hodge Posted May 11, 2012 Author Share Posted May 11, 2012 Have you tried an uprated fuel pump or changed the fuel filter? (clutching at straws now like) I've fitted a brand new Walbro pump. It's not fuel restriction I'm sure of it, Quote Link to comment Share on other sites More sharing options...
hodge Posted May 11, 2012 Author Share Posted May 11, 2012 Here's a quick video I took a few days ago. http://i1103.photobucket.com/albums/g470/Shineypics/3bec1a4b.mp4 Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted May 11, 2012 Share Posted May 11, 2012 I would guess there's a big air leak somewhere, it's probably not the ICV valve doing that, the ecu is taking more stringent steps to control runaway idle speed, like shutting down the injectors. You need a scope.... What happens if you block the air intake with your hand when it's "idling"? What are the injector to head seals like? Pour a dribble of water around them when it's ticking over. A DRIBBLE, if it's a huge leak it may hydraulic the engine. This is why a Propane wand is best. Haven't you got a gas blowlamp? You can use that. Waft it around the intake, unlit, on full gas flow. If all else fails light the blowlamp and be rid of your irritation Quote Link to comment Share on other sites More sharing options...
Colin-mkiv Posted May 11, 2012 Share Posted May 11, 2012 Hmmm, that does sound like an air leak would be causing it, when the revs rise it doesn't sound strangled or anything. Do you have a large hammer? Quote Link to comment Share on other sites More sharing options...
hodge Posted May 11, 2012 Author Share Posted May 11, 2012 I think your right about an air leak but it seems to be a needle in a haystack. I'll remove the air filter and stick my hand over the intake and report back. I checked the injector seals when I had everything apart and all seemed fine. I'll get a gas blow lamp on Monday. How will I see where the air leak is while I move it around? Lighting it is an option BUT, the phone call afterwards would be worth recording and played on MR.T's worlds craziest fool. Ring ring, ring ring........ -Hiya mate -Alright John, how's the car coming along -yeah great mate, you can come pick it up it's all done, oh and bring a fire extinguisher and maybe a trailer cos I set fire to the fecker. -ok John, see you soon. -see ya. ..................... Think the call may go something like that lmao. I will get to the bottom of it though, it's certainly an interesting one, that's for sure. Quote Link to comment Share on other sites More sharing options...
hodge Posted May 11, 2012 Author Share Posted May 11, 2012 Hmmm, that does sound like an air leak would be causing it, when the revs rise it doesn't sound strangled or anything. Do you have a large hammer? It's not struggling for fuel, that I'm certain of. I've got a couple of things I want to try, but I'll be working on my own car tomorrow more than likely. Quote Link to comment Share on other sites More sharing options...
hodge Posted May 13, 2012 Author Share Posted May 13, 2012 Ok so, I may have found something. I was looking over the car briefly yesterday whilst waiting for the fibreglass to dry on my own car, and noticed that the the back plates that sit on top of the injector O-rings don't actually tough them on all the injectors. There seems to be a couple of mm gap between the O-ring and the plate. Odviously the O-ring have been crushed over time and now are too small. Now I'm not sure if this would cause an air leak, but it's a good place to start for sure. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted May 13, 2012 Share Posted May 13, 2012 You should be able to hear an air leak witha long piece of 1/4 bore tube to your ear. A butane or propane torch is easiest though. Or that dribble of water. Quote Link to comment Share on other sites More sharing options...
hodge Posted May 13, 2012 Author Share Posted May 13, 2012 Without sounding like a retard here Chris, BUT, what symptoms will I see if I move the torch over the leak? Quote Link to comment Share on other sites More sharing options...
hodge Posted May 13, 2012 Author Share Posted May 13, 2012 This is getting stranger by day. I fired the car today and blipped the throttle and it ticked over perfectly. I had it running for about 40mins no problems, was nice and smooth. I turned off the car and started it again and the revving started again FFS. This is making me think its an electrical fault and there is no air leak after all. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted May 13, 2012 Share Posted May 13, 2012 Air V Propane / other combustible gasses will show a big RPM change when introduced into a leak. Quote Link to comment Share on other sites More sharing options...
hodge Posted May 13, 2012 Author Share Posted May 13, 2012 Air V Propane / other combustible gasses will show a big RPM change when introduced into a leak. Okie dokie. I'll give that a go over the next couple of days. But to be honest because it's an intermittent fault I'm starting to sway towards an electrical fault. Quote Link to comment Share on other sites More sharing options...
