Guest Draven Posted July 2, 2006 Share Posted July 2, 2006 I'm a little stumped here, so any suggestions are more than welcome. Took the car to get dynoed today. First dyno run it made 174rwkw before, according to the operator, it "hit some kind of cut" - 30km/hr before it should have. after that run, driving it home, I tested out the problem. It seems that whenever the second turbo kicks in (above 4000rpm), the car goes into a sort of "snow mode" (although the light doesn't come on), and I lose all boost. Even a quick change to a new gear so I'm below 4000rpm will not spool the first turbo, and it feels underpowered even for no boost. This *only* happens above 4000rpm when the second turbo would kick in. 4th gear it will happily spool up the first turbo to its max boost, so I don't think it's a load issue. Any suggestions on what may be the cause guys? Link to comment Share on other sites More sharing options...
Guest Draven Posted July 2, 2006 Share Posted July 2, 2006 additional info: it has a slight miss at idle. It's also not breaking traction doing it, and no trac or snow lights flashing at me Link to comment Share on other sites More sharing options...
mikeyb10supra Posted July 2, 2006 Share Posted July 2, 2006 do you have a FCD, was traction control off?? just checking....unlikely if there were no dash lights? could be a misfire, does it lurch forwards when it cuts power? Im banking on spark plugs mate...when were they last out? Link to comment Share on other sites More sharing options...
Guest Draven Posted July 2, 2006 Share Posted July 2, 2006 it's a very smooth loss of power. boost just dies and trails right off, and won't make it for a while below 4000rpm. The car is totally bog stock - no fcd, no boost controller, nothing. spark plugs have *just* been replaced. I have fingers crossed the vvti TT uses the same sparks as the non-vvti? Someone has suggested that my second turbo is dead, and all my exhaust gas is venting through where my 2nd turbo exhaust wheel used to be, but it has less power than 0 boost after losing boost at 4000rpm, plus the second turbo was working on the dyno until it hit "cut", and dyno operators didn't report any noises suggesting exhaust wheels lodged in my cat - and since it has standard exhaust, it's actually quite quiet Link to comment Share on other sites More sharing options...
Fifty Posted July 2, 2006 Share Posted July 2, 2006 If I were you Id reset ECU and check all pipework for leaks In particuklar check the IC pipes. Im a non -tech but just IMHO. Rich Link to comment Share on other sites More sharing options...
mikeyb10supra Posted July 2, 2006 Share Posted July 2, 2006 I have fingers crossed the vvti TT uses the same sparks as the non-vvti? No Probs there mate Someone has suggested that my second turbo is dead, and all my exhaust gas is venting through where my 2nd turbo exhaust wheel used to be, but it has less power than 0 boost after losing boost at 4000rpm, plus the second turbo was working on the dyno until it hit "cut", and dyno operators didn't report any noises suggesting exhaust wheels lodged in my cat - and since it has standard exhaust, it's actually quite quiet not a chance, you would have bellows of black smoke if your turbo had gone... Could be VSV valve problems, im no expert on the sequential system, but I would suggest getting the 2nd valve checked....the one where the first turbo shuts off and the second start to operate? Link to comment Share on other sites More sharing options...
mikeyb10supra Posted July 2, 2006 Share Posted July 2, 2006 If I were you Id reset ECU and check all pipework for leaks In particuklar check the IC pipes. Im a non -tech but just IMHO. Rich he is hitting boost on turbo one, so not likely to be a leak, but worth a look anyway....no harm is there....and agree with the ECU reset Link to comment Share on other sites More sharing options...
Guest Draven Posted July 2, 2006 Share Posted July 2, 2006 yeah, turbo 1 is very happy, not matter the throttle position, speed, load, whatever - so I'm doubting it's an i/c leak (although I have just had them off, so I will double check) Will reset the ecu (again) - I just had the battery out for 3 days when I changed the timing belt, but worth double checking. Any other suggetions? Link to comment Share on other sites More sharing options...
Fifty Posted July 2, 2006 Share Posted July 2, 2006 loose coil pack connectors? - fairly common when plugs are changed? couldnt get 30 mph out of my TT when this happened to me. Rich Link to comment Share on other sites More sharing options...
Guest Draven Posted July 2, 2006 Share Posted July 2, 2006 I should add, the 2nd turbo not boosting is the only problem apart from the slight miss at idle. it happily boosts the 1st turbo in 1-4th gear (didn't try 5-6), it drives smoothly at this boost, it drives fine at higher rpm as long as I'm careful not to light up the turbos Link to comment Share on other sites More sharing options...
Steviekid Posted July 2, 2006 Share Posted July 2, 2006 I should add, the 2nd turbo not boosting is the only problem apart from the slight miss at idle. it happily boosts the 1st turbo in 1-4th gear (didn't try 5-6), it drives smoothly at this boost, it drives fine at higher rpm as long as I'm careful not to light up the turbos If the second turbo isn't coming online then chances are the valves opening it up aren't working properly. Check the IACV and EGCV, the vaccum hoses supplying their actuators and corresponding VSVs first, then investigate the pressure tank. Link to comment Share on other sites More sharing options...
Guest Draven Posted July 2, 2006 Share Posted July 2, 2006 but most importantly, would this cause the first turbo to stop making boost at the same time? I'm trying to drain you guys of information before morning here, when you'll all be at work, or sleeping, or something Link to comment Share on other sites More sharing options...
Steviekid Posted July 2, 2006 Share Posted July 2, 2006 but most importantly, would this cause the first turbo to stop making boost at the same time? No, problems with the IACV/EGCV operation generally would not affect the first turbo. There is nothing stopping the first turbo spinning up so other than a boost leak or the wastegate sticking open it should boost ok. What boost are you getting with the first turbo? Link to comment Share on other sites More sharing options...
