# SR loosing power after an hour of running **URL:** \ **Category:** SON240sx Automotive\ **Created:** [September 12, 2012, 10:53pm UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921 "2012-09-12T22:53:51Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![MoNtAjNiK](https://avatars.discourse-cdn.com/v4/letter/m/d07c76/32.png) [@MoNtAjNiK](https://forums.speedlife.net/u/MoNtAjNiK)\ **Post date:** [September 12, 2012, 10:53pm UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/1 "2012-09-12T22:53:51Z")
If anyone has any idea, how could that happen , after about 40 mins of running, the SR engine does not respond to any, even small boost, the power is kinda falling down. When the gas pedal is pressed, the boost gauge shows , say 5psi, instead of picking up, the car runs flat, even weaker than when the throttle is less open. I do not have a wideband sensor, but would suppose it’s running really lean for some reason, as the boost is there, and since no power, the gas might not being injected. In my opinion, that could be two things, the alternator not supplying enough power to injectors, or ecu not functioning proper, what do you think? ---
**Author:** ![Steve660](https://avatars.discourse-cdn.com/v4/letter/s/ecb155/32.png) [@Steve660](https://forums.speedlife.net/u/Steve660)\ **Post date:** [September 13, 2012, 9:13am UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/2 "2012-09-13T09:13:58Z")
does it stutter and misfire or just no increase in rpm? Could be a lot of issues but making sure your ecu is getting enough juice is a good start. ---
**Author:** ![Nismo240SX](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/nismo240sx/32/5755_2.png) [@Nismo240SX](https://forums.speedlife.net/u/Nismo240SX)\ **Post date:** [September 13, 2012, 10:29am UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/3 "2012-09-13T10:29:05Z")
limp?? could be something with your temp sensor… ---
**Author:** ![MoNtAjNiK](https://avatars.discourse-cdn.com/v4/letter/m/d07c76/32.png) [@MoNtAjNiK](https://forums.speedlife.net/u/MoNtAjNiK)\ **Post date:** [September 13, 2012, 3:18pm UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/4 "2012-09-13T15:18:40Z")
It actually works fine, no stutter and misfire, just after the throttle is opened beyond certain point, it actually gives less power, and runs like non-turbo engine, while boost jumps to 5psi. How do I check whether the ecu sends enough power to injectors? As I understand, there has to be more power at higher rpm’s? > [@Steve660](#): > > does it stutter and misfire or just no increase in rpm? Could be a lot of issues but making sure your ecu is getting enough juice is a good start. ---
**Author:** ![Nismo240SX](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/nismo240sx/32/5755_2.png) [@Nismo240SX](https://forums.speedlife.net/u/Nismo240SX)\ **Post date:** [September 13, 2012, 3:47pm UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/5 "2012-09-13T15:47:03Z")
Oh ya there should be more power. Stock boost 7psi if you haven’t changed it. Might be your throttle position sensor if you say it’s when you hit the throttle. Try checking the tps. And you need to look at a sr20 Ecu pin out to check the injector drives and signals. ---
**Author:** ![G-E](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/g-e/32/5546_2.png) [@G-E](https://forums.speedlife.net/u/G-E)\ **Post date:** [September 13, 2012, 5:45pm UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/6 "2012-09-13T17:45:13Z")
wastegate is flopping wide open? clutch slipping? bov opening too low? ---
