Fatboy Posted July 20, 2014 Share Posted July 20, 2014 Evening all, So, the 4.6 was built and fitted, with Megasquirt and MOT'd back in February.. I'm not very au fait with MS yet but wanted to get the motor running and figure it out on the way. The wagon ran for a while, then developed a miss-fire... I checked: Sparks from all eight plugs (Damn impressive sparks ) Signals to the seven injectors that I could reach - No.7 is hidden under the plenum chamber (Tested with a NOID light) Compression test - Seemed okay with all cylinders being similar (Although I did this by screwing the gauge in and starting the engine for a few seconds each time - This is bugging me that maybe that produces misleading results and I should have done it on the starter motor?) I then replaced the plugs "just in case", then the injectors - for the same reason. I went back to the original map that Nige sent... No change - she still has a grumpy, fairly consistent misfire. Then the work that pays the bills kinda took over and I've been away for quite a while. The garden has taken a chunk of reclaiming thanks to the Scottish climate but over the past few days I've decided to re-attack the 110. (July already!!!). I wondered if it might be an issue with the injector wiring so I made up a replacement section with long leads that I was simply going to feed through the door and plug into the relay board to see if that made any difference. However, when I removed the plenum chamber I noticed this patter on the underside..... It looks almost like oil vapour has been blowing up No.7 trumpet.... How on earth can that happen?? It doesn't look like it is coming from the rocker cover breathers so I'm kind of stumped..... I've taken the N/S rocker cover off and that all looks normal, I guess the next job is to whip the head off but I'd really appreciate thoughts if anybody has them! Thanks, Donald Quote Link to comment Share on other sites More sharing options...
Chazza Posted July 20, 2014 Share Posted July 20, 2014 Sounds nasty! I suggest the following: 1. Do a compression test using the starter motor. Do it hot and cold, wet and dry and record all of the observations and post the results here. 2. The only way oil can be getting through the inlet tract, is when it is pushed there by the piston with the valve open; therefore; oil must be getting past the piston rings, or through a hole in the piston. It can escape past the valve if the valve is burnt; or if the valve clearance is too tight; or if the inlet valve is sticking open; and without knowing the valve duration, possibly when the piston starts to come up on the compression stroke. 3. Oil can also get into the cylinder past the valve stem, but this would be unlikely to cause misfiring and it wouldn't be enough to blow up the inlet tract, it would probably be burnt before then. 4. I am guessing that No. 7 has serious piston/ring/cylinder wall wear. I am also alarmed at the colour of the oil; it should never be allowed to get that black. I change the oil on mine every 10 000km and the darkest it has ever become was a light tan. Dirty oil does not help piston rings, or the camshaft. Hopefully I am wrong and you can get out of this cheaply, Cheers Charlie Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 21, 2014 Share Posted July 21, 2014 Put it this way: I don't think that's a a software problem! Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted July 21, 2014 Share Posted July 21, 2014 Inlet valve not fully closing or broken. You did check the preloads when you fitted the cam/followers, right? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 21, 2014 Share Posted July 21, 2014 TSD has just looked over my shoulder and suggested something simpler: The injector is stuck open & it's blowing fuel up the port which is cleaning the existing oily residue off. 1 Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted July 21, 2014 Share Posted July 21, 2014 Yep certainly a possibility! Would expect the plug to be pretty wet after running like that though, and to kill the spark completely. Oh and the exhaust stinks like this, cos it is pumping out vapourised fuel rather than burnt, it makes your eyes bleed. Quote Link to comment Share on other sites More sharing options...
Fatboy Posted July 21, 2014 Author Share Posted July 21, 2014 Okay, to add a bit more info. The oil is on it's second change in less than 500 miles so it doesn't look black in the sump. I did check preloads and shimmed the pedestals accordingly. They are new injectors but that's an interesting thought.. I'll do a compression test this evening but it's looking likely that the head needs to come off for a peek at the valves / piston... Thanks for the thoughts so far! Quote Link to comment Share on other sites More sharing options...
