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can't adjust idle because of ECU interference.
I have a 98. I can't adjust the idle because the ECU keeps turning it back down, or up.
I tried turning that big plastic screw method to up my idle a bit. It worked for like 30 secs, then the idle self adjusts and comes down. Several years ago, I even went to the dealer to raise my idle. They even connected the OBDII tool(dont know if it Consult II) to try to raise the idle, but it didnt work. Well, it did work for like 10 min, but the idle always went back down to factory setting. What could be causing this? Anyone had similar problems? I would like to raise the idle to around 800, because now with my budget ypipe, when I'm sitting in traffic with the AC on, the car vibrates a bit. |
Re: can't adjust idle because of ECU interference.
Originally posted by hokiemax I have a 98. I can't adjust the idle because the ECU keeps turning it back down, or up. I tried turning that big plastic screw method to up my idle a bit. It worked for like 30 secs, then the idle self adjusts and comes down. Several years ago, I even went to the dealer to raise my idle. They even connected the OBDII tool(dont know if it Consult II) to try to raise the idle, but it didnt work. Well, it did work for like 10 min, but the idle always went back down to factory setting. What could be causing this? Anyone had similar problems? I would like to raise the idle to around 800, because now with my budget ypipe, when I'm sitting in traffic with the AC on, the car vibrates a bit. |
Re: Re: can't adjust idle because of ECU interference.
Originally posted by iwannabmw What procedure did you use to adjust the idle? Was the TPS disconnected? |
Re: can't adjust idle because of ECU interference.
Originally posted by hokiemax I have a 98. I can't adjust the idle because the ECU keeps turning it back down, or up. I tried turning that big plastic screw method to up my idle a bit. It worked for like 30 secs, then the idle self adjusts and comes down. Several years ago, I even went to the dealer to raise my idle. They even connected the OBDII tool(dont know if it Consult II) to try to raise the idle, but it didnt work. Well, it did work for like 10 min, but the idle always went back down to factory setting. What could be causing this? Anyone had similar problems? I would like to raise the idle to around 800, because now with my budget ypipe, when I'm sitting in traffic with the AC on, the car vibrates a bit. |
Re: Re: can't adjust idle because of ECU interference.
Originally posted by emax95 What does a auto 98 max idle at when new? like 800-900 right? So your idle is lower then it should be correct? To me it sounds like you have a problem and raising your idle is just going to cover the problem up. If I was you I would clean your throttle body out and then replace your PCV valve. If you allready did this stuff then I don't know, maybe you need new spark plugs or something. PCV valve was changed around 50k ago. I dont remember what my max idled when she was new, but it wasn't 800-900. I dont remember it being that high. I think it was around 650-700. When the AC is on, the idle does go up to around 800. Normally that is good enough, but with aftermarket y, there is a slight vibration, so I was thinking about raising it to around 900. MY gear is in D all this time. Without the AC, the car sits perfectly still at D. Amazing for a car with 120k miles. Procedure I followed to try to raise the idle. 1. Start the car. 2. Put the car in D, have a friend stepping on the brake so the car doesnt run me over! 3. Turn the plastic screw counter clock wise. This seemed to work for a minute, but the idle came back down.. * TPS wasn't disconnected. Does it have to be? |
Re: Re: Re: can't adjust idle because of ECU interference.
