and1c Posted March 19, 2016 Share Posted March 19, 2016 (edited) ok guys. I have a problem with the supra. Brief summary here. Single turbo approx 500 rwhp dyno dynamics. Link G3 LEM standalone, Walbro, 800cc sard injectors. When I bought the car it started and ran sweetly but had a cracked block because the owner hadnt put antifreeze in. So we fitted a known low miles GTE engine with arp hardware and other nice bits and after initially troubleshooting why it ran rich as a pig.. I got to the bottom of it (coolant temp sensor, and a few sensor wiring connectors damaged) and then I spent a lot of time going through the rest of the car sorting loads of other stuff . Its now at a nice standard after a lot of work but I took it to the bodyshop the other week and when I got it back, it wouldn't start... Took plugs out, fouled to hell with carbon and stinking of fuel (they had just been starting it and moving it in and out of the shop every day as its only a small shop) Its running pig rich and I cant find out what the issue is. It is not on the road at present so it is merely idling or micro runs. I am trying to get it all buttoned up to MOT it and get it on the road for Summer. I fitted an AFR gauge a while ago to help troubleshooting the rich running. Its about 10.8 at idle and when revved it goes to 14.7. Anyone got any ideas? I tweaked the cold start maps (for relevant temp points) in the Link and afr went to 12. But it still didn't like warm starting. Oil filler cap smells fuelly when opened. Im at a bit of a loss to find the issue. I've checked vacuum lines, all seem ok (they are silicone though..), same with boost pipes. ICV wiring harness looks tired, and unplugging it made no difference to the idle... but I have no test for the wiring harness and don't want to go down blind alleys!! Any ideas guys?? thanks Edited March 19, 2016 by and1c (see edit history) Quote Link to comment Share on other sites More sharing options...
Big Supes Posted March 19, 2016 Share Posted March 19, 2016 Have you checked the o2 sensors? As you're running an aftermarket ECU, you won't be able to use the diagnostics port, but maybe there's a way of checking with whatever software you're using? Quote Link to comment Share on other sites More sharing options...
Big Supes Posted March 19, 2016 Share Posted March 19, 2016 If the oil filler cap is smelling like fuel just be wary of borewash as that'll give you some nasty and very expensive issues. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 19, 2016 Share Posted March 19, 2016 I'd find a good Link mapper and have him look over it. I did have a quick look at the software on that car, and when I drove it it was running well. I wonder if it had stock or aftermarket cams in the cracked block engine? That could make a difference. Did it run the stoick MAP sensor on the cracked engine, or a different one? Are you running the same sensor on the "new" engine? Fuel pressure regulator the same? Injectors the same? Not sure what sensor outputs you can look at in the software, have you asked on the Link forums? It definitely ran fine when warm at one stage. Cold start and warm up were not brilliant though. You did keep a copy of the original map before fiddling....? Quote Link to comment Share on other sites More sharing options...
trebor69 Posted March 19, 2016 Share Posted March 19, 2016 I'd also check the coolant temp sensor again too. Quote Link to comment Share on other sites More sharing options...
Big Supes Posted March 19, 2016 Share Posted March 19, 2016 Worth checking all the boost pipes too (not sure if the body shop removed them and didn't refit them properly). Quote Link to comment Share on other sites More sharing options...
and1c Posted March 20, 2016 Author Share Posted March 20, 2016 Have you checked the o2 sensors? As you're running an aftermarket ECU, you won't be able to use the diagnostics port, but maybe there's a way of checking with whatever software you're using? Thanks mate. I don't think it is running an 02 sensor. It is custom downpipe, 4" exhaust etc. I fitted a PLX wideband O2 sensor to a blank plug on the downpipe but I believe not all standalones are setup with O2 sensor due to the fact they are mapped throughout the entire load range. Hopefully Chris can chime in on this though! I will check all the boost pipes top to bottom. I have found the alloy boost pipe has a large dent (where it joins to the samco connector) in where it comes up off the intercooler. It has clearly made significant ground contact (the car is low on coilovers). It still appears to be sealed fully to the silicone coupler but I will replace it in case. You make a good point about bore wash and this is something I am aware of. I am reluctant to run the car in any fashion until this is sorted, and I have not even been running it up until temp to see if it is ok since I got it back from bodyshop. I am dropping the oil from it today and putting fresh oil in before any further running tests. I'd find a good Link mapper and have him look over it. I did have a quick look at the software on that car, and when I drove it it was running well. I wonder if it had stock or aftermarket cams in the cracked block engine? That could make a difference. Did it run the stoick MAP sensor on the cracked engine, or a different one? Are you running the same sensor on the "new" engine? Fuel pressure regulator the same? Injectors the same? Not sure what sensor outputs you can look at in the software, have you asked on the Link forums? It definitely ran fine when warm at one stage. Cold start and warm up were not