SORNagain Posted July 21, 2014 Share Posted July 21, 2014 TSD has just looked over my shoulder and suggested something simpler: The injector is stuck open & it's blowing fuel up the port which is cleaning the existing oily residue off. Check the fuse in the plug before taking the back off the telly? Unless you want to take the head off of course.... Quote Link to comment Share on other sites More sharing options...
Bingy Posted July 21, 2014 Share Posted July 21, 2014 Inlet valve not fully closing or broken. +1 Quote Link to comment Share on other sites More sharing options...
Fatboy Posted July 22, 2014 Author Share Posted July 22, 2014 Indeed, I hadn't discounted FF's injector theory but they were replaced with brand new Bearmach ones and it made no difference. I'd also cleaned the inlets out when I built the engine so there shouldn't be that amount of crud to blow back up. I'll do the cranking compression test and if that is okay (seems unlikely now with the valve / piston pointers), I'll swap the injector and pop it back together.. If not, it's off with the head ? Quote Link to comment Share on other sites More sharing options...
Fatboy Posted July 22, 2014 Author Share Posted July 22, 2014 Dry compression test results: 1 - 12 bar 2 - 13 bar 3 - 12 bar 4 - 13 bar 5 - 12 bar 6 - 13 bar 7 - 13 bar 8 - 12 bar. A squirt or two of oil into the bore saw: 1 - 14 bar 3 - 13 bar 5 - 14 bar 7 - 14 bar And I'd also made an error, the clean patch is above trumpet 5, not 7. I don't have a jig or know-how to test the injector but could swap it for an old one to see.. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted July 23, 2014 Share Posted July 23, 2014 Remove the injector, if is duff you may well be able to blow through it. I would swap it out anyways. 1 Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted July 23, 2014 Share Posted July 23, 2014 Defo looks "Mecanical" and not a MS Issue... Injector would be my 1st thought, also changeplug as soaked plugs die fast ! Curious...looking forward to next installment 1 Quote Link to comment Share on other sites More sharing options...
Fatboy Posted July 23, 2014 Author Share Posted July 23, 2014 Haha... All new injectors fitted (2nd set!). New plug in no.5... I'm not convinced the miss fire has gone, it won't idle when cold now, low revs is still rough as rats but it barks when I hit the loud pedal. Seemed better once it had warmed up but by then my head was spinning and my eyes were on fire - it's running very rich I guess in the shut workshop.... I need to read up on tuning and find the data for my 4-hole injectors.. Set the basics and take it from there... Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted July 23, 2014 Share Posted July 23, 2014 Do a video of megatune screen when running...post up here Quote Link to comment Share on other sites More sharing options...
Fatboy Posted July 16, 2015 Author Share Posted July 16, 2015 So, this has been motivated by the "How to keep motivated on a project" thread and the realisation that it has been almost a year since the last purge on trying to get the 110 running properly... So, after I jet washed the leaves off it, this is what it looks like now: I've loaded one of Nige's base 4.6 maps, and tried a couple of others, its been to a Tuning Place in the big smoke because they told me they could handle Megasquirt but it was not really much different when it came back - It splutters but I think that is because its using a silly amount of fuel. i.e. I had it running last night for 10mins and the gravel behind was a darker colour behind the exhaust and smells of fuel.. I'm therefore coming to the conclusion that I must have something fundamentally wrong but I can't figure out what.. I have gone through the tips on Nige's most recent troubleshooting post and that all checks out (Air Temp is working, water temp is working etc etc). and tonight I'm back in the manuals and related threads.. Fingers crossed. Quote Link to comment Share on other sites More sharing options...
discomikey Posted July 17, 2015 Share Posted July 17, 2015 hopefully you get it sorted this time. It looks rather quite smart 1 Quote Link to comment Share on other sites More sharing options...
