Seany boy Posted July 21, 2013 Share Posted July 21, 2013 Basically , car started burning oil and producing blue smoke so stripped her down for a full rebuild. Renewed all the gaskets etc/rings, honed it and what not. Put it back together , refitted it this weekend aaaaand won't run. Cranks but that's it, please read my tale and help me before I cry So the engines in, wired / plumbed etc but it won't run, This is what happened ... Fitted engine , tried to sart it and it cranks no problem but wouldn't run. After numerous checks and petrol cans it started but wouldn't idle ... After a few more attempts I got her started and could rev it (only to 1500-2k so no high rev chaos) and hold it there,but if I let the revs drop below 1200 it would stall. After this it wouldn't idle / start ,just cranking. After LOTS of head scratching and checking it had a spark / fuel (it had both at this point) we checked cam timing and that was fine, last resort was the flywheel not being timed correctly so pulled box it off and it wasn't on the timing marks. Removed / refitted it and now I have a engine that cranks fine but no spark and no fuel, no error codes but I can't get a live feed from my local garage. Any thoughts ? Quote Link to comment Share on other sites More sharing options...
rtbiscuit Posted July 21, 2013 Share Posted July 21, 2013 Something hasn't been plugged back in? Quote Link to comment Share on other sites More sharing options...
ioneabee Posted July 21, 2013 Share Posted July 21, 2013 any spares left over - you know "savings" - maybe they need to actually go back on Quote Link to comment Share on other sites More sharing options...
Seany boy Posted July 21, 2013 Author Share Posted July 21, 2013 Checked every plug / sensor and there all connected and fairly idiot proof. Can't understand how it ran (badly, but ran) then wouldn't , now after aligning the fly correctly iv lost spark and fuel ? Quote Link to comment Share on other sites More sharing options...
Mopedmark Posted July 21, 2013 Share Posted July 21, 2013 At this point all you can do is re check all that you have plugged back in but can't understand why no eml lights are not on there is Google Quote Link to comment Share on other sites More sharing options...
rtbiscuit Posted July 21, 2013 Share Posted July 21, 2013 Are they new plugs or the old ones, could it be bad coincidence one of the plugs is on its way out? Quote Link to comment Share on other sites More sharing options...
Seany boy Posted July 21, 2013 Author Share Posted July 21, 2013 I had no fault codes so to check the ecu was actually working unplugged the crank sensor and it came on straight away with the fault. Brand new plugs aswel but I tested the plugs / cool packs (all of them) this morning when I was still getting a spark Quote Link to comment Share on other sites More sharing options...
rtbiscuit Posted July 21, 2013 Share Posted July 21, 2013 My guess is its something straight forward that you've missed, but as I'm not there looking into the engine bay its difficult to suggest what it is. Can you run through your reconnection sequence when you were putting it all back together. Quote Link to comment Share on other sites More sharing options...
gareth29 Posted July 21, 2013 Share Posted July 21, 2013 I'm sure I read some where on the us website 350z tech that said that "even nissan technicians" had problems getting rebuilt engines to run properly if everything wasnt connected up/set up perfectly before starting. Did you disconnect the battery after you refitted the flywheel? Just thinking that you may have confused the ecu if you didnt? Quote Link to comment Share on other sites More sharing options...
bpmjames Posted July 21, 2013 Share Posted July 21, 2013 Make sure all the earths are connected. I missed one from the ecu loom on a Nissan engine once and it wouldn't start. Could be a faulty maf sensor? Had it been dropped? Did u touch the filament? Is it plugged in? Sent from my C6603 using Tapatalk 2 Quote Link to comment Share on other sites More sharing options...
jumping350 Posted July 21, 2013 Share Posted July 21, 2013 When i had similar symptoms ended up being a grounding point ,maybe check and clean all the main ones Quote Link to comment Share on other sites More sharing options...
Seany boy Posted July 21, 2013 Author Share Posted July 21, 2013 Reconnection - With a rebuilt block fitted exhaust/engine mounts/water pipes/main harness/ancillaries/fitted engine into the car/plugged harness into passenger footwell/connected plugs in the bay/water pipes/earths. Ref the earth iv tried running a jump cable fr the block to the body as a earth and made no diff Ref the maf. It was never removed from the pipe, took filter off with it attached and it sat in the boot for 3 months lol Ref the battery being unplugged, yeh iv disconnected it 4x since, even tried the reset method (disconnect and touch the cars + - wires together for 30 seconds to discharge everything) Il try the earths tomorrow / unplug and replug all plugs. It's such a headache tho ! Currently abandoned looking like this , Quote Link to comment Share on other sites More sharing options...
bpmjames Posted July 21, 2013 Share Posted July 21, 2013 Re the earths: Jumper cables won't work if one of the ground from the ecu isn't connected. I'm taking about the type of ground that is connected to the engine from a loom with something like an m6 ring crimp bolted to some part of the engine. Normally intake manifold or around that area. They are really easy to miss and also to overlook when searching for a problem. Sent from my C6603 using Tapatalk 2 Quote Link to comment Share on other sites More sharing options...