brilliant though. You did keep a copy of the original map before fiddling....? Cheers Chris for the help! Finding a guy who knows Links is proving difficult!! but I am in agreement with you that the car ran sweetly (not rich) with the old damaged engine and I have faith in the Link map as it ran the dyno dynamics at 490rwhp and it also hot started nicely for me before engine swap. The swap involved using a new block and bottom end with upgraded bits but mated to a full Toyota seals kit for the entire engine, and then the cylinder head, FPR , injectors and everything else from the old setup was cleaned and refitted (new injector seals etc). So I am as sure as I can be that the setup is identical to what it was before. The only thing I did find was that some connectors on the loom had bad connections after removal and refitting (wires gone brittle on entry to the connectors) and so I ended up going through all the ones I could see and repairing them with new wire, soldering iron and heatshrink. yeah that was fun! Car ran the stock G3 map sensor which is in the ECU on the old engine and this one is running the same one. I can view quite a few sensor outputs in the Link (not on a Syvecs level as it is an older ECU) but they all seem to be ok. I will get some screenshots once I have changed the oil and run it up. See if anyone can see the issue. I have several copies of the old map!!!! on different machines. I have only tweaked the cold start and temp correction tables, and not by much. They were at sensible levels after I compared them to the LINK G3 basemaps that Link give out for skylines and supras. I am convinced the issue lies elsewhere than the ECU. I just dont know where. I even compression tested the engine a while ago and readings were all 175-180psi. I'd also check the coolant temp sensor again too. Thanks mate. Does anyone have resistance readings that the sensor should be? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 20, 2016 Share Posted March 20, 2016 http://www.mkivsupra.net/vbb/showthread.php?238522-2JZ-sensor-resistance! Quote Link to comment Share on other sites More sharing options...
and1c Posted March 20, 2016 Author Share Posted March 20, 2016 http://www.mkivsupra.net/vbb/showthread.php?238522-2JZ-sensor-resistance! Thanks. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 20, 2016 Share Posted March 20, 2016 Have you got the one or two eyelet terminated engine to ECU grounds on, under the intake plenum? Not sure if the Link uses them, but if it does they are easy to forget. They go under 6mm thread bolts. Quote Link to comment Share on other sites More sharing options...
and1c Posted March 20, 2016 Author Share Posted March 20, 2016 Have you got the one or two eyelet terminated engine to ECU grounds on, under the intake plenum? Not sure if the Link uses them, but if it does they are easy to forget. They go under 6mm thread bolts. Cheers. This was one of the my initial issues. Car ran great after I had attached it .(ran rough as hell before!!!) I cant recall if there are two under there, will double check. Gone a bit rusty on it as the car has been at bodyshop for ages.. thanks chris Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 20, 2016 Share Posted March 20, 2016 Pretty sure there are 2 of them, they give the ground reference for the sensors, amongst other things, to the stock ecu. They probably used the same wires for the Link. You can check if the necessary grounds are on the stock ecu connector in the foot well, but I guess you will find one is still disconnected on the engine Quote Link to comment Share on other sites More sharing options...
and1c Posted March 20, 2016 Author Share Posted March 20, 2016 Cheers Chris. Will check this again. Pretty sure they are both on but will do anything at this stage. ! Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 20, 2016 Share Posted March 20, 2016 BTW, pretty sure the ECU is not (and may be cannot be mapped) using closed loop wide band. Don't think it even used a wide band at all. Can you measure the fuel pressure? Measure the MAP sensor output voltage relative to engine ground. is the MAP sensor definitely getting an unobstructed vac / pressure signal from the plenum? Quote Link to comment Share on other sites More sharing options...
and1c Posted March 20, 2016 Author Share Posted March 20, 2016 Thanks Chris. ECU can be mapped with wideband (I checked manuals and settings) but in this case I just have it hooked up to a gauge for my own diagnostics and AFR safety! Whats best way to measure fuel pressure? Is there a schraeder or some take off point on the stock TT fuel system?I will look into doing this today. Will also measure map and report back later on. Will have a few pictures as I have found a few connectors I am unsure of under the IM! thanks Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 20, 2016 Share Posted March 20, 2016 You need a long (double length) banjo bolt and a fuel pressure guage with a banjo fitting to tap the line in front of the fuel filter. Being single there will be some orphan connectors dotted about. MAP signal, coolant temp signal and air temp signal are likely causes of over fuelling if fuel pressure is OK. - - - Updated - - - You need a long (double length) banjo bolt and a fuel pressure guage with a banjo fitting to tap the line in front of the fuel filter. Being single there will be some orphan connectors dotted about. MAP signal, coolant temp signal and air temp signal are likely causes of over fuelling if fuel pressure is OK. Quote Link to comment Share on other sites More sharing options...
