I've been using the search, archives, factory manual for the entire afternoon and the more I read, I think the more I am getting lost, (I think)... Everyone's situation seems to be different in each thread I searched / read whether it be aftermarket computers, no emissions, etc, etc... So Ive decided to make my own thread.

Here's the story on my situation. The car is a 1987 TII. The previous owner removed the air pump so now there are some plugs hanging and tubes uncapped. The car has a 3" straight threw exhaust w Magna Flow mufflers, HKS FCD, and I *think* a S5 motor.

When I start up the car cold it doesn't kick up to hold a higher idle like I think it should. Instead it acts like a carb'ed car where I have to play the pedal until it warms up and then she'll stay running on her own. The idle will drop down to 800ish for a second or two and then it kicks up to 1500ish and stays there.

I'm a body guy, so sorry for being such a noob in the mechanic dept. Thank you in advance for any help.

 

So after flipping threw the factory manual I've learned that the ECU takes a reading of engine load off the clutch pedal switch (which is jumped out atm) and from the neutral switch (which could possibly be unhooked). During the clutch swap I knocked a wire clean off a switch top o' the trans... I figured it was the reverse lights no biggie at the time... Looks like I'm going to have to further investigate. Ohhhh please let it be this simple.

 

If the ECU thinks the clutch has been depressed then it won't initiate the 3000 rpm startup.

 

So wait a second, I have to press the clutch to get the starter to crank...? How do I get the car to start without pressing the clutch...?? I don't think it cranks when in neutral...???

 

If you have the Interlock Switch then you need to depress the clutch pedal. If you don't have the switch then you don't need to bother w/the pedal.

 

So after searching "interlock" I definatly have one.

I'm kind of confused tho...? I get no 3k rpm start up bc of this switch...?? The car runs GREAT once she warms up.

 

The 3K startup is not related to the Interlock Switch but is related to the Neutral Switch. Also, the 3K startup is directly related to the temp of the coolant upon a cold start. If the temp of the coolant is below 62 degrees then there will be no 3K startup and if the temp of the coolant is above 62 degrees then there will. There is a temp switch at the bottom of the radiator which tells the ECU what the temp of the coolant is and it only has two positions either above 62 or below 62. When above 62 the ECU receives a ground signal at pin 1H. If 1H receives a ground upon a cold start then the car should start w/the 3K startup, "but" it will be overidden if the ECU thinks the car is not in neutral. Pin 1G of the ECU is for the Neutral Switch. When in neutral the pin receives less than 1.5 volts and 12 volts when in gear. If the pin receives 12 volts then the car will not rev up to 3K upon a cold start regardless of the coolant temperature.

 

Thanks again Satch. I didn't get under the car and investigate the temp switch on the bottom of the radiator yet but I did find out that the sensor on the back of the water pump was unplugged, why I have no idea....?? But after plugging it back in the car starts beautifully and cold starts. Idle doesn't drop below 1200 when warm yet tho. I'm getting there.

Just a quick pic of what I have to go threw just to get a jack under the front end. I love the way the car sits and rides.... Not very practical tho.



Reminder to self.... Check neutral switch @ transmission.

 

Could be the throttle cable is to tight. Could be the Fast Idle Cam is not set properly or working correctly. Could be misadjusted primary plates. Could be a small vacuum leak. Or a stuck BAC are some possibilities.

 

I built a stack of 2x6 boards 3 high, angled and stagerd the ends. I just leave in the garage and park on every night. Works great

 

Just disconnect the cable altogether.
The car doesn't need the pedal to start or idle.