Guest Draven Posted July 3, 2006 Share Posted July 3, 2006 it starts off boosting to full, then when the second turbo is supposed to come on it loses all boost, and doesn't even have the usual power of driving it not hitting boost. I'm stuck between shredded exhaust wheel and stuck wastegate at the moment... but (with my limited knowledge of the 2j turbo setup) I would still think the 1st turbo would make some kind of boost in both situations, which makes me wonder if the computer is picking up on something and cutting my boost and throttle response (because it really does feel like TRAC/snow mode, throttle response is lessened as well as boost) Link to comment Share on other sites More sharing options...
Guest Draven Posted July 3, 2006 Share Posted July 3, 2006 right well I pulled my sparks (again) today, and found that my #4 spark has a bent electrode. http://www.users.bigpond.net.au/draven/supra/bent_plug.jpg Last time the car had a problem, the #5 plug had a bent electrode http://www.users.bigpond.net.au/draven/supra/sparks.jpg what on earth could be causing me to bend spark plugs? It's also possible the engine bay felt hotter than usual (but that could just be me thinking that - temp guage was normal) Link to comment Share on other sites More sharing options...
Guest Draven Posted July 11, 2006 Share Posted July 11, 2006 well guys, from what I can tell I shat out the 2nd turbo's exhaust wheel, which is why I loost boost when it comes on. I have a feeling turbine wheel fragments arealso responsible for the destruction of my spark plugs. My solution will involve a gt35/40 Thanks for all the help across various topics Link to comment Share on other sites More sharing options...
wkdtime Posted July 11, 2006 Share Posted July 11, 2006 Sorry to hear that mate, on the plus you can go bigger, better, faster! Link to comment Share on other sites More sharing options...
Thorin Posted July 11, 2006 Share Posted July 11, 2006 I still would have thought you'd be getting a lot of black smoke/death whine if your second turbo was shafted. As for the plugs "bending" I guess this could happen if you had sky high EGT's. Link to comment Share on other sites More sharing options...
letmeshowyou Posted July 11, 2006 Share Posted July 11, 2006 is this diagnosis conclusive? It still sounds like an EGBV problem to me (as I'm also surprised at the lack of smoke and noise). If the EGBV isn't working (or working intermittently) Turbo 2 wont come on, and turbo one actually does show a drop off in boost, as its fighting a restriction that shouldnt be there. I had the exact same problem on mine when I got it, as a mouse had chewed through an EGBV hose! Do you get any turbo chatter? Link to comment Share on other sites More sharing options...
chilli Posted July 11, 2006 Share Posted July 11, 2006 the exhaust wheel fragements can't get into the engine surely, these would be blown out the exhaust? only the compressor blades would get sucked in, and if they did and resulted in bent sparkplugs I'd be very worried they hadn't also done damage to the bores and pistons! lets hope it is nothing as severe as this! Link to comment Share on other sites More sharing options...
Ian C Posted July 11, 2006 Share Posted July 11, 2006 You could suck exhaust wheel fragments back into the cylinder due to backpressure and reversion but you'd have to be unlucky. However the stockers do create a lot of backpressure and are very close to the cylinders so there is more chance of it than with say a freer-flowing exhaust, a single turbo, and a long runner tubular manifold. Mind you if anything twatted into the plug anode I thing you'd see it a LOT more bent than that. I think that's going to be a different phenomena causing the plug anode being bent a bit towards the cathode. (I think I've got anode and cathode the right way round there ) -Ian Link to comment Share on other sites More sharing options...
Guest Draven Posted July 12, 2006 Share Posted July 12, 2006 well, the symptoms seem to match turbo #2 not spooling, as I'm losing all boost when #2 should come on (all boost generated by #1 is just going straight through #2 the wrong way) it could be an EGBV problem, but all the hoses are checked and double checked, so the actual unit would have to have failed. I converted the car to TTC briefly to see what would happen, and I got no boost at all. and since this is my last post due to trial period etc (and me being a poor uni student with 2 280+rwhp supras), I'd just like to say thanks again for all your help! Link to comment Share on other sites More sharing options...
geoffvalenti Posted July 12, 2006 Share Posted July 12, 2006 and since this is my last post due to trial period etc (and me being a poor uni student with 2 280+rwhp supras), I'd just like to say thanks again for all your help! This is the type of attitude that is destroying society today. Take, take, take until you're required to put something back, then disappear, and milk some other poor saps for knowledge. We should have sent him over to the tumbleweed forum, they need the members even if they are a bunch of leeches. If you can't afford to pay £10 for membership, Draven, you haven't got a cats chance in hell in running a Supra. And please, don't give us the old hard up student routine, we've heard it too many times before, for it to pull on our heart strings Link to comment Share on other sites More sharing options...
Darren Posted July 12, 2006 Share Posted July 12, 2006 right well I pulled my sparks (again) today, and found that my #4 spark has a bent electrode. [qimg]http://www.users.bigpond.net.au/draven/supra/bent_plug.jpg[/qimg] Last time the car had a problem, the #5 plug had a bent electrode [qimg]http://www.users.bigpond.net.au/draven/supra/sparks.jpg[/qimg] what on earth could be causing me to bend spark plugs? It's also possible the engine bay felt hotter than usual (but that could just be me thinking that - temp guage was normal) Those spark plugs dont all look the same type? Link to comment Share on other sites More sharing options...
Guest Draven Posted July 12, 2006 Share Posted July 12, 2006 ok, I could afford it but choose not to. I'm already a financial member of 2 local toyota/supra clubs, and my usual way of giving back to international clubs is through tech contributions to the forums - I simply can't afford to join every supra club I post to. and yes, they're 2 different sets of spark plugs. I changed them all after 1 died Link to comment Share on other sites More sharing options...
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