PeteMck Posted December 31, 2018 Author Share Posted December 31, 2018 Passenger side (the one the drill bits pointing at) Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted December 31, 2018 Share Posted December 31, 2018 Ah yes, different on that plenum, I forget how it is supposed to be, will look up later. Any chance you have excessive crankcase pressure? Quote Link to comment Share on other sites More sharing options...
PeteMck Posted December 31, 2018 Author Share Posted December 31, 2018 Well I'm not gonna rule anything out but it's a brand new recon engine so I hope not! Lol. How can you tell if there's excessive pressure? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 1, 2019 Share Posted January 1, 2019 Remove that hose and check for excessive puffing, but if a new engine,don't worry about it Quote Link to comment Share on other sites More sharing options...
PeteMck Posted January 1, 2019 Author Share Posted January 1, 2019 Phew. So why would clamping that pipe help? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 1, 2019 Share Posted January 1, 2019 If there is an air leak into the crank case. So... On that note, what is the disptick seal like? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 1, 2019 Share Posted January 1, 2019 Does that drill bit seal properly? Quote Link to comment Share on other sites More sharing options...
PeteMck Posted January 2, 2019 Author Share Posted January 2, 2019 Drill bit has been replaced with proper pipework now. Dipstick seal is pretty good. Quote Link to comment Share on other sites More sharing options...
PeteMck Posted January 4, 2019 Author Share Posted January 4, 2019 Still struggling to find the vacuum leak. It actually idles pretty well until it gets up to temp then it wants to be around 1000rpm to run well. Have checked the butterfly valve in the plenum and that seems fine. Could it be the seals where the butterfly valves connects to the throttle linkage and tps sensor? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 4, 2019 Share Posted January 4, 2019 Yes, I ha e had that cause problems before, about £15 to refurb from memory. The left hand breather, where it connects to the plenum, is that restricted in the same way as the right hand one? Quote Link to comment Share on other sites More sharing options...
PeteMck Posted January 4, 2019 Author Share Posted January 4, 2019 I can't remember if it is or not. It enters in front of the butterfly valve though I think. I've changed the valley gasket today as now working my way up and the rocker covers seals as well. One thing I did notice this morning is that when starting from cold it idles well until it starts to warm up and only really starts hunting when it's up to temp. Don't no if that helps narrow down the causes. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 4, 2019 Share Posted January 4, 2019 Sorry, getting my left and rights mixed up! The right hand breather, but guess you have answered that one... I went to a 3.9 setup, which links the two breathers into one port. Is the top end all 4.0 stuff, or a mixture? Quote Link to comment Share on other sites More sharing options...
PeteMck Posted January 5, 2019 Author Share Posted January 5, 2019 Everything is 4.6l stuff apart from the exhaust manifolds which are 4.0l Quote Link to comment Share on other sites More sharing options...
PeteMck Posted January 6, 2019 Author Share Posted January 6, 2019 Right, had the tps sensor off and the stepper motor out. Tried blanking off the stepper motor but it just started reving to 2000 on idle so put it back. Is it possible I've got an air leak around that internally? Quote Link to comment Share on other sites More sharing options...
PeteMck Posted February 11, 2019 Author Share Posted February 11, 2019 Right, slight update. Ive got another plenum and tried that incase I had an air leak where I'd put all the pwm pipe work on or incase I had a leak around the throttle housing and still got the same problem. Starting to run out ideas as to where to look for an air leak. 😖 Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted February 11, 2019 Share Posted February 11, 2019 I haven't read back through this but by blanking off the stepper do you mean actually blocking the air passage or just blanking the place where the stepper goes? Need to break this down methodically bit by bit to rule stuff out. Quote Link to comment Share on other sites More sharing options...
PeteMck Posted February 16, 2019 Author Share Posted February 16, 2019 Yer well I was wondering if I had a leak with the plenum (blanking plugs, throttle housing, stepper motor wasnt shut fully, where I had mounted niges pwm pipe outlet etc) so put another plenum on and still got the same problem. I can find any air leaks anywhere incl rocker cover pipes, changed valley gasket, rocker cover gasket, I've blocked off the brake servo pipe incase that was leaking and it's still wanting to idle around 1000rpm Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted February 16, 2019 Share Posted February 16, 2019 What did you do with the old stepper to make sure it is closed? The one behind the drill bit in recent pic? Quote Link to comment Share on other sites More sharing options...
PeteMck Posted February 16, 2019 Author Share Posted February 16, 2019 Errr just assumed it was fully shut in its 'resting' position. From memory they are sprung arnt they? Either way the other plenum had it's own one in and still the same issue. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted February 16, 2019 Share Posted February 16, 2019 Nope. You need to do something with it, this is 99% likely your problem.... Quote Link to comment Share on other sites More sharing options...
PeteMck Posted February 16, 2019 Author Share Posted February 16, 2019 Hmm when you say do something? Just start poking it with some electricity and see what happens? Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted February 16, 2019 Share Posted February 16, 2019 No, remove and work out how to plug the hole. It's a stepper motor, so poking with 12v won't do anything. Quote Link to comment Share on other sites More sharing options...
PeteMck Posted February 17, 2019 Author Share Posted February 17, 2019 Hmm any suggestions on how to plug it? 🤔 Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted February 17, 2019 Share Posted February 17, 2019 I don't remember what it looks like behind there, over to you I am afraid Quote Link to comment Share on other sites More sharing options...
Quagmire Posted February 17, 2019 Share Posted February 17, 2019 I seem to remember that the stepper allows air from a port coming in from the main throat of the plenum (concentric to the stepper hole) to take a 90 degree turn through a small port on the inboard side. You'll need to jam something in to block both holes- I think I wrapped a drill bit in insulation tape until it was a snug fit when I set my base idle. This was all quite a while ago though so I may be talking total piffle. Quote Link to comment Share on other sites More sharing options...
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