110 V8 Posted July 17, 2015 Share Posted July 17, 2015 Did you ever try the long injector leads through the window idea? Im picking a wiring fault (short to earth) on that injector. You say you checked pulses on all injectors except #7 as it was covered by plenum but im guessing you meant #5. Andy Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 17, 2015 Share Posted July 17, 2015 If it smells of fuel and uses loads of fuel is it by any chance running waaaay too rich? If you drown the lambda sensor in unburnt fuel it will read wrong (probably too lean) so listen to your nose Could be a stuck or mis-plumbed fuel pressure regulator or leaky MAP hose. Quote Link to comment Share on other sites More sharing options...
Fatboy Posted July 19, 2015 Author Share Posted July 19, 2015 Good call on the split MAP hose which is T'd off the vacuum hose for the fuel pressure regulator. I took the plenum back off to explore the idle screw and water flow.. I'll post photos later. Quote Link to comment Share on other sites More sharing options...
Fatboy Posted July 19, 2015 Author Share Posted July 19, 2015 So, I was confused by the various attachments on the plenum, and thought I'd investigate. To the right of the throttle position sensor is the IAC (Idle Air Control). When open, this allows air to be drawn in through the red hose. The drilled out plug on the top accesses the allen key which I thought was something to do with idle control and indeed it is, but only if you are using the IAC as it seems to regulate air flow past the valve. It does nothing with the throttle butterfly settings... I had wondered if the IAC valve was maybe jammed open, but it wasn't and now i can see it wouldn't have mattered because I've for the red hose plugged. I removed the IAC valve and blanked the hole... (I've fitted a PWM valve on the back on the plenum so wasn't planning on using the IAC, but maybe I should alter that plan?) You can see the allen screw (marked with a white dot) that controls the lower limit for the throttle linkage, and therefore the throttle butterfly. This has an allen head that can only be accessed from underneath, so to give me a bit of adjustment, I've turned this the other way up. It should give a nice solid stop, rather than using the adjustment of the throttle cable. Fridge was correct, the vacuum hose to fuel pressure regulator, that I've T'd off for the MAP hose was split at both ends.. Having put it all back together, my idle is now way too high, I've assumed that my previous maps were garbage so I had reloaded Nige's base 4.6 map and checked all of the basic settings. I disconnected my PWM valve, and blanked the hose, no difference. The throttle stop is as low as it was originally, and the cable not tight. Reset the TPS, which now has a lower setting of 14. To be honest, I'm baffled where it is getting the air from because the throttle butterfly must be shut... I wonder if the MAP vacuum is too low because of the 4mm bore of the hose and that is sharing with the fuel pressure regulator? (75kpa). Tomorrow, I'm going to put a temporary T on the brake vacuum hose to see if I get a better figure.. IIf anybody spots any howling errors, please holler! Quote Link to comment Share on other sites More sharing options...
Quagmire Posted July 20, 2015 Share Posted July 20, 2015 Are you bypassing the factory IAC valve and using an external pwm controlled one? You are right about the idle screw not moving the butterfly, what it actually does is allow air to go through a drilling the bypasses the butterfly completely. To get your idle down I would start with blocking your red hose off, and then adjusting the idle screw to get a good steady idle. The pwm valve can then only add air to that. At normal idle speeds you should get around 30-40kPa vacuum. Small bore pipe shouldn't cause you any issues. Quote Link to comment Share on other sites More sharing options...
Quagmire Posted July 20, 2015 Share Posted July 20, 2015 Just re-read you post. When you say you blanked the IAC, did you blank off the drillings inside or just remove it and put a plate over the hole where it went? Quote Link to comment Share on other sites More sharing options...
Fatboy Posted July 20, 2015 Author Share Posted July 20, 2015 I blanked the red hose, then put a plate over the face that the IAC bolts to.. Quote Link to comment Share on other sites More sharing options...
Quagmire Posted July 20, 2015 Share Posted July 20, 2015 You need to block the ports inside that chamber, there are two holes at 90 degrees to each other so that when the IAC retracts they can communicate and air passes through them. Look down there, you will see one hole at the bottom/end of the port and one on the left. With the plate on the outside these will still be open and will account for your high idle. Quote Link to comment Share on other sites More sharing options...
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