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1998 Saturn SL1

1998 Saturn SL1 4 cyl

My wifes car is basically stuck at about 55 mph. When in park it idles at about 2800rpm. If I put it in drive it goes down to about 2000rpm and goes about 55mph. I have checked the cable and linkage. It seems to be working properly. I cant hear any obvious vacuum leaks. I was wondering if there is a sensor of some sort that may have gone bad. Any help would be appreciated. Thanks!
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Jdenton83
May 11, 2010.




See if u have any codes and if u do let me know what they are.U should the way that is running. Take off ur intake tube make sure ur throttle plate is closing all the way.I would suspect a vaccuum leak or a stuck idle air control motor. Lets try this to see which one we have. With the intake tube off u will see a opening at the bottom off ur throttle body opening. Block that hole off not with ur finger incase the car back fires thru the throttle body get creative. See if the idle comes down alot if not its getting air somewhere else. Also inspect ur s shaped hose going from ur intake manifold to ur valve cover look for colasping or holes. Let me know what u find.

Saturntech9
May 11, 2010.
I am not sure how to get codes. I am not seeing s shaped hose. When I cover that hole the car cuts off. Thanks.

Tiny
Jdenton83
May 11, 2010.


http://www.2carpros.com/forum/automotive_pictures/416332_1999_sl1_valve_cover_1.jpg



http://www.2carpros.com/forum/automotive_pictures/416332_1999_sl1_iac_1.jpg


if u dont live in california u can get ur codes checked for free from any auto parts store like autozone.u cant find the s shaped hose maybe u have a sl2 and not a sl1 i posted a pic of the sl1 valve cover does urs look like that?if not u have a sl2.so the engine dies when u cover the hole?ok next step then i posted a pic of the throttle body and the idle air control valve its figure 7 i want u to tap on it while the car is idling really high dont hit it hard enough to knock it off of course.just a good tapping see if the idle comes down.and see about getting me some codes if u dont live in california at the auto parts store.let me know what u find.

Saturntech9
May 11, 2010.
I tapped on that with no result but I can get it to idle down by partially covering the small hole by the butterfly. What do you think

Tiny
Jdenton83
May 11, 2010.
It sounds like the idle air control valve is causing the high rpms but we don't know if the motor is frozen up or if carbon is keeping it from closing the proper depth or if we have a wiring issue keeping it from getting power to the motor to move it in and out. If we saw if it had codes or not that would help also.I would try getting a good brand of carb spray and removing that valve and cleaning the plunger tip and that hole u cover to make the idle go down real good and see if that helps. Let me know what u find.

Saturntech9
May 11, 2010.
I got the codes this morning. TPS - P0122. I ordered a throttle position sensor. Now I need a drawing to find out where that is. Thanks again.
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Tiny
Jdenton83
May 12, 2010.
The pic I posted with the throttle body has the tps in it it's figure 6.U can try replace the tps but u could very well have a wire or terminal tightness or some other issue instead. But if u would like to try swaping it that's up too u. Let me know what u find.

Saturntech9
May 12, 2010.
Changed out the TPS. That cleared the check engine light but still did not fix the problem. I cant find any kind of wire issue. I assume that the TPS is eliminated because the alarm cleared. Any more ideas would be appreciated.

Tiny
Jdenton83
May 14, 2010.
Have u tried taking off the idle air control motor like I suggested and cleaning the port and the tip of the motor yet. Let me know.

Saturntech9
May 14, 2010.

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