Erratic Idle- Van idles very high like throttle floored
So The van will first idle normal , then low like almost shuts off, give it some gas and it back to normal. But after running it for awhile the idle races. for example at a stop light it sounds like Im trying to power brake the beast. I changed teh idle air valve and no change, ANY SUGGESTIONS ARE welcomed
That's a tough one not being there an knowing the year of the van too.
That high of idle is really uncommon. You may have one or several issues. Super high idle can be caused from a vacuum leak, or a misreading sensor. It could be that your TPS is reading a full 100% after it warms up. I have had two temp sensor issues (trans and air intake temp) like that on my van before that caused weird issues. The coolant temp sensor has a lot to do with idle, but I am unsure if it would cause such an anomaly. I know the air intake temperature sensor has a lot to do with timing, so that probably isn't it. For that high of idle, you have to have the air source to support it. So...something is giving it air or something is causing the air...
You can get a OBD II scanner that is Bluetooth off of ebay or Amazon. Then you can use the Toque app to look at the sensor readings. In the fully version of Torque you can log the data from the sensor. When your idle goes high is when you want to analyze that data with the previous data when cold. A large variance or non-linear reading from a sensor usually points to the issue. You get to this point of diagnosis after you rule out the basics like vacuum leaks, bound up cables, leaky injectors etc.
Post more of your thoughts and may be we can fix it..
That high of idle is really uncommon. You may have one or several issues. Super high idle can be caused from a vacuum leak, or a misreading sensor. It could be that your TPS is reading a full 100% after it warms up. I have had two temp sensor issues (trans and air intake temp) like that on my van before that caused weird issues. The coolant temp sensor has a lot to do with idle, but I am unsure if it would cause such an anomaly. I know the air intake temperature sensor has a lot to do with timing, so that probably isn't it. For that high of idle, you have to have the air source to support it. So...something is giving it air or something is causing the air...
You can get a OBD II scanner that is Bluetooth off of ebay or Amazon. Then you can use the Toque app to look at the sensor readings. In the fully version of Torque you can log the data from the sensor. When your idle goes high is when you want to analyze that data with the previous data when cold. A large variance or non-linear reading from a sensor usually points to the issue. You get to this point of diagnosis after you rule out the basics like vacuum leaks, bound up cables, leaky injectors etc.
Post more of your thoughts and may be we can fix it..
Sorry Guys, Its a 99' 3500 Ram van. I did not clean the throttle body or reset the PCM. I do however now have no brakes when its running. Was thinking that was a bad brake booster but now that you say vacuum issue they could be related right? I have OBD II and will try your suggestion tomorrow.
Last edited by 3500 Ram Van; Oct 15, 2019 at 09:09 PM.
So checked this morning and the vacuum hose is connected and intact. However the brake reservoir was empty again and I filled it up pumped the brakes and checked all for corners for fluid. Noticed fluid under the center of the van near the transmission. As I ran the van I noticed it started to smoke and as i pumped teh brakes the smoke got more intense. I would say I have a leak that is hitting something hot . Now just have to trace down brake lines










