mikec Posted May 19, 2013 Author Share Posted May 19, 2013 Pretty sure the large pipe from the T piece to the TB is before the throttle flap so shouldn't be a problem anyway, and the system is set up to draw the correct amount through the small part of the t pieceUNLESS the large part is after the throttle flap in which case the lack of mushroom restrictor means that there is far too much air getting in to the inlet. Could be the issue. That's how it is, large part is before the butterfly. Quote Link to comment Share on other sites More sharing options...
mikec Posted May 19, 2013 Author Share Posted May 19, 2013 Wondering if its possible for there to be a leak in the servo? I've given up for today, its just about broke me, but ill have a try at blocking the pipe off for the servo tommorrow . Quote Link to comment Share on other sites More sharing options...
Rob_B Posted May 19, 2013 Share Posted May 19, 2013 Yes, the brake servo can leak. And if it isn't to bad it will still work but can mess up the engine idle. Disconnect the pipe and plug it. Just be careful when you drive it like that. Quote Link to comment Share on other sites More sharing options...
mikec Posted May 19, 2013 Author Share Posted May 19, 2013 Yes, the brake servo can leak. And if it isn't to bad it will still work but can mess up the engine idle. Disconnect the pipe and plug it. Just be careful when you drive it like that. Won't be driving it like that, I had a moment a couple of years back moving the 90 around, I only had to move it forward 4 feet, so thought ill save starting it up and push it, keep my hand on the brake pedal to stop it. Well Sod's law came into play, just as it rolled down the kerb the vacum was used up and it rolled into the back of my recently bought Astra. How I didn't burst a blood vessel still baffles me! :0 Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 20, 2013 Share Posted May 20, 2013 Right Been thinking about this The more I think the more I belive its not a megasquirt MSQ / VE ? Spark ? Set up issue, the more I think this is a mechanical problem within the engine setup itself, CAUSING MS to do odd things I am really now thinking this is an air problem, either via an air leak, which does seem to have been looked at so, if not that then I think it is an issue with the setup itself, either via the breather system or plumbing. Somehow I think additional air is either getting in / not getting in causing this hunting.. I also now think that there is a good chance logically that if there is some sort of "Air Issue" this can also showitself in the flat spot your saying you have, as I have untold numbers of peeps with the same MSQ as you have same setup and no issues So, piccie time please Take pictures of the engine, start with a "Helicopter view) and then go around the engine taking pics, make sure you get all the angles showing tubes and connections etc start from one side and go right around inc the rae Include air filter box, afm tune, all MS sensors, etc etc Lets have a good stare at whats there ............. We have to sort this hunting out before we go any further, its something serious as PWM normally controls say 50-100 RPM you have afr too much variance for "Normal" Nige Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 20, 2013 Share Posted May 20, 2013 ER !!!!!!!!!!!!!!!!!!!!!!!!!!!! KERCHIIIIIIIIIIIIIIIIIIIIIIIIIING ? Thats very very wrong The pipe should come FROM the drivers side rocker flame trap across the front of the plenum, then the T piece - one off the t piece forwards and the other to the plenum. DEFO not as it is now The passenger side should have NO tubes in it, it should have a filler plug and poss a small VENT at the rear This could be it Mikec !!! Sort it - air cicirulation is critical on V8s, I have no idea what you have connected to where but it is defo wrong, I have no idea as to what this set up you have will do, and also what other pipes go where etc ? where is the flame trap on the drivers side and where is that connected to ? Time to move rockers and pipes about chap Nige Nige Quote Link to comment Share on other sites More sharing options...
mikec Posted May 20, 2013 Author Share Posted May 20, 2013 Ill put the old Hotwire ones on and try it but I'm not sure, is there much difference between mine and the original setup except originally it took the breather from the pass side? Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 20, 2013 Share Posted May 20, 2013 Highly Likley as the system is designed with the flame trap to catch excess oil funmes and the hose arrangment to give PCV reset it to standard ......... Nige Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted May 20, 2013 Share Posted May 20, 2013 TBH I'm 50/50 as to whether that pipework makes a difference to the problem at hand... but it does confuse the issue and so really wants to be made standard just to eliminate the doubt. Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted May 20, 2013 Share Posted May 20, 2013 Or you could just blank it and let the breathers go to atmosphere? Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted May 20, 2013 Share Posted May 20, 2013 You might find that too much air is allowed through the big pipe because there is no mushroom filter, but I have mine set up with 6mm fitting instead of filter as do many and it is fine The breather setup to the left rocker cover won't make any difference as such, just air flows opposite way through crankcase to normal Hotwire operation. Try blocking or restricting the right hand breather inlet to attempt to disprove any breather theory, IMO the important part is that little restrictive T piece, the bigger pipe is for open throttle but would/could cause flat spot. Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted May 20, 2013 Share Posted May 20, 2013 Atmospheric breathing is probably no bad thing but I think PCV is better for oil health etc? Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 20, 2013 Share Posted May 20, 2013 Aye, and oily air into plenum can cause all sorts of issues Swap it around Mike, this is a sort via ruling out process Nige (and it doesn't involve HiRes Code, WB tuning, AE changes or Plucked chickens Thigh high boots and chanting postman pat at midnight )(Although in 6 months I'll suggest the chicken route if not sorted Wibble nige Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted May 20, 2013 Share Posted May 20, 2013 Plug the plenum connection and it will at least rule it out. Quote Link to comment Share on other sites More sharing options...
