cainhead Posted April 12, 2019 Share Posted April 12, 2019 Hello, Just on my way to visit my sister in hospital when I noticed the car seemed to be over revving. It wasn't too apparent until i pulled up to some lights and the car was revving to about 2500 on its own. I check the pedal wasn't stuck and it was fine. I managed to get the car to the hospital. The AFR shows 10 whilst its revving as I guess the extra throttle is making it inject more fuel. I disconnected the battery just to see if the ECU (AEM V2) was having a funny five minutes but when tried to start it again it nearly fired but didnt until i pushed down a little on the gas pedal. I cant see anything in the engine like a disconnected pipe or anything but have noticed a very slight coolant drip from the main pipe right behind and just about the block. Could it be the idle control? Im pretty stuck as I cant leave the car here and i live about 7 miles away. Any ideas very much appreciated. Quote Link to comment Share on other sites More sharing options...
rider Posted April 12, 2019 Share Posted April 12, 2019 (edited) I'd start with the Throttle Position Sensor. The link gives a procedure with screwdriver, ohm meter and feeler gauges to test it out. Edited April 12, 2019 by rider (see edit history) Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 12, 2019 Author Share Posted April 12, 2019 I'd start with the Throttle Position Sensor. The link gives a procedure with screwdriver, ohm meter and feeler gauges to test it out. thanks for the link, thats a good start. Just a thought, is it common for this to just change mid drive? Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 12, 2019 Author Share Posted April 12, 2019 Just got the car home. Had a little look around and the throttle body and the the throttle stop lever (circled in picture) seems to have a lot of play. It spins and doesn't seem secure. I take it the throttle stop screw touches the lever pushing it down slightly when throttle is closed. I'll do the multi metre check in a second. Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted April 12, 2019 Share Posted April 12, 2019 You'd expect if it was holding revs at 2500 the AFRs would be at 14 odd, not 10, 10 is max boost full throttle stuff. Id say thats a start point Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 12, 2019 Author Share Posted April 12, 2019 Just got the car home. Had a little look around and the throttle body and the the throttle stop lever (circled in picture) seems to have a lot of play. It spins and doesn't seem secure. I take it the throttle stop screw touches the lever pushing it down slightly when throttle is closed. I'll do the multi metre check in a second. You'd expect if it was holding revs at 2500 the AFRs would be at 14 odd, not 10, 10 is max boost full throttle stuff. Id say thats a start point Sorry I don't follow. Are you saying the AFR is reading wrong therefore sending the wrong signal to the ECU. - - - Updated - - - Just got the car home. Had a little look around and the throttle body and the the throttle stop lever (circled in picture) seems to have a lot of play. It spins and doesn't seem secure. I take it the throttle stop screw touches the lever pushing it down slightly when throttle is closed. I'll do the multi metre check in a second. You'd expect if it was holding revs at 2500 the AFRs would be at 14 odd, not 10, 10 is max boost full throttle stuff. Id say thats a start point Sorry I don't follow. Are you saying the AFR is reading wrong therefore sending the wrong signal to the ECU. Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted April 13, 2019 Share Posted April 13, 2019 14 is the ideal fuel/air ratio, anything less than that, say 10 is rich, anything above that, say 16, is running lean. Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 14, 2019 Author Share Posted April 14, 2019 okay still pretty lost, the car starts really lumpy for about 10 seconds then smooths out and idles fairly normally, but AFR is constantly reading 10 until i blip the throttle and it rises to about 12 then goes back to 10. i connected the ecu to my tablet (standard aem software) and noticed with the engine off when i press the accelerator down the throttle percentage rises and falls as you would expect which says to me the ecu is getting a normal throttle reading. could the wide band sensor have gone? Why would the afr read as if im on full throttle/boost? Quote Link to comment Share on other sites More sharing options...
Style Posted April 14, 2019 Share Posted April 14, 2019 Sounds like a sticky idle control valve. Cars just pissing in fuel as it has no air control and can’t hit its targets? Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 14, 2019 Author Share Posted April 14, 2019 Sounds like a sticky idle control valve. Cars just pissing in fuel as it has no air control and can’t hit its targets? yes its firing out black smoke whilst it trying to settle so its certainly seems to be over fuelling. Just found a guide to cleaning the IACV so ill try that first Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 14, 2019 Author Share Posted April 14, 2019 yes its firing out black smoke whilst it trying to settle so its certainly seems to be over fuelling. Just found a guide to cleaning the IACV so ill try that first Managed to clean the IACV and no joy. It's there anyway to test these? Quote Link to comment Share on other sites More sharing options...
