you might as well be buying normal rubber vac lines !!

With the intercooler joiners, what I found is, slip the joiners on and when you fit & tighten down the clamps, have them sit on a slight angle, kinda like wedged across. I find it to have a better seal and less room for it to move, slipping and/or popping off under hight boost.

.... all common sense really......

Good luck.

mosquitocoils Veteran

mosquitocoils

Posted
  • Author
Posted

Hi again, thanks for all of your input. Thought it was time for an update... I think I found the problem!!

It was my stock BOV. After the dickhead of a mechanic gave me my car back half completed, he didn't tighten the bolts that hold the BOV on. It was 'ok' but not GREAT. Also the gasket wasn't proving very airtight, so I took it off and reset it in place basically just by turning it 180 degrees.

Through this process I've replaced much of the easily accessible vacuum lines and a few of the other things like breather pipes/AAC valve feeder because they were old and fraying/splitting. Definately holding it's idle very well now, and boosting properly without squealing.

Again, thanks for all your help. I just hope that if someone has a similar experience in future they might get some info from this thread.

smok74 Community Regular

smok74

Posted
Posted
Hi again, thanks for all of your input. Thought it was time for an update... I think I found the problem!!

It was my stock BOV. After the dickhead of a mechanic gave me my car back half completed, he didn't tighten the bolts that hold the BOV on. It was 'ok' but not GREAT. Also the gasket wasn't proving very airtight, so I took it off and reset it in place basically just by turning it 180 degrees.

Through this process I've replaced much of the easily accessible vacuum lines and a few of the other things like breather pipes/AAC valve feeder because they were old and fraying/splitting. Definately holding it's idle very well now, and boosting properly without squealing.

Again, thanks for all your help. I just hope that if someone has a similar experience in future they might get some info from this thread.

Errr that doesnt make sense, the factory BOV is supposed to be plumbed back into the inlet by venting into a pipe with the BOV facing the passenger side of the car.... Unless your BOV isnt plumbed back....then the engine would be farting and puffing in between gears as the ECU over fuels it.

NZM.031 Grand Master

NZM.031

Posted
Posted

not nececelery... the bov would have been being sucked down at idle by the vacuum... and then when boosting, yeh it would be overfueling and popping a bit more than normal but if it was done up, just not tight, it would have been a small leak and hardly noticable except for the noise.

mosquitocoils Veteran

mosquitocoils

Posted
  • Author
Posted
not nececelery... the bov would have been being sucked down at idle by the vacuum... and then when boosting, yeh it would be overfueling and popping a bit more than normal but if it was done up, just not tight, it would have been a small leak and hardly noticable except for the noise.

Yeah that's what I'm thinking was happening too. Took it for a good long drive again tonight and it's not squealing so I'm positive this has done it!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Wazmond
      Stock rb25det neo questions

      By Wazmond · Posted

      Hows your intake piping? Are you still running stock? Having in the stock AFM position would mean, if the BOV was shut/venting out, it'd create the almost stalling kind of effect right // "the rich pulse behaviour" due to MAF thinking air is flowing ? But this would be better than having the bov in the stock position + MAF on/just before cross over piping right?
    • GTSBoy
      Stock rb25det neo questions

      By GTSBoy · Posted

      Essentially, yes. Although I wouldn't put the AFM on the crossover pipe. I'd want to put it into what amounts to the correct size tube, which is more easily done in the intercooler pipework. I bought a mount tube for card stile AFM that replaces the stock AFM - although being a cheap AliExpress knockoff, it had not flange and I had to make and weld my own. But it is the same length and diameter as the stock RB AFM, goes on my airbox, etc etc. I don't have a sick enough rig to warrant anything different, and the swap will take 5 minutes (when I finally get around to it and the injectors & the dyno tune).
    • Wazmond
      Stock rb25det neo questions

      By Wazmond · Posted

      So to summarise, the best thing to do is to move recirc to between turbo and IC, and maf on the crossover pipe. Meaning I'd need a recirc flange, drill a hole in the piping on turbo outlet area. And drill hole on crossover to fit/weld maf sensor? Either that or put the MAF on the turbo inlet right?  Is an aftermarket recirc/blowoff valve recommended? Do currently have family in Japan so could probably bring something back with maybe a cheeky lil SuperAutobacs run?
    • tsuokun
      Lets play a game - What is causing my oil consumption?

      By tsuokun · Posted

      Yep, so far most have said that it looks like corrosion on the wall from piston not moving. Which then has probably damaged the oil rings and caused those vertical marks. The longest the engine was still after the rebuild, was the winter of 2018 - 2019, plus the boat trip to Japan. When I shipped the car, it had normal gas in the tank but before that winter pause, it had E85 in tank.  In any case, even if either one of those was the cause, it happened close to 6 years ago and the car has been driven something like 30 000kms after the fact. Again, apart from the plugs and the dip stick, there is nothing in the way the car runs that would indicate what has been going on in the engine. I am going to consult a shop and ask their opinion, what would be the best approach. I do have some access to a garage I could use to diagnose further myself, but time is very restrictive. Might end up buying another engine that could be used while this one is being remedied. Without pulling the head, it will be impossible to find out if it needs another bore, but here's to hoping a hone would suffice.  Goddamnit, I would really have preferred this not happening.  
    • 25RBGT
      Got this r31 silhouette flood car to rebuild.

      By 25RBGT · Posted

      Boot is going to be replaced eventually. I just wire brushed what I could and rust converted. Then painted in rust kill primer. the spoiler also got repainted and plugs replaced on the ends. The under side of the bonnet is going to be black also, currently white. But red on the top side, same colour code as the silo to begin.
×
×
  • Create New...