mikec Posted May 20, 2013 Author Share Posted May 20, 2013 Ok so just got in from swapping rockers, in typical mike fashion I spent nearly an hour trying to get the gasket to sit on the rocker cover whilst I got in position without taking anything else off, so in the end I took plug leads and alty wire off and within ten minutes it was on. Anyway fitted them on, got the pipework right for the drivers side, what happens with the pass side? There's a pipe connection with a tiny hole in it, that's just going to at,osphere at the minute??? So I took it out and it ran terrible! Obvioulsy I'd mixed two plug leads up haha :0 Sorted them went out again and it felt a little better, still kangorooing etc but just felt a bit better, maybe its just in my head! Only thing I noticed was I had trapped a wire in the passenger cover, noticed this because i could hear a hissing. So ill have to try it again either later or tomos and see what's what, as it was though idle was still hunting but sometimes would be ok. Quote Link to comment Share on other sites More sharing options...
mikec Posted May 21, 2013 Author Share Posted May 21, 2013 Well tried it tonight, only thing missing is the little mushroom breather on the pass rocker. Tried everything again, even replaced the hoses that t in from the fuel regulator and the plenum, just in case. Pics of engine bay to follow. Thanks mike Quote Link to comment Share on other sites More sharing options...
mikec Posted May 21, 2013 Author Share Posted May 21, 2013 Quote Link to comment Share on other sites More sharing options...
mikec Posted May 21, 2013 Author Share Posted May 21, 2013 Ignore that last one put that in by accident Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 21, 2013 Share Posted May 21, 2013 Er........ Rear of the plenum is a plate with a pipe sticking out towards the passenger side, this has to have a pipe connected to the matching pipe in the bulkhead side of the plenum where the butterfly is Sure these are well blocked off ? Also under the plenum where the tps is, on the basde should be a plate, where is that ? Also check all the holes under there if the plate is missing are all blocked up Now, If the above is yes they are blocked, what is the tickover like now, and what the best you can get aiming for a 880 RPM tickover by adjusting the butterfly screw in the plenum ?Nige Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted May 21, 2013 Share Posted May 21, 2013 Gotta find where that air is getting in when you block the TB with your hand! Gotta be that simple?! Quote Link to comment Share on other sites More sharing options...
mikec Posted May 21, 2013 Author Share Posted May 21, 2013 Er........Rear of the plenum is a plate with a pipe sticking out towards the passenger side, this has to have a pipe connected to the matching pipe in the bulkhead side of the plenum where the butterfly is Sure these are well blocked off ? Are you saying that a pipe needs to be connected now or on the original Hotwire setup? As it is now their well blocked off, those caps are fairly tight on, might just jubilee them anyhow. Plate under the tps is gone, I had to rtv three of the bolts back in on mine. Fourth was a blind hole. Tick over is still erratic, one second it's hunting the next it's not too bad, but trying to get it to 880 is a nuisance. It did seem to go a little better when I pulled the map pipe off the back and put my finger over it, but the revs also died down too, so that's probably a red herring. Quote Link to comment Share on other sites More sharing options...
mikec Posted May 21, 2013 Author Share Posted May 21, 2013 Gotta find where that air is getting in when you block the TB with your hand! Gotta be that simple?! Does yours stop when you do it Sam? Not sure if I've tried it or not, but it presumably runs on the air from the breather pipe. In fact I think it does, think I remember clamping the breather hose yesterday and covering the I take and it stopped. Though my brains that fried with this I can barely remember what my name is! Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 21, 2013 Share Posted May 21, 2013 Get the old pipe and connect the back of the plenum to the plenum so we know its properly sealed Air will find a route in if it can, and I still think it is Hand over TB and yes it should stop whilst sucking your hand in at the same time N Quote Link to comment Share on other sites More sharing options...
zardos Posted May 21, 2013 Share Posted May 21, 2013 (edited) I seem to remember somebody saying that one of the bolt holes for the throttle body heater plate actually goes all the way through in to the air intake, so if you don't have the heater plate on (or bolts in the holes) you will have an air leak there.I notice you have no heater plate? Fridge said it in http://forums.lr4x4.com/index.php?showtopic=81771&page=3&hl=%2Bplenum+%2Bheater#entry703018 Edited May 21, 2013 by zardos Quote Link to comment Share on other sites More sharing options...
mikec Posted May 21, 2013 Author Share Posted May 21, 2013 Get the old pipe and connect the back of the plenum to the plenum so we know its properly sealedAir will find a route in if it can, and I still think it is Hand over TB and yes it should stop whilst sucking your hand in at the same time N Ok pipe,on where the pwm pipes would go, once its warm it just revs its nickers off, about 1.5k revs at a guess. Tried turning. The throttle screw down to compensate but it has no effect. I'm still not sure on the hand over the tv theory, why would it not just run on the breather pipe through the crankcase? This is really starting to pee me off now, I'm not a patient man at the best of times but this is really trying my patience, I'm slowly getting to the point where I wish I'd kept the old engine and just plodded along Quote Link to comment Share on other sites More sharing options...
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