Style Posted April 14, 2019 Share Posted April 14, 2019 Managed to clean the IACV and no joy. It's there anyway to test these? Is the ECU showing anything for it when plugged in? I think it’s meant to make a clicking sound when you turn off the engine. Maybe see if you can hear it doing that to rule it in our out? Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 14, 2019 Author Share Posted April 14, 2019 Is the ECU showing anything for it when plugged in? I think it’s meant to make a clicking sound when you turn off the engine. Maybe see if you can hear it doing that to rule it in our out? Not sure on the clicking my exhaust is pretty loud (hks ti) plus it's in my garage so doubles the echo. Car is really spluttering and firing out a lot of black stuff. Quote Link to comment Share on other sites More sharing options...
Style Posted April 15, 2019 Share Posted April 15, 2019 Not sure on the clicking my exhaust is pretty loud (hks ti) plus it's in my garage so doubles the echo. Car is really spluttering and firing out a lot of black stuff. o2 sensor may be on the way out like you say. I'm having a sort of similar problem y'see so it would be good to get to the bottom of it for both our sakes lol Quote Link to comment Share on other sites More sharing options...
Sooty Posted April 15, 2019 Share Posted April 15, 2019 Could be a stuck open injector - you should be able to test the injector outputs with the ecu software. Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 15, 2019 Author Share Posted April 15, 2019 Could be a stuck open injector - you should be able to test the injector outputs with the ecu software. I had a look on the software and they all seem to be reading the same. They were brand new two years ago. Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 15, 2019 Author Share Posted April 15, 2019 o2 sensor may be on the way out like you say. I'm having a sort of similar problem y'see so it would be good to get to the bottom of it for both our sakes lol Im going to take the lamba and the AFR wide band sensor out and give then a clean. But also going to try my IACV from my other supra (should have tried that first really but stupidly didnt think) Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 15, 2019 Author Share Posted April 15, 2019 Okay cleaned lambda sensor, wideband, spark plugs and put in the IACV from my other supra. Started well, but AFR still reading 10. Let it run for a while and noticed I still have a small coolant leak above the back of the block from the pipe running out of the heater. Noticed lots of condensation coming out the back, so got it back into the garage and turned it off. Checked the oil cap and it seems to have the dreaded creamy shit under it. So fearing the worst. I cleaned the cap up put it pack on and started it again. Started a little groggy and lots of fuel smoke again, AFR reading 10. Turned it off and checked the oil cap again, same stuff even after i cleaned it. So i think the head gasket has gone, would all of my symptoms make sense. Then I guess i need to know whats the best way to test to confirm. Quote Link to comment Share on other sites More sharing options...
Style Posted April 16, 2019 Share Posted April 16, 2019 Compression test will be the best way to check the head gasket. Depending on how badly it's failed, I guess it could cause all sorts of problems. Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 16, 2019 Author Share Posted April 16, 2019 Compression test will be the best way to check the head gasket. Depending on how badly it's failed, I guess it could cause all sorts of problems. I have a little garage two streets away that have said they can do this, may just take it over to get a confirmation either way. Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 17, 2019 Author Share Posted April 17, 2019 can anyone tell me why after idle, then raising the revs to 2200 rpm and releasing the gas would it take a long time for the revs to return back to idle. Ive checked the TPS and i get the first and last readings but its a bugger to get to the terminals with a multi meter. Also can anyone confirm a jspec tt and uk tt TPS is the same unit. I may try the tps off my jspec to test. I still think i have a HG issue as the crap is still under the oil cap, however i dont get any overheating or bubbling of the coolant. Cars getting pressure tested today so will report back. Also after carefully looking through the aem software whilst connected i noticed the coolant temp seems really low. So just about to check that sensor as that could explain the rich AFR readings. Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 17, 2019 Author Share Posted April 17, 2019 Okay think I just found my issue. just went to test the coolant sensor and one of the wires came out of the clip right at the back so no chance of soldering. Must be just the age of the car. Tried to save the connector but whilst removing the prongs it crumbled. So any one know where to get a new connector, or is the sensor/thermostat a standard part i.e available from an autofactors Quote Link to comment Share on other sites More sharing options...
Scooter Posted April 17, 2019 Share Posted April 17, 2019 Looks like you need Coolant Temp Sensor 90980-11062 Taken from here, hats off the Andy for this work..... http://www.mkivsupra.net/vbb/showthread.php?232824-J-Spec-Engine-Harness-Connector-Details&highlight=connectors Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 17, 2019 Author Share Posted April 17, 2019 Is the ECU showing anything for it when plugged in? I think it’s meant to make a clicking sound when you turn off the engine. Maybe see if you can hear it doing that to rule it in our out? Yeah it's a great thread I've been reading through that for the coolant temp resistance. I just need to know if the temp sensor comes with the clip that plugs into it as that's what's broken, but will change sensor whilst I'm there Quote Link to comment Share on other sites More sharing options...
cainhead Posted April 17, 2019 Author Share Posted April 17, 2019 Yeah it's a great thread I've been reading through that for the coolant temp resistance. I just need to know if the temp sensor comes with the clip that plugs into it as that's what's broken, but will change sensor whilst I'm there Excuse my stupidy that part number is the clip Quote Link to comment Share on other sites More sharing options...
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