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Discussion Starter · #1 ·
I have a 01 zx3 automatic...starts,runs & idles fine with no CEL's on. When i de-accelerate off like a exit ramp or something then hit the brakes it just dies but also dies by just hitting the brakes (not everytime) .Sometimes it will stumble like u bump start a stick shift & restart (or not totally dies) but most times it just dies.It idles perfect & gas milage & drivability are normal just dies sometimes when braking very hard. I notice it dies usually by having no power stearing & the red engine light on the dash as its pretty random when it happens.i just bump it in neutral & hit the key & it starts right back up & drives away fine its weird.slow speeds around town i usualy dont have any issues.

If i am itleing in park & rev it up real fast above 5k rpms & let off it will die but always starts right back up. i have no throtle hang up issues & the car is totally stock with around 83k on it.

I was told its probably the TPS sensor but would like to know before i spend $130 on a new throtle body & sensor (have to replace both on a stock TB with an auto i hear). any other opinions on what my problem might be?
 

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Does it idle fine right after you fire it on a cold startup? My car did a similar thing with stalling after braking and I found out it was the IAC.
 

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As far as I know you wouldn't have to replace the throttle body along with the TPS sensor. The TPS sensor has two screws on the side of the TB, just undo those screws and replace it with a new one is all I have done in the past. First time I have heard that you would have to replace the TB along with the TPS. The only thing difference between an automatic and manual TB is the mounting plate for the throttle and cruise control cable.
 

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Your IAC (idel air control) is bad. It is on the inside curve of the intake manifold and you have to take the manifold off to replace it. The reason your car is dying when you hit the brakes is because the ABS (which I'm assuming you have) kicks on during a hard brake and takes more power from the engine. When power is taken from the engine the IAC makes the car idle higher and keeps the engine from dying.

The TPS (throttle postion sensor) more than likely is fine. But here's the deal on replacing it if you ever need to. You can not buy them alone for the auto tranny cars but you can for manuals. However you can replace it. Just go to the junk yard and pick one up.

I'm willing to bet good money on the TPS not being the issue. I got a new motorcraft IAC from Steve at Toulsey for $110. For the amount of work to replace it, I would never put a china made part in there.
 

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Discussion Starter · #7 ·
ok cool guys thanks for the info & ill check out the IAC this weekend. I read on another post that the guy removed it & cleaned it with parts cleaner & reinstalled it & it worked fine.I dont have a problem with buyingthe new one if i know for sure thats the problem.

Yes i was told for the Auto trans the factory TB has to be replaces with the TPS but after thats been done then after that u can buy & replace just the TPS.

ANDREW.....mine starts & idles fine all the time.
 

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I can't remember the year cutoff, but the early Foci do have to have the whole TB replaced in order to replace the TPS. If you run up to the point where you think that is your problem, then check Rock Auto and be sure to use our 5% discount from the Rock Auto thread in the Vendor Deals, Group Buys, and Special Discounts forum.

As far as replacing the IAC, you should be able to clean it with carb cleaner, Q-tips, and a rag. You can work the plunger with a Q-tip. If that is your problem, then it's sticking closed.

Didn't you mention a PCV hose split? Fix that too. It tends to lower idle. I read so many threads. That should always be checked with idle problems. Ford makes a replacement PCV line that comes with insulation on the rubber portions to prevent decreased lifespan. IMO, you can build one with plastic 90s and rubber line that will likely last as long as the OEM did- if not longer.
 
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