I have a st165 and when i start it starts reving from 1.5 rpm to 2 and drops again to 1.5 and revs again to 2 and keeps doing this ...i took out the throttle body and cleaned put a new gasket. it does the same thing after again checked all air ways evrthing is fine even put a new air filter and same thing any help?
Okay this may sound stupid but if your telling me that the car idles at 1500 and slowly climbs to 2000 and then drops back down to 1500 and repeats the process of climbing back up to 2000 and then dropping back down over and over then check your coolant level, take off the radiator cap and make sure your radiator is full. I had that same problem on my GTS and thats what my local dealership told me to do and sure enough my rad was low and when I filled it up no more cycling from 1500 up to 2000 and then back down over and over again.
That sounds like the IAC valve to me. The idle I mean, fix that first then worry about the throttle response. What happens when the step on the throttle and bring the engine to a steady say 2500rpm? Do the revs smooth out? I don't know much at all about where the IAC valve and lines are located on a trac, so hopefully some one else can help with that.
how old are the leads and plugs and did you reset your ignition timing? this would be what i would do first before anything this can give you a rough idle and throttle hesisation timing on gte should jump between 12 and 21* at idle warm engine and when u cross the pins for the timing buhind the strut it should be 10* at idle that would fix rough idle but i not sure if it would help one that jumps up and down like yours but check anyway
ok when i press on the gas nothing it just keeps reving up and down but when i take off the tps sensor it revs normally when i press on the gas just harder to start up without it and the timing is good ive reset it im having a feeling its the tps but anyone can tell me for shure its somthing else cuz i dont wanna get a new sensor and then its not the case.
FYI : 3SGE doesn't have an ISC valve only the 3SFE & 3SGTE engines use them. Heres the tests for a 3SGE throttle body. The electrical tests are the same for a 3SGTE throttle body with the exception of the last test ( - VC- E2 3-7k ohms) should be - VC- E2 3-8.3k ohms Ignore the vacuum tests they are different for an All Trac In the chart below the last line ( - VC- E2 3-7k ohms) should be - VC- E2 3-8.3k ohms for an All Trac
I mean this guy. I couldn't find a page with the 3sgte, but once you check the TPS, do the hose pinch on this page. If the air valve is broken, when you pinch the hose the revs should flatten out. Let us know how it works out.
I haven't scanned my ST165 manual yet I'm still working on the ST162 manual. The ST165 manual is just a supplement to the ST162 manual and only contains info specific to the All Trac.
It sounds to me like you are hitting the emissions fuel cut. The fuel cut-off rpm for a 3s-ge is 2000rpm. The fuel return rpm is 1600. This fits with what you are exhibiting. See the manual here: http://www.st165-all-trac.net/st162manu ... /fi110.jpg Basically, whenever the revs are above 2k, and the Idle points are closed on the Throttle Position Sensor (foot not touching the gas pedal), the ECU believes you are coasting downhill. Subsequently, it will cut the fuel for emissions purposes. As you reach the bottom of the hill and the car slows down, the ECU will turn the fuel back on at 1600 rpm. If the idle is set too high you will exhibit a repeating fuel cut and return (cut and return, cut and return...) with the car sitting still. My 87 GT-S does this when it is very cold outside. I can fix it by turning the idle down, but then it is too low after the engine warms up.
me = winner my car stoppeddoing it with a new maf im quite sure... when going down hills in neutral it used to do that but not anymoreeee
Yeah cuz i chaged the throttle body tps and iac valve and still the same thing ... how do you lower your idle?
There is a little rubber plug (green arrow) remove it and there should be an idle speed adjusting screw under it.
I'm going to resurrect a new thread because this one covers all of the issues I am having...Is there any way to have the information posted above be posted again...apparently the website it all came from is closed...