**Author:** ![MoNtAjNiK](https://avatars.discourse-cdn.com/v4/letter/m/d07c76/32.png) [@MoNtAjNiK](https://forums.speedlife.net/u/MoNtAjNiK)\ **Post date:** [September 13, 2012, 10:13pm UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/7 "2012-09-13T22:13:51Z")
> [@Nismo240SX](#): > > And you need to look at a sr20 Ecu pin out to check the injector drives and signals. Yep, how do I do that, can I measure it right at the injectors? If wastegate or bov would be open, then it should loose boost, but there is actually more, as the engine does not increase rpms that fast, and therefore is not consuming the air at faster rate. So, it’s most likely the gas supply, or less likely ignition timing. Since it happens gradually as the engine heats up, it might be a malfunction of something related to gas supply. ---
**Author:** ![Nismo240SX](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/nismo240sx/32/5755_2.png) [@Nismo240SX](https://forums.speedlife.net/u/Nismo240SX)\ **Post date:** [September 14, 2012, 7:56am UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/8 "2012-09-14T07:56:55Z")
[http://www.google.ca/imgres?imgurl=http://www.s-chassis.com/resources/wiki/images/6/60/ECUS13SR20DET.jpg&imgrefurl=http://www.240sxforums.com/forums/sr20de-det/118010-ecu-pinouts.html&h=672&w=828&sz=206&tbnid=QcuGUHjEEGuuNM:&tbnh=86&tbnw=106&prev=/search%3Fq%3Dsr20det%2Becu%2Bpinout%2B62%26tbm%3Disch%26tbo%3Du&zoom=1&q=sr20det+ecu+pinout+62&usg=\_\_4BCW9Id0vnluZJE1vfMpMUOpBko=&docid=oN4N6XpR8XInFM&hl=en&sa=X&ei=pkRTUK-0OcqZyQHhq4GIAg&sqi=2&ved=0CDUQ9QEwAg&dur=877](http://www.google.ca/imgres?imgurl=http://www.s-chassis.com/resources/wiki/images/6/60/ECUS13SR20DET.jpg&imgrefurl=http://www.240sxforums.com/forums/sr20de-det/118010-ecu-pinouts.html&h=672&w=828&sz=206&tbnid=QcuGUHjEEGuuNM:&tbnh=86&tbnw=106&prev=/search%3Fq%3Dsr20det%2Becu%2Bpinout%2B62%26tbm%3Disch%26tbo%3Du&zoom=1&q=sr20det+ecu+pinout+62&usg=__4BCW9Id0vnluZJE1vfMpMUOpBko=&docid=oN4N6XpR8XInFM&hl=en&sa=X&ei=pkRTUK-0OcqZyQHhq4GIAg&sqi=2&ved=0CDUQ9QEwAg&dur=877) look here…and u need 2 people, one to check the pinout voltage and one to crank it… it could be a number of things and more then one problem. fix one at a time. check the ecu and make sure its functioning in all pinouts. i dont think its boost related. borrow someones wide band, a friends, or i have one also with a long ass wire so all we do it swap the sensor…or buy one cause they are very very helpful… ---
**Author:** ![karkas9](https://avatars.discourse-cdn.com/v4/letter/k/f14d63/32.png) [@karkas9](https://forums.speedlife.net/u/karkas9)\ **Post date:** [September 14, 2012, 9:32am UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/9 "2012-09-14T09:32:32Z")
you can check continuity with battery to injectors and then the ecu ground to ecu, then get a light bulb with high resistance and hook it to you injector harness see if it flickers. an normal average multimeter cant really determine if the ecu is grounding your injectors on any rpm. that being said check your compression when hot with throttle fully open then if anything abnormal do leak down test. my bet is on you coils over heating thu. check your spark plug gaps. gap that is more than the oe spec would cause more temp in the coil. ---
**Author:** ![MoNtAjNiK](https://avatars.discourse-cdn.com/v4/letter/m/d07c76/32.png) [@MoNtAjNiK](https://forums.speedlife.net/u/MoNtAjNiK)\ **Post date:** [September 14, 2012, 11:32am UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/10 "2012-09-14T11:32:47Z")
Thanks for that diagram, really useful ---------- Post added at 02:32 PM ---------- Previous post was at 02:31 PM ---------- > [@karkas9](#): > > my bet is on you coils over heating thu. check your spark plug gaps. gap that is more than the oe spec would cause more temp in the coil. That sounds more real, should look into ---
**Author:** ![randy240sx](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/randy240sx/32/5740_2.png) [@randy240sx](https://forums.speedlife.net/u/randy240sx)\ **Post date:** [September 15, 2012, 12:59pm UTC](https://forums.speedlife.net/t/sr-loosing-power-after-an-hour-of-running/225921/11 "2012-09-15T12:59:25Z")
sounds like coils to me!!