ok so my sr has been acting up on me lately and i was wondering if anyone could explain to me what can be causing these problems:1.idle seems to move around alot liek go up to 1200 back down to 900 and keep going up and down(my idle used to be at 750 before)
2.it never seems to warm up when idleing it barely warms up when i drive it and then the temp drops out of nowhere (possible collant temp gauge and ECU sensor problem?)
3.it runs really rich most of the time and alot of my friends say they can smell it when they are behind me.
im thinking possible vacuum leak somewhere sorry for the newb questions im trying to get my car to my first drift event on the 27th and i want everything to be good to go. thanks guys!
Fluctuating idle and motor never warms up
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Team_Undisputed
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duffman1278
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Team_Undisputed
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Re: (duffman1278)
cool thanks for the reply man:bigthumb do you happen to have a layout of all the vacuum lines on a S13 SR? oh and how do i check to see if i have leaking injectors?(i.e. visual check or pull it out and check it)duffman1278 wrote:Sounds like either a vacuum leak, or your IACV is really dirty. Also seems like leak injectors.
Re: (Team_Undisputed)
A vacuum leak would lean it out while cruising and only slightly, certainly no worse than what BOV valve float lets in if vented to atmosphere. The RPM's may try to break up while boosting as well.
Try disconnecting your O2 sensor and see if there's much of a change in the way it runs. The rich condition and unstable idle sound to me like it's running open loop, which is what happens when the O2 sensor goes bad.
Also verify the throttle position sensor voltages.. a bad one will mess with idle but im not sure how much it effects air/fuel, since its purpose is to help the ecu calculate engine load. The maf, O2 and temp sensor help the ecu calculate injector duty.
About your temp gauge, are you using the gauge cluster temp sender from your KA?
Modified by Neil at 1:15 PM 9/16/2008
Try disconnecting your O2 sensor and see if there's much of a change in the way it runs. The rich condition and unstable idle sound to me like it's running open loop, which is what happens when the O2 sensor goes bad.
Also verify the throttle position sensor voltages.. a bad one will mess with idle but im not sure how much it effects air/fuel, since its purpose is to help the ecu calculate engine load. The maf, O2 and temp sensor help the ecu calculate injector duty.
About your temp gauge, are you using the gauge cluster temp sender from your KA?
Modified by Neil at 1:15 PM 9/16/2008
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Team_Undisputed
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Re: (Neil)
so all should do is disconnect the connecter from the o2 sensor and start the engine also yeah i have a gauge cluster from a dual cam KA. is the gauge cluster not working correctly?? cause everything else works fine(fuel meter, RPMs, etc.)Neil wrote:About your temp gauge, are you using the gauge cluster temp sender from your KA? Modified by Neil at 1:15 PM 9/16/2008
haha sorry for the title man i already changed my thermostat a couple of weeks ago and it helped it a little bit but not muchHijacker wrote:Sounds more like the thermostat is busted. The coolant is freely flowing, and your motor never gets to operating temp. When motors are cold, they run naturally rich.
Also, here's a pro-tip. NAME YOUR THREAD TITLES! Nobody can search accurately when your threads are titled "LOL. I have a problem"
oh and today i was letting my car idle and then i noticed a little bit of smoke coming from the turbo area... and then i rev to see if more would come out and then it comes out of the turbo and the exhaust...blown turbo?? but from what i read a blown turbo means that it should smoke at idle but no smoke only when i rev up... i took it for a test drive and no more smoke when driving, idle or revving it up is this normal?? i PRAY that it isnt a blown turbo my first ever event is coming up in 11 days!!!
Modified by Team_Undisputed at 6:43 PM 9/16/2008
Re: (Team_Undisputed)
i didnt mean to confuse you, I didnt mean use a different gauge cluster, I meant use the KA temp sender for your cluster.
There's 2 coolant temp senders on the motor (right next to each other, I'm not certain which is which, unfortunately), one is for the ECU, the other is for the temp gauge in the gauge cluster. It's been a few years since I did my swap but I believe you need to use the GAUGE temp sender from your KA in the SR or else your temp gauge won't read properly.
