The Raven Posted October 18, 2012 Share Posted October 18, 2012 Yup i need help. I cant find the cause of the massive overfuel in my supra. I have a feeling its something stupid like a bad earth or a stuck something or another. I have tried most things inc change of ECU and it continues to chuck raw fuel out the back. Alas shes now been off road for a year. She has had so much work done to her that she now looks like a different car. Not that anyone has seen it! You may or may not have noticed that i have not posted alot of late. Even coming here makes me think about it and pees me off. So here is where i am. Shes tucked up in a lockup that is clean and dry. NO MOT so driving it to somewhere to get it looked at isnt an option. If anyone can help me find the issue i am more than willing to pay, kill, sell body parts just to be able to pass an MOT. The car is near canterbury in kent. Save MKIV your my only hope. Quote Link to comment Share on other sites More sharing options...
Josh Posted October 18, 2012 Share Posted October 18, 2012 Hope you get it fixed. Nothing worse than a problem you can't find/solve Quote Link to comment Share on other sites More sharing options...
Geo Posted October 18, 2012 Share Posted October 18, 2012 If you have a problem and no one else can help maybe you can hire the SRD TEAM. See what i did there, Quote Link to comment Share on other sites More sharing options...
Ian C Posted October 18, 2012 Share Posted October 18, 2012 Yay a challenge What diagnostics gear do you have available? Any of these?: Aftermarket ECU or piggyback thang with datalogging of injector duty Wideband O2 sensor Multimeter Fuel pressure sensor Oscilloscope (honest, if you've got access to one of these it'd be really useful ) These are the reasons you'll overfuel: 1) Fuel pressure higher than it should be (vacuum leak in reference hose, stuck FPR, blocked return hose) 2) Injector duty higher than what the ECU tells it to be (bad earth, sticking injectors, wrong impedance etc) 3) injector duty too high but the ECU thinks that's correct (bad O2 feedback, MAP, coolant or intake temp sensor bad, dodgy aftermarket fuel map etc) These are the reasons you'll think you're overfuelling: 1) Ignition misfire The absolute best first step in this process is to find out what the injector duty cycle is and compare it to a happy Supra. You'd need to know your injector size and your static fuel pressure as well. I've got a raft of hot and cold idle injector duty values across various sized injectors to compare your values with, so it'll be easy to see if that's the problem. Please tell me you've got an AEM or FCON or E-Manage or something -Ian Quote Link to comment Share on other sites More sharing options...
Ian C Posted October 18, 2012 Share Posted October 18, 2012 In fact, give us a rundown of the engine specs and any elerctronics bolted on, I checked your garage and the only supra in there is marked as Sold - - - Updated - - - Moved to tech and title tidied up a bit. Quote Link to comment Share on other sites More sharing options...
The Raven Posted October 18, 2012 Author Share Posted October 18, 2012 Ok. I brought the engine from a full running STOCK supra. I fitted it with the help of a few people. It started up ok but the icv needed cleaning. After which i was quite happy with myself as i watched what looked like steam coming from the back end. After a few more seconds the smell of petrol nearly killed us all. To my horror the floor was soaking wet with petrol. What ever is happening the Injects think they need to be on full chatter and just empty the fuel tank as fast as they can. Alas all i have is a Multimeter Your point 1. Seems to make sence and if im honest i have not checked the return hose! I never even thought about it! I wonder if i could have crushed it putting the engine in? I have a new rail with known good injects and fpr sitting here ready to go. Since all this started i have kind of lost my bottle and im now afriad to take things apart. Hence the offer to pay someone to help. Quote Link to comment Share on other sites More sharing options...
mellonman Posted October 18, 2012 Share Posted October 18, 2012 is this a N/A TT ? Quote Link to comment Share on other sites More sharing options...