Originally posted by hokiemax I've never cleaned my throttle body in 120k miles.:wall: PCV valve was changed around 50k ago. I dont remember what my max idled when she was new, but it wasn't 800-900. I dont remember it being that high. I think it was around 650-700. When the AC is on, the idle does go up to around 800. Normally that is good enough, but with aftermarket y, there is a slight vibration, so I was thinking about raising it to around 900. MY gear is in D all this time. Without the AC, the car sits perfectly still at D. Amazing for a car with 120k miles. Procedure I followed to try to raise the idle. 1. Start the car. 2. Put the car in D, have a friend stepping on the brake so the car doesnt run me over! 3. Turn the plastic screw counter clock wise. This seemed to work for a minute, but the idle came back down.. * TPS wasn't disconnected. Does it have to be? 1. Make sure car is warmed up fully. 2. Disconnect TPS. 3. Start car and rev engine 2-3 times to 2000-3000 rpm. Then let idle stabilize. 4. Adjust idle to speed desired. 5. Stop engine 6. Reconnect TPS 7. Start car and rev as in step 3 8. Is the idle the one that is desired? My guess is that with the TPS connected, you're fighting the ECU when you're trying to adjust the idle, it's trying to go back to what it knew. By disconnecting the TPS, you must be telling the ECU to stay out of it. After the adjustment, and the TPS is reconnected the ECU thinks that this is the idle and will maintain that now. If you use the above procedure, I think you'll have better results. Note: Do not disconnect or connect the TPS with the engine running, it can cause voltage spikes. |
Re: Re: Re: Re: can't adjust idle because of ECU interference.
Originally posted by iwannabmw Try this procedure, it's paraphrased from the one in the book: 1. Make sure car is warmed up fully. 2. Disconnect TPS. 3. Start car and rev engine 2-3 times to 2000-3000 rpm. Then let idle stabilize. 4. Adjust idle to speed desired. 5. Stop engine 6. Reconnect TPS 7. Start car and rev as in step 3 8. Is the idle the one that is desired? My guess is that with the TPS connected, you're fighting the ECU when you're trying to adjust the idle, it's trying to go back to what it knew. By disconnecting the TPS, you must be telling the ECU to stay out of it. After the adjustment, and the TPS is reconnected the ECU thinks that this is the idle and will maintain that now. If you use the above procedure, I think you'll have better results. Note: Do not disconnect or connect the TPS with the engine running, it can cause voltage spikes. |
hokie....
The y pipe should not make your car vibrate.
Did you check that first? Might be a fitment issue with the Y. BTW, how is the kit doing...how many bottles you fill so far? DL |
I have an 02. I raised the idle from 625RPM ro 675RPM with a Consult II. The change seems to have stayed.
Stereodude |
Re: hokie....
Originally posted by dlicari The y pipe should not make your car vibrate. Did you check that first? Might be a fitment issue with the Y. BTW, how is the kit doing...how many bottles you fill so far? DL The kit is doing great!! hahaha. I've gone through one bottle now. And guess what, I upgraded to a 70 shot, and I'm runnin blind!! I"m using a 042 jet for nos, and 032 for the feul Tee. I know the combination stated in the manual for a 70 shot is .036 NOS and .042 fuel Tee, but SR20DEN told me to use .042/.032, so thats what I'm using. But I havent sprayed with these settings yet. Will post again after I do that. |
Re: Re: Re: Re: can't adjust idle because of ECU interference.
Originally posted by iwannabmw Try this procedure, it's paraphrased from the one in the book: 1. Make sure car is warmed up fully. 2. Disconnect TPS. 3. Start car and rev engine 2-3 times to 2000-3000 rpm. Then let idle stabilize. 4. Adjust idle to speed desired. 5. Stop engine 6. Reconnect TPS 7. Start car and rev as in step 3 8. Is the idle the one that is desired? My guess is that with the TPS connected, you're fighting the ECU when you're trying to adjust the idle, it's trying to go back to what it knew. By disconnecting the TPS, you must be telling the ECU to stay out of it. After the adjustment, and the TPS is reconnected the ECU thinks that this is the idle and will maintain that now. If you use the above procedure, I think you'll have better results. Note: Do not disconnect or connect the TPS with the engine running, it can cause voltage spikes. That's exactly what it says to do. IanS |
Re: Re: Re: Re: Re: can't adjust idle because of ECU interference.
Originally posted by iansw You're either VERY good, or quoting from the Chilto's manual. That's exactly what it says to do. IanS "Try this procedure, it's paraphrased from the one in the book: ":) |
Re: Re: Re: Re: Re: Re: can't adjust idle because of ECU interference.
Originally posted by iwannabmw That was pretty much a quote, note the first sentence: "Try this procedure, it's paraphrased from the one in the book: ":) |
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