As for the O2 sensor, yes- just unplug it while the motor is running and see if it runs/drives any worse. If there is no real change then I'd begin troubleshooting from that area by first verifying the sensor's output voltage at its pin on the ECU plug. If it reads 0, double check your work if you had to lengthen the O2 sensor wires. If you find a problem and it still reads 0 or only runs marginally better, replace the O2 sensor.
My car ran the exact same way, and I found a couple problems while troubleshooting. My throttle position sensor was full of water, causing its readings to fluctuate randomly. Also I was getting 0v to the O2 pin on the ECU, which was a result of my being a noob and splicing the shielding (shielding is a metal mesh sleeve around the wire jacket that and reduces electromagnetic interference) to the core wire when I lengthened that bit of the harness. Since the shielding is grounded I was grounding out the O2 sensor, and that's why my ECU saw 0v.
If you unplug the O2 sensor, it forces the ECU to run 'open loop' and consequently overly rich, as you have described. If you disconnect the O2 sensor and see no change, that would indicate something is making the ECU run open loop, such as a bad sensor or a wiring mishap like what I did. If you disconnect the O2 sensor and it runs even worse, try using someone else's MAF. Also cam angle sensors can cause some bugged out drivability / power making issues but not so much as to make your car have a lumpy fluctuating idle while puffing little clouds of soot.
Replacing the throttle position sensor didn't do much more than let me get the ignition timing set properly, but that's important too.
As for the smoke, you shouldn't see any exhaust fumes coming from around the turbo area. Not unless smoke is coming out of the tailpipe and you have a major exhaust leak at the turbo. My guess is it's just grimy fingerprints burning off, or if you painted your manifold or anything then it's just the paint cooking, and that will eventually stop. If you replaced the turbo gaskets and used a thin layer of RTV of the wrong temp range then any of the squeeze out will burn off and probably smoke too.
Modified by Neil at 9:57 PM 9/21/2008
There's 2 coolant temp senders on the motor (right next to each other, I'm not certain which is which, unfortunately), one is for the ECU, the other is for the temp gauge in the gauge cluster. It's been a few years since I did my swap but I believe you need to use the GAUGE temp sender from your KA in the SR or else your temp gauge won't read properly.
As for the O2 sensor, yes- just unplug it while the motor is running and see if it runs/drives any worse. If there is no real change then I'd begin troubleshooting from that area by first verifying the sensor's output voltage at its pin on the ECU plug. If it reads 0, double check your work if you had to lengthen the O2 sensor wires. If you find a problem and it still reads 0 or only runs marginally better, replace the O2 sensor.
My car ran the exact same way, and I found a couple problems while troubleshooting. My throttle position sensor was full of water, causing its readings to fluctuate randomly. Also I was getting 0v to the O2 pin on the ECU, which was a result of my being a noob and splicing the shielding (shielding is a metal mesh sleeve around the wire jacket that and reduces electromagnetic interference) to the core wire when I lengthened that bit of the harness. Since the shielding is grounded I was grounding out the O2 sensor, and that's why my ECU saw 0v.
If you unplug the O2 sensor, it forces the ECU to run 'open loop' and consequently overly rich, as you have described. If you disconnect the O2 sensor and see no change, that would indicate something is making the ECU run open loop, such as a bad sensor or a wiring mishap like what I did. If you disconnect the O2 sensor and it runs even worse, try using someone else's MAF. Also cam angle sensors can cause some bugged out drivability / power making issues but not so much as to make your car have a lumpy fluctuating idle while puffing little clouds of soot.
Replacing the throttle position sensor didn't do much more than let me get the ignition timing set properly, but that's important too.
As for the smoke, you shouldn't see any exhaust fumes coming from around the turbo area. Not unless smoke is coming out of the tailpipe and you have a major exhaust leak at the turbo. My guess is it's just grimy fingerprints burning off, or if you painted your manifold or anything then it's just the paint cooking, and that will eventually stop. If you replaced the turbo gaskets and used a thin layer of RTV of the wrong temp range then any of the squeeze out will burn off and probably smoke too.
Modified by Neil at 9:57 PM 9/21/2008