MP Throttle Body Problems. High idle?

shneeko · Post by **shneeko** » Thu Nov 23, 2006 3:23 pm

Well ive had this throttle for about 6 months now and it has always idled pretty high. sometimes as high as 1.5k rpm. It didnt really bother me as it only did this while in park and neutral. But now im getting CEL (P0507 Too high of an idle rev) and now i need to get this fixed before it gets inspected.

I tried to adjust the idle screw but that still doesnt do anything. One thing ive noticed is that when i first start the car up in park the idle is about 800, which is fine. But if i rev the engine, the needle goes up and slowly comes down and stops around 1.5k.
Now i just went outside to do it once more to try and fix it and i noticed something else as well. If i rev the engine in park and let it go up and settle back to around 1.5 and pop the hood and close the plated manually, it goes back to 800. So it seems like for some reason that the spring isnt strong enough to close the plate so that it rests back on the screw which would bring the idle down. When i closed the plate all the way manually back to the screw, there was about only 1/16 of an inch of gap between the plate and the screw.

However, when i turn the car off and play with the plate. It doesnt stick and it closes very easily by itself.

Anyone got any ideas?

Marthby · Post by **Marthby** » Thu Nov 23, 2006 6:47 pm

Try resetting the PCM by disconnecting your negative battery terminal for like 45 minutes.

phenomeneon21 · Post by **phenomeneon21** » Thu Nov 23, 2006 7:44 pm

You might just need a new Throttle Position Sensor. I remember on my 95 Neon, I thought the throttle was sticking, causing my RPM's to float real high, so I also tried the idle screw and it didn't do anything so I went ahead and replaced the TPS and it fixed my problem right away...they aren't real expensive from what I remember, and it was pretty easy to replace.

shneeko · Post by **shneeko** » Thu Nov 23, 2006 9:12 pm

any idea where i could get one?

kc2005ptgt · Post by **kc2005ptgt** » Thu Nov 23, 2006 9:14 pm

mod-perf probably - junk yard is another place. I have a tb for sale which has all the stuff you need.

$40 shipped.

Post by **Diablo0** » Thu Nov 23, 2006 9:57 pm

If you were to while the car is on, open the plate with your hand does then let it close by itself does it still do it? If it does, disconnect the throttle cable and do it again, does it still do it? There may be some binding on tension in the throttle cable not letting it close all the way or maybe your pedal is sticking somehow. Up until you said closing the TB plate manually I was thinking it was your IAC not functioning correctly and letting too much air through but with you saying when you move the plate closed manually it goes down that shot that idea. Also... the screw on the side is only meant to adjust the plate so that it doesn't stick closed when it shuts, isn't meant to be used as an idle adjustment.

JRM · Post by **JRM** » Thu Nov 23, 2006 10:31 pm

double check the vacuum lines

shneeko · Post by **shneeko** » Thu Nov 23, 2006 10:38 pm

Ill doube check the vacuum lines.

But yea, diablo, when i open the throttle and let it close by itself again, it does settle back to the position to where it sticks and continues to idle high untill i nudge it closed a little bit. I did try and see if there was anything that was putting tension on the throttle cable but everything checks out. Ill try to just uninstall and reinstall it and see if that works. Sometimes its better to just start over again.

Post by **Diablo0** » Thu Nov 23, 2006 10:41 pm

Also, it may or may not help but it might be worth it to put a few drops of oil on... could be like a squeaky door hinge but that seems unlikely.

shneeko · Post by **shneeko** » Thu Nov 23, 2006 10:43 pm

Yea. I was thinking that. But its just too wierd that it closes normally without any problems when the car is turned off. It only sticks when its running. It would make sense if it were a vacuum leak i assume.

dblsg · Post by **dblsg** » Fri Nov 24, 2006 4:21 am

^ mine was idleing high because of a vacuum leak... and it was at about 1.5 k. thats where i would start to look.