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Discussion Starter · #1 ·
My 2000 GT has started acting fishy at the first startup of every day. Problem is that it misses, farts and struggles for about 10 seconds after startup. This only happens when it has been sitting overnight, and never if i drove it already that day. Upon startup the RPMs jump to 2 grand like normal then fall to about 5-600 and struggle unless i give it a little gas, then it will even out to the 8-900 it should be at after about 10 seconds.

This is not a big issue but very annoying because i want everything to be perfect with this car.

Here is what i have done recently.

New IAC valve a couple moths ago
Throttle Position sensor about the same time
Fuel pump about a year ago
Fuel regulator at same time

My theory is that the IAC valve is crappy(BWD brand) from advance auto which i had to switch out a couple times to get running right in first place cuz the first 2 were defective.
1. I think maybe it sticks first startup of the day.
2. Failing oxygen sensors
3. Fuel pump is not pushing good, clogged filter or maybe dirty sock on the pump.
4. maybe a MAF sensor issue somehow

Any experience with this, what are your opinions.

I will double check if there are any codes, today was a cold morning and it stalled on startup for the first time. hopefully it threw a code over this issue.
 

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how are your plugs?
 

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Discussion Starter · #4 ·
Well i went to check for codes at autozone... Found none

I am convinced it is the crappy IAC valve
I told the guy at autozone what im attacking and he told me a similar story with his friends mustang.

I always though in the back of my head since this started that it is the IAC valve sticking at first start of the day.

When someone says buy something at the dealership because its a very crucial piece, one should listen.

Always wanted that piece to be the origional one anyways...
It might be a while but when i do get the ford IAC i will post my results on here
 

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Hm, it may be the IAC valve but sounds fishy. The MAF might be the problem, what happens if you leave your key on for about 5-10 seconds before firing the car?
 

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Discussion Starter · #6 ·
Hm, it may be the IAC valve but sounds fishy. The MAF might be the problem, what happens if you leave your key on for about 5-10 seconds before firing the car?
Tried leaving key on and also tried turning it to second position a few times (different days) and it did nothing different.

Thing i noticed: Struggles way more when its really cold outside at the first startup of the day.
 

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I am having the same issue when its really cold mine also does this. But what I observed was that the car did not do this until I switched my plug gap from .037 to .028... so you might want to check your plugs/wires...

Sent from my XT907 using AutoGuide.Com Free App
 
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