and1c Posted March 20, 2016 Author Share Posted March 20, 2016 (edited) You need a long (double length) banjo bolt and a fuel pressure guage with a banjo fitting to tap the line in front of the fuel filter. Being single there will be some orphan connectors dotted about. MAP signal, coolant temp signal and air temp signal are likely causes of over fuelling if fuel pressure is OK. - - - Updated - - - You need a long (double length) banjo bolt and a fuel pressure guage with a banjo fitting to tap the line in front of the fuel filter. Being single there will be some orphan connectors dotted about. MAP signal, coolant temp signal and air temp signal are likely causes of over fuelling if fuel pressure is OK. Thanks Chris. Appreciate the help. I will have to obtain a double banjo bolt and FPG as I dont have one currently. I'm not quite sure which line you are referring to. Both earths are attached under the IM, one by the dipstick bracket hole and the other further forward along the IM. Can anyone confirm what this is?? image free hosting Thanks guys Edited March 20, 2016 by and1c (see edit history) Quote Link to comment Share on other sites More sharing options...
and1c Posted March 20, 2016 Author Share Posted March 20, 2016 Ah yes, right, I was expecting to take the pressure from the fuel rail? Surely I want to be testing the FPR also>? Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted March 21, 2016 Share Posted March 21, 2016 The VSV, I think, its to do with the charcoal canister. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 21, 2016 Share Posted March 21, 2016 Ah yes, right, I was expecting to take the pressure from the fuel rail? Surely I want to be testing the FPR also>? You are testing the FPR at that point. Tank - Pump - Filter - Gauge - Rail - FPR - Return Line - Tank - - - Updated - - - The VSV, I think, its to do with the charcoal canister. Yes, you can ignore that. It's for purging the canister. Quote Link to comment Share on other sites More sharing options...
and1c Posted March 21, 2016 Author Share Posted March 21, 2016 You are testing the FPR at that point. Tank - Pump - Filter - Gauge - Rail - FPR - Return Line - Tank - - - Updated - - - Yes, you can ignore that. It's for purging the canister. Ah! Yes, makes sense. ok cheers Chris. Will update when I have the pertinent info in next few days. Thanks guys Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted March 21, 2016 Share Posted March 21, 2016 If it's a none OE FPR it may have a spare port on the inlet side to plug an adaptor and guage into. I would doubt the issue is too high a fuel pressure, as all was well before, unless you've fitted some monster pump in the interim? Too low is far more common. Quote Link to comment Share on other sites More sharing options...
and1c Posted March 21, 2016 Author Share Posted March 21, 2016 HI Chris. No, it is a stock FPR and the same in tank pump (Walbro I believe). Was thinking of fitting Aeromotive FPR and whiffbitz fitting kit for the stock rail. (with gauge) at least I could be sure that the FP was set right. But as you say, it was fine before and I have not changed anything related to fuelling. I am baffled at present... Also, I don't think it wise to add anything more than a guage or just measuring the pressure for now until this issue is sorted. Thinking it is most likely vacuum or the sensors you mentioned. Will check the air temp sensor as well and get a few screenshots of the Link screen. Will get that done now. Maybe that will give some clues!! thanks Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted March 21, 2016 Share Posted March 21, 2016 First off is the Link reporting any odd sensor readings IE not normal? I would double check the following, in no particular order, ECU coolant temp sensor (yes I know but it could also be faulty) Lambda sensor MAP sensor Fuel pressure Injectors or their seals for signs of leaking Air temp sensor wont cause that amount of richness as its quite a minor adjustment, and finally if the oil is smelling strongly of fuel don't push the engine and change it as soon as you find the fault, my favorite would be a stuck injector, or the injector seal is leaking. Quote Link to comment Share on other sites More sharing options...
and1c Posted March 21, 2016 Author Share Posted March 21, 2016 First off is the Link reporting any odd sensor readings IE not normal? I would double check the following, in no particular order, ECU coolant temp sensor (yes I know but it could also be faulty) Lambda sensor MAP sensor Fuel pressure Injectors or their seals for signs of leaking Air temp sensor wont cause that amount of richness as its quite a minor adjustment, and finally if the oil is smelling strongly of fuel don't push the engine and change it as soon as you find the fault, my favorite would be a stuck injector, or the injector seal is leaking. Thanks mate. I will go through this list tonight. The only one I can't check yet is fuel pressure. Does anyone know of a kit that works with stock fuel lines/filter etc. I cant find the size of the mythical double banjo Chris mentioned (M12 I think) nor a gauge that works with it. Think it would be easier to fit a new FPR on the rail and set it to factory pressure? or is that actually going to require a remap??? In that case I could just install a gauge? Quote Link to comment Share on other sites More sharing options...
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