throttle body

[coreyc123]

ok so i was wonder what sensor is on the throttle in the back by the throttle cable?
/ubbthreads/images/graemlins/jawdrop.gif

 

[SmoothCustomer]

TPS Sensor.

Edit: That's throttle position sensor. It senses how far open/closed the throttle plate is and tries to match it with the proper amount of fuel based on how much air should be coming through that plate.

 

[turbowop]

Or...idle switch or ISC motor. Newbs don't explain things very well so it's hard to tell exactly what he might be talking about.

 

[SmoothCustomer]

Oh, you're right probably the idle switch. I doubt it's the isc though.

 

[prove_it]

Are you asking about the 6 wire thingy or the single wire doohicky?

 

It sounds like you are probably talking about the idle-closed switch. Its just a single wire, right?

 

[prove_it]

Yea single wire, on off switch.

 

[coreyc123]

yeah single wire

 

[prove_it]

Yes that is the closed throttle idle switch. It's important for the ecu to have this input, otherwise you'll have idle issues when coming to a stop.

 

[coreyc123]

ok cool thanks mitsubishi would be the only place i could get it from

 

Are you sure your's is bad? There's really not much with them that can go wrong. Sometimes they get a little oxidized, but can be cleaned up. Oftentimes I have seen them be misadjusted, but someone who thinks they are an idle speed adjustment. The plunger simply gets connected to ground when the throttle opens.

 

[coreyc123]

Well i am like 50% that its bad. I get and idle sureger and i unplug it and the car will start to idle fine after that i wouldnt say im the best with car tho.

 

[prove_it]

Keydiver correct me if I'm wrong but:

The switch is good. If you unplug the switch and it idles better then that means the computer is getting a signal from the switch. All that switch does is send a ground signal to the computer. It doesn't really sense anything. That switch is only for coasting the engine down when you push the clutch in while coming to a stop anyways. Not really used for just idling while motionless. The ISC controls that, and those are common failures.

Go to vfaq.com and read up on idle surge. That will give you more info.

 

[coreyc123]

ok thanks

 

[fivestardsm]

This might help a little.

 

[SmoothCustomer]

It could be so many things that if you have money get a rebuild. Could be just shaft seals...Could be tps...

 

[1990ggsxnj]

The idle surge is actually telling you the idle switch is GOOD. Why? Because too much air (faulty BISS, Leaky FIAV, Incorrect Idle adjustment, incorrectly adjusted CLOSED THROTTLE SWITCH, etc) is getting injested. When this happens, the ecu has two things it can do. 1) Add more fuel to match the air coming in or 2) shut fuel/spark off to drop the revs. If you notice, with the switch unplugged, the idle stabilizes but usually HIGH (correct me if I'm wrong) because it thinks the throttle is open and you want to GO! so with the added air, it just matches with fuel as if you're driving normally. With it connected, it knows that you're not applying throttle. When this happens, you get a condition caused by the ecu itself (idle surge) because it thinks it shouldn't be reving above a certain point (the point where the idle drops during the surge).

This is how I understand it and may help you understand why you need to invest a bit more time in troubleshooting other areas to cure this. VFAQ's are great tools. I personally would start with a boost leak test. It cures many ailments and can save you time later on by preventing what would have been an additional problem.

 

Yes, this is correct. Your Idle Switch is GOOD. What you need to do first is set the idle speed, as per the VFAQ:
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