Jellybean Posted July 4, 2015 Share Posted July 4, 2015 (edited) Nightmare trying to get her back on the road, crank pulley went last week, fitted ATI today plus billet PHR pulleys Battery went flat, got her jumped via booster pack , left her to idle for about 10 mins , to give the battery a charge, took her outside, sitiing there she revved herself to 2k back to 700-1k then did it again 3 times in quick succession , then back to normal 5-600 rpm idle I just put it down to the ecu resetting, took her for a spin , she pulled fine to 1.2 bar mark , then on a 3rd pull it was like she hit fuel cut but not as violent then seemed fine after Took her back switched her off, went to take her home, turned her on , now she just revs to 2k rpm then back , constantly does this now, switched her off and she is running rich based on the smell of fuel Very strange, any ideas? Nothing electrical was touched in the car, just the crank pulley and aux pulleys, aux belt was changed, last week she was going like a train No engine codes , I was thinking resetting the ecu again Anybody experience this? I had the intake IC pipe off today, might be getting too much air? leak? Edited July 4, 2015 by Jellybean (see edit history) Quote Link to comment Share on other sites More sharing options...
mellonman Posted July 5, 2015 Share Posted July 5, 2015 Is the aircon on ? Not sure but it does raise and drop rpm Quote Link to comment Share on other sites More sharing options...
skippyboyo1 Posted July 5, 2015 Share Posted July 5, 2015 Is the aircon on ? Not sure but it does raise and drop rpm my aircon takes revs to 1500rpm Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 5, 2015 Share Posted July 5, 2015 MAP sensor issue? Personally, reading all your posts, I recommend petrol and a match for the thing Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 5, 2015 Author Share Posted July 5, 2015 MAP sensor issue? Personally, reading all your posts, I recommend petrol and a match for the thing It's the next step lol I would of taught a error code would be logged on the ECU if it was the map sensor Any way I can test it? Was going to check Intake intercooler pipe is on securely Cool pack clips and plugs Clien the Idle control valve Check all vacuum pipes Check sensors are secure Check ecu map sensor wire and harness is secure Anybody thing of anything else? Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 5, 2015 Author Share Posted July 5, 2015 my aircon takes revs to 1500rpm Will take a look, thanks Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 5, 2015 Author Share Posted July 5, 2015 Am I wasting my time , looking at Cam postion sensors TPS sensor Crankshaft sensor Quote Link to comment Share on other sites More sharing options...
TheTurtleshead Posted July 5, 2015 Share Posted July 5, 2015 Check your TPS sensor is adjusted properly, as per the manual with feeler gauges and a multimeter. Sounds like something mine did with an incorrectly set TPS. Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 5, 2015 Author Share Posted July 5, 2015 Thanks , what manual is it in ? was looking through them and cannot find it What would cause the TPS to need adjusting if it was not touched? Quote Link to comment Share on other sites More sharing options...
Bull3t Posted July 6, 2015 Share Posted July 6, 2015 I'm having exactly the same problem at the moment, but mine is blasting out black smoke, revving up to 2k then pretty much back to zero, then jumps back up to 2k again. Really worried it's going to cost me a bomb to fix it..... Quote Link to comment Share on other sites More sharing options...
The-Plethora Posted July 6, 2015 Share Posted July 6, 2015 I would check the idle control valve and clean it out with carb cleaner, it's not too hard but a bit of a sod to remove the screws. Are you sure your coil packs are ok? I had a problem on the old one where it would die when speeding up and eventually it died altogether. If it's still revs ok I would check that control valve first. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 6, 2015 Share Posted July 6, 2015 The symptoms would have me looking at FCD, MAP sensor, and associated wiring, or if it had any sort of piggy back ecu, removing it for initial testing. I would `scope the MAP sensor signal wire at the ECU, or at least measure the voltage relative to ECU ground. If that was OK I would start with basic tests like key on / engine off fuel pressure, then key on / engine on idling fuel pressure and progress from there. Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 6, 2015 Author Share Posted July 6, 2015 I reset the ECU,did a quick check of all vacuum lines, tested the Voltage going to the Map Sensor , mine is at 5V. I started her up, let her get to temp, she was running fine and after she warmed up , she idled at the 7-800 mark, turned her off then started her up again; then she went hunting 1-2K , et her run for a few mins and checked for any ECU error codes, she has error code 31 , Map sensor I also ruled out the ICV , I am fairly confident its the MAP sensor on mine, with regards the black smoke, thats her dumping in fuel to avoid a a lean condition, happened to me on track a few years back when my Map sensor plug came loose Map Sensor Voltage Test unplug it , hook up your volt meter , should be 4.5-5.5v between terminals VCC and E2 of the plug going to it (that's the outer two pins) with the ignition on. The test for the sensor itself I don't think is going to be very useful, because you have to disconnect the hose on the intake chamber side and apply a vacuum to it. Easier to just get a loan of a unit if you can Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 6, 2015 Author Share Posted July 6, 2015 Forgot to say, Thanks for the help guys! Will see if I can get a loan of a sensor , will post up my findings if it fixes the issue Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 6, 2015 Share Posted July 6, 2015 Has it got an FCD or piggy baback ECU on it? Suspect that, or wiring issues, the MAP sensors themselves are hugely reliable. The MAP sensor voltage you need to be looking at is the signal voltage FROM thr sensor, to the ECU. Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 6, 2015 Author Share Posted July 6, 2015 Has it got an FCD or piggy baback ECU on it? Suspect that, or wiring issues, the MAP sensors themselves are hugely reliable. The MAP sensor voltage you need to be looking at is the signal voltage FROM thr sensor, to the ECU. Mine has a SARD rom in the ECU with fuel cut raised to 1.3 bar , because the feed from the ECU to the sensor reads 5V I taught I could rule out wiring issue from ECU to the Sensor? I was looking at testing the Sensor but trying to test all the various engine conditions by supplying different Vacuum conditions seems very difficult to mimic, just going to get a loan of a sensor and try it instead Not too sure how I would go about creating a vacuum in the sensor? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 6, 2015 Share Posted July 6, 2015 The engine, when idling, will (should...) create a vacuum in the sensor. Ideally read the voltage at key on / engine off, and key on / engine idling, at the ecu, on the signal wire FROM the MAP sensor. Or at least read it at the MAP sensor signal wire itself, at the MAP sensor connector. At key on / engine off, the signal wire voltage should be higher than the voltage there with the engine idling. Both voltages should be well under 5V. Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 6, 2015 Author Share Posted July 6, 2015 thanks Chris The condition I tested the 5V under was the VCC and E2 terminals on the Map sensor Plug on the ECU loom with key on / engine off (I read there should be 4.5-5.5v) At normal atmospheric pressure it is supposed to be 3.3-3.9V. The voltage drop from normal atmospheric pressure when you apply a vacuum is supposed to be: 13.3 kPa 0.3-0.5 V 26.7 kPa 0.7-0.9 V 40 kPa 1.1-1.3 V 53.5 kPa 1.5-1.7 V 66.7 kPa 1.9-2.1 V I think the Test I need to do is key on / engine idling, measure the Voltage at ECU ; if it is working expect a low Voltage ? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 7, 2015 Share Posted July 7, 2015 Sounds about right, yes. Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 7, 2015 Author Share Posted July 7, 2015 Thanks Chris , might be able to get my hands on a sensor too They are 285 euro off Toyota Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 7, 2015 Share Posted July 7, 2015 It won't be the sensor, and they are dead easy to test anyway. Quote Link to comment Share on other sites More sharing options...
Ian C Posted July 7, 2015 Share Posted July 7, 2015 This behaviour is a sort of runaway engine control strategy, where the ECU is seeing the throttle is closed and the idle control valve is closed, but the engine RPMs still continually accelerate upwards. To preserve the engine it cuts fuel, then turns fuel back on when the revs have dropped. So it sits there cycling every couple of seconds between idle and about 2500rpm. I've had it myself years ago, but can't recall what caused it, but it's simple enough - the engine is getting way more air than it should be. Is the throttle butterfly cracked open but the TPS set to closed somehow? Is the idle valve stuck open? Is there an air leak somehow after the throttle butterfly, like a hose missing? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 7, 2015 Share Posted July 7, 2015 Yes, could well be a large air leak. On the engine side of the throttle butterfly. So MAP sensor hose off or leaking, or any other hose or gasket that applies to the TB, plenum or inlet manifold could be the source. I think the AIC will remain where it was electrically set if the connector is pulled off, or comes off, look there. PCV valve hose? PCV valve sticking? Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 7, 2015 Author Share Posted July 7, 2015 Thanks I had a check yesterday, everything looks good; all the Vacuum lines are new gates racing but on there a few weeks , she was running fine prior will run through it again today and check the ECU Voltage for piece of mind Only thing I can think of is the intake intercooler pipe was removed, checked it again yesterday and it is on secure Quote Link to comment Share on other sites More sharing options...
Jellybean Posted July 7, 2015 Author Share Posted July 7, 2015 So tested the map sensor connector again , 5v, key on engine off Now to the ecu, key on engine on, car idling Pin 62 turbo pressure sensor , black yellow wire Voltage was 1.64 for a few seconds, then fluctuates a lot around 0.3,0,35 then to zero, might spike to 1.64/1.63 What do you guys think Quote Link to comment Share on other sites More sharing options...
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