The Raven Posted October 18, 2012 Author Share Posted October 18, 2012 Yes it is. Quote Link to comment Share on other sites More sharing options...
mellonman Posted October 18, 2012 Share Posted October 18, 2012 i take it you changed the loom and ecu's from the TT right i think it would be best if you put up your complete set up and history to help us fix your issue Quote Link to comment Share on other sites More sharing options...
jimojameso Posted October 18, 2012 Share Posted October 18, 2012 Get it trailored to somewhere and just get it sorted. As said take it to srd or austec. Quote Link to comment Share on other sites More sharing options...
The Raven Posted October 18, 2012 Author Share Posted October 18, 2012 I dont want to get it trailered somewhere if its a simple fix, Austec is a good 2 hours away atleast. The cost of trailering it there and back will probably out weigh the cost of the fix. Im sure Dude would take one look at it attach a wire or point to something and it will be fixed. The engine was brought as a stock TT lump that had never been BPUed. I serviced it and then fitted it to the shell. It came with everything i needed ECUs Loom gearbox ect. I checked everything even down to play in the turbo before fitting it. It cranked over fine and fired up well. Its idle was really rough so a clean out of the TPS sorted that out. The engine sounds fine with no clonks or bangs coming from it. The only issue i have is the fuel system. Quote Link to comment Share on other sites More sharing options...
mattdavies Posted October 18, 2012 Share Posted October 18, 2012 Did you say you have a spare fuel pressure reg ? i would change this and check the return line as mentioned by Ian C Quote Link to comment Share on other sites More sharing options...
Ian C Posted October 18, 2012 Share Posted October 18, 2012 Ok. I brought the engine from a full running STOCK supra. I fitted it with the help of a few people. It started up ok but the icv needed cleaning. After which i was quite happy with myself as i watched what looked like steam coming from the back end. After a few more seconds the smell of petrol nearly killed us all. To my horror the floor was soaking wet with petrol. Right, so you've converted from NA to TT and moved the lom and TT ECU over as well. Are the injectors now the j-spec 440cc side feed ones? Or UK spec 550's? What ever is happening the Injects think they need to be on full chatter and just empty the fuel tank as fast as they can. It probably wouldn't start if that were they case. And something would be locking them open or telling them to open too long for some reason. So let's look at the cause being faulty injectors. Chances of more than one stuck injector is slim to none, and just one stuck open would cause it to run on 5, but still run. It'd be rough, obviously. If it idles but does so lumpily, try removing the plug off each injector in turn, one at a time. It should get worse when you remove it and recover when you put it back. If there isn't a change, then that's the problem injector. Alas all i have is a Multimeter There are still things we can do for now Your point 1. Seems to make sence and if im honest i have not checked the return hose! I never even thought about it! I wonder if i could have crushed it putting the engine in? Easily tested. You can bridge +B and FP in the diagnostic port and then turn the ignition to position II (and mobilise the car if you have to). With the engine not running you should hear a rushing of fuel through the fuel rail etc., it's surprisingly loud. No rushing sound would indicate a problem with the return bumping the fuel pressure up massively. You can also remove the fuel tank cover plate in the boot and disconnect the fuel return hose there, stick it in a bottle and do the same test, see if you get a good strong flow of fuel. I have a new rail with known good injects and fpr sitting here ready to go. Since all this started i have kind of lost my bottle and im now afriad to take things apart. Hence the offer to pay someone to help. It's a very good idea to stop any further modifications and focus on fixing the current problem first, or you'll never know what caused it I'm assuming that, as I mentioned above, the currently installed rail and injectors are stock ones matched to the TT ECu you've put in? i.e. 440cc for j-spec or 550cc for UK spec? I'm not sure if the NA injectors are high or low impedance, but if you've swapped the entire loom out, that shouldn't matter as you'll have the right components for the injectors as part of the loom. Quote Link to comment Share on other sites More sharing options...