Ian C Posted May 13, 2012 Share Posted May 13, 2012 Have you got any diagnostics/datalogging capability on your ECU? You could monitor the MAP sensor voltage, throttle position etc., see if they flick around to 0 or 100%, things like that indicative of a poor electrical connection. The stock ECU loom plug can get lose pins after being unplugged a lot, I did a tech thread on refurbing them a few years back Quote Link to comment Share on other sites More sharing options...
hodge Posted May 13, 2012 Author Share Posted May 13, 2012 Have you got any diagnostics/datalogging capability on your ECU? You could monitor the MAP sensor voltage, throttle position etc., see if they flick around to 0 or 100%, things like that indicative of a poor electrical connection. The stock ECU loom plug can get lose pins after being unplugged a lot, I did a tech thread on refurbing them a few years back It's just got a stock ECU Ian, so that's out I'm afraid. I've done a diagnostic on it and it comes up with nothing. If there's an issue with the igniter signal, could this have an effect on the pulsing of the revs. The reason I ask, is that, when I had the car running right, if I slowely raised the revs it got to about 3k and the rev counter went crazy and dropped off to almost zero but the revs themselves held fine. If I revved it quickly it seemed to go up the rev counter fine with a small twitch at 3k. I'm thinking along the lines of an issue with the igniter wiring or feedback signal wire. But again this could be a total different issue all together. Quote Link to comment Share on other sites More sharing options...
TheTurtleshead Posted May 13, 2012 Share Posted May 13, 2012 It's a 5 speed with an N/A to TT conversion, and the engine and ecu were originally from an auto correct? Does it sometimes cut out when stopping at junctions and dipping the clutch? Also, what is the rev limit in 4th when accelerating hard, and the rev limit in neutral when stopped? If it's low,5.5-5.8k I might know what it is. If not, then I can only suggest setting the TPS up properly with a multimeter and feeler guages if you haven't already tried it! Quote Link to comment Share on other sites More sharing options...
hodge Posted May 13, 2012 Author Share Posted May 13, 2012 I've swapped the ECU out for a 6 speed ECU. And yeah it was originally a 5 speed N/A with a TT conversion which has an auto loom. I've never had it on the road, ive been busy making the thing now a fire hazard and a death trap before I drove it What do you think the issue is? Quote Link to comment Share on other sites More sharing options...
hodge Posted May 14, 2012 Author Share Posted May 14, 2012 Ok, so, here's the issue. The car doesn't have a throttle control ECU, nor a connector for it. How I've overlooked this is beyond me. This engine WAS NOT removed from an auto supra as I was previously told. And this is how. This is a pic of my spare TT auto loom I use for spares. Notice the large ECU plug and the 2 smaller ECU plugs. The and 1 small one goes into the main engine ECU and the other smaller grey plug goes into the throttle control ECU. Now this is a pic of the ECU plugs for Simons car. There is 1 large grey plug and 1 smaller one which go into the main ECU and instead of having another grey plug it has this small white one instead, which odviously is the throttle ECU for whatever the hell it's came out of. My guess is that it's from a GS300 twin turbo. Here's a couple more pics of the plug. The way I see it, is there's 3 ways of doing this. 1) replace the loom for a Supra specific loom which I would preferr to do as this 1 is totally butchered. 2) try and find a throttle control ECU for the GS300 or whatever car it was removed from and give that a punt. 3) find the pin out's for both the supra and this other plug and hardwire a supra specific plug to it as I already have a supra throttle control ECU. This is proving to be a very, very interesting job for sure. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted May 14, 2012 Share Posted May 14, 2012 And one which perhaps warns some folk that N/A to TT conversions are not always a cheap way of getting a twin turbo engine in the car! Why people just don't save for a TT in the first place is beyond me. Quote Link to comment Share on other sites More sharing options...
mellonman Posted May 14, 2012 Share Posted May 14, 2012 surely finding the pin outs and hard wiring is the easiest route to sort out the idle, (but then you loose your spare plug) but i know what you mean by replacing the lot because god knows what else has been messed with and what condiction its in. Quote Link to comment Share on other sites More sharing options...
hodge Posted May 14, 2012 Author Share Posted May 14, 2012 Some of the wires are attached with speaker wire. It's a total butchered mess. Quote Link to comment Share on other sites More sharing options...
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