Darren-B Posted July 21, 2013 Share Posted July 21, 2013 Check the Earth from the ignition loom, its the one that bolts on with 10mm nut onto the timing case cover on the front. Theres a certain member, mentioning no names that got a little green over this after he had painted the timing cover & insulated the connection This one Quote Link to comment Share on other sites More sharing options...
Seany boy Posted July 22, 2013 Author Share Posted July 22, 2013 Where am I looking specifically for these grounds ? I know about the one on the front cover and il sand the paint off it for a better earth, any others ? Like say everything else works, just won't run Quote Link to comment Share on other sites More sharing options...
Ekona Posted July 22, 2013 Share Posted July 22, 2013 Working through this logically, and please correct me if I'm wrong: First it cranked over but wouldn't fire (possibly indicating no fuel or spark, did you check at the time?) Then it did fire, however wouldn't stable idle (possible air leak) Stopped firing, fuel and spark confirmed Flywheel refitted correctly, fuel and spark lost Is that the correct sequence of events? If so, then it should be something you've done between removing the gearbox to sort the flywheel and replacing it. It cannot be anything else logically, for you to lose both spark and fuel. I don't know if they're on a shared ground at any point, or if there is a cable that's unplugged (or possibly trapped and damaged somewhere?). Of course, cars are funny things and it could be something completely different, however I would start by unplugging and reconnecting every plug you can see that could be connected to this. That's ECU, cam sensors, injectors, coil packs, the lot. It'll take a while, but it's also pretty easy to do and at least it rules out a bad connection. Quote Link to comment Share on other sites More sharing options...
Seany boy Posted July 22, 2013 Author Share Posted July 22, 2013 When it 1st cranked and wouldn't fire we blamed lack of fuel, so I put 10litres in and it eventually fired. Once I had it running I kept it at 2k then as I let the revs drop it died and wouldn't fire again. The following day it fired 1st time but wouldn't idle, wouldn't fire again after this. I checked the plugs and they were soaked in petrol, after cleaning them I checked every plug and they all sparked, then every coil pack with the same results so definitely had petrol/spark. After head scratching decided the fly was out of time and as a result the engine was fuelling at the wrong time so was soaking the plugs. After changing the flys position I have lost spark an fuel. Don't know if there's a earth for the ecu that lives on the box but il check all earths / plugs after work Quote Link to comment Share on other sites More sharing options...
gareth29 Posted July 22, 2013 Share Posted July 22, 2013 silly question but i assume you have to have no.1 cylinder at tdc (compression) before you set the flywheel position? - no chance you have it set at tdc (exhaust)? did you remove the fly to do the work on the cylinders? Quote Link to comment Share on other sites More sharing options...
Seany boy Posted July 22, 2013 Author Share Posted July 22, 2013 Yeh checked tdc on #1 before attacking the fly. So I have a spark and file again (earth issues,cheers guys) cars Trying to start but still won't. Done a compression test and we have a new problem .... Left bank is 100% perfect if not better, Right bank... Low. Not sure how low but 1-3-5 are are equally as low. He thinks the VVT sprocket might e to blame? Basically when it got stripped to be rebuilt the apprentice took the 4 bolts out the vvt instead of the centre bolt. Thinking he may have put it back together incorrectly , would this affect compression / running ? Quote Link to comment Share on other sites More sharing options...
gareth29 Posted July 22, 2013 Share Posted July 22, 2013 that may be a factor - the manual warns you specifically never to remove those - but I'm not quite sure what goes on inside those sprockets! Quote Link to comment Share on other sites More sharing options...
Seany boy Posted July 22, 2013 Author Share Posted July 22, 2013 Compression test results.. 1-150psi 2-150psi 3-50psi 4-150psi 5-50psi 6-150psi What the hell ?!?! Quote Link to comment Share on other sites More sharing options...
bpmjames Posted July 22, 2013 Share Posted July 22, 2013 Damaged rings? Is there and oil on the plugs? Smell of fuel in the oil when u remove the dipstick? Valves lapped in correctly? Does the vq35 use hydraulic lifters? We're they primed before u put them in? Sent from my C6603 using Tapatalk 2 Quote Link to comment Share on other sites More sharing options...
Seany boy Posted July 22, 2013 Author Share Posted July 22, 2013 Brand new rings , no smell off oil , just petrol since the plugs are soaked in it. Could the vvt sprocket have been put back together in the wrong way at all? Can't understand why #1 still makes 150psi and 3/5 make 50? Oil is clean / waters clean so don't think it's head gasket. No leaks either Quote Link to comment Share on other sites More sharing options...
gsexr Posted July 23, 2013 Share Posted July 23, 2013 Are you sure that the cams are timed up correctly ? Who put it back together.....the apprentice ? Just a thought as the spark no spark could be a second issue but you need to know its timed up correctly first. Quote Link to comment Share on other sites More sharing options...
Seany boy Posted July 23, 2013 Author Share Posted July 23, 2013 It's timed correctly according to the timing marks but all I can think is if the Vvt sprocket isn't back I'm correctly then the marks for that cam could be out by 90'/180'/270' since it can only bolt on 1 of 4 ways. Just don't understand how 1 cylinder on that bank could still make 150psi and the other 2 50psi. Ref the timing , I let x2 master techs time it up for me, it confuses the crap out of me lol Quote Link to comment Share on other sites More sharing options...
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