Ian C Posted October 18, 2012 Share Posted October 18, 2012 Also, get your multimeter on the signal wire of the MAP sensor while it's idling. You're looking at pin 62 (Black-Yellow) on the ECU or pin 2 (Black-Yellow) off the MAP sensor. If you see around 2.6v, it's reading wrong and probably has a leak in the vacuum reference as that's atmospheric pressure. You want to see around 1 to 1.5v at idle. Quote Link to comment Share on other sites More sharing options...
Ian C Posted October 18, 2012 Share Posted October 18, 2012 Also you say there is a strong smell of fuel and it was on the floor, is it actually coming out of the exhaust, or does the engine run okay and it's just a physical leak from a fuel line under the car? If you've got liquid fuel coming out of the exhaust pipe I wouldn't have thought it would even run, unless it's one bonkers injector doing it all - in which case your idle would be rough due to running on 5 cylinders, and you can diagnose which one using the steps I wrote above Quote Link to comment Share on other sites More sharing options...
The Raven Posted October 18, 2012 Author Share Posted October 18, 2012 Its coming out of the exhaust by the gallon load. You rev it and floods out. On idle is seems maybe a slight miss here and there due to flooding I will attempt all the fixes above, Many thanks Quote Link to comment Share on other sites More sharing options...
Nic Posted October 18, 2012 Share Posted October 18, 2012 Its coming out of the exhaust by the gallon load. You rev it and floods out. Definitely just petrol? If it's been stood condensation/water could have collected in the exhaust (shake the exhaust tail pipe and see if you can hear liquid sloshing around in the backbox)? If it is just petrol I'm surprised the car will even start. Quote Link to comment Share on other sites More sharing options...
The Raven Posted October 18, 2012 Author Share Posted October 18, 2012 Ive never seen anything like it. I will film it and show you it leaves puddles of fuel on the floor yet continues to run. Quote Link to comment Share on other sites More sharing options...
Ian C Posted October 19, 2012 Share Posted October 19, 2012 You haven't got one of those flamer kits that actually injects fuel into the exhaust have you? Quote Link to comment Share on other sites More sharing options...
Kristian_Wraae Posted October 19, 2012 Share Posted October 19, 2012 That sounds dangerous. If it is fuel it'll ignite in the exhaust at some point. I doubt it is fuel. If it is fuel then I can only imagine this can happen (with the engine running) if several cylinders are not getting ignition spark and even in that case I doubt fuel will run out of the exhaust. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted October 19, 2012 Share Posted October 19, 2012 Petrol does not go through a running engine, pass down the full length of the exhaust system on a road car, and then still remain liquid and drop on the floor. You need to get it somewhere with diagnostic gear and knowledge. Trailer it is the only option, if it' spewing liquid out the exhaust and running mad rich you have probably ALREADY done engine damage, it shouldn't be started again until some proper tests are done. Quote Link to comment Share on other sites More sharing options...
d_d Posted October 20, 2012 Share Posted October 20, 2012 Ive never seen anything like it. I will film it and show you it leaves puddles of fuel on the floor yet continues to run. A video would be a good start, could it not be a mix of oil and water. surely it would be smoking like hell also. for it to be petrol im sure it would evaporate quite quickly before exit Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted October 20, 2012 Share Posted October 20, 2012 You need to get it to a decent engine man, by whatever means. Quote Link to comment Share on other sites More sharing options...
The Raven Posted October 21, 2012 Author Share Posted October 21, 2012 It only runs for 30 seconds to see if anything i do fixes it. then i turn it off. Its losing no other liquids, its not oil or coolent. I know it needs an oil change when it does work I guess then i will have to find the cost of trailering and work. Probably be cheaper to send to Keron and get a engine swap than to pay to get someone to work on this lump. Quote Link to comment Share on other sites More sharing options...
The Raven Posted October 21, 2012 Author Share Posted October 21, 2012 Well seeing as i now have nothing to lose i went back to work on it today. I checked the O2, and the fuel return. Both where working. So now im swapping out the rail, injecs, and FPR. Quote Link to comment Share on other sites More sharing options...
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