Surging idle and cold start problem fixed. Long winded, but good moral at the end!
10-25-2004, 06:23 PM
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Surging idle and cold start problem fixed. Long winded, but good moral at the end!
(If you're not in the mood to read this, scroll to the bottom and see the moral...)
SURGING IDLE:
I initially thought my surging idle was due to a bad ISV. I pulled it and shipped it to AudiSport4000 in Indy, who ever-so-nicely put it in his and confirmed that it was fine. So I thought my culprit was the idle switch at the bottom of the throttle body. I got a throttle body and switch from Team Audi Trippin ready to install.
This weekend, I took my car home to my Dad for some TLC. We ended up putting hose clamps on every outlet of the little rubber thingy that holds the ISV to make sure there were absolutely no vacuum leaks. Some of these outlets never had clamps, so we were hoping this would make a difference.
Believe it or not, it sure did! She's idling perfectly at 1000 now and not surging. I still plan on putting in the throttle body, as mine is sort of sticky at the secondary butterfly.
COLD START:
Petunia (that's my 4kq, shut up...no cracks!) just started not turning over on the first try. The second she would, but would feel flooded and would stall if I didn't gas it. This is sort of funny because this is the exact same problem that she had when I got her in 1996. What's even funnier is that I posted the solution on this forum <a href="https://forums.audiworld.com/4000/msgs/47952.phtml">here</a> explaining what happens if no love was coming from the cold start switch. So why didn't I think to check this out for myself? Who knows. Oops!
Turns out that the 2 wires coming from the starter were virtually disintegrated. In particular, the wire from the starter to the cold start switch was actually not connected any longer. This would explain my starting problem! Here is a pic of the "good" ignition wire:
<img src="http://www.audi4000.com/albums/Starter/IMG_3134.sized.jpg">
In removing the white plug that goes to the starter, good ole Dad snapped off the "L" connector on the starter. This basically forced me to get a new starter. (I grew up in the sticks and twigs, so there's no import places or even a big auto parts place. We called Advance Auto at noon on Saturday and had the starter by 11:30am Sunday for $97, cheaper than any online Audi supplier!)
<img src="http://www.audi4000.com/albums/Starter/IMG_3143.sized.jpg">
<img src="http://www.audi4000.com/albums/Starter/IMG_3145.sized.jpg">
So on Sunday, Dad and Scott got the new starter in and rewired everything. Now she starts up immediately on the first rev.
Also, in taking off the wheel to get to the starter, Dad pointed out that the rust build up on the back of my rotor had worn NASTY grooves in my brake pads. Hmm...guess this could explain my sluggish braking as of late? So, I just ordered the front brake rotor and pad kit from Blau today (using Scott's $64 credit he had there, so it was basically 50% off for me with that! Whoo!) and this will be a good weekend project for me and Scott.
MORAL OF THE STORY:
Long-winded, but if you're having cold start problems...please get under there and take a look at the wires going to your starter! Chances are, they could be as nasty as mine were...and may not even be connected like mine!!
--morgan
SURGING IDLE:
I initially thought my surging idle was due to a bad ISV. I pulled it and shipped it to AudiSport4000 in Indy, who ever-so-nicely put it in his and confirmed that it was fine. So I thought my culprit was the idle switch at the bottom of the throttle body. I got a throttle body and switch from Team Audi Trippin ready to install.
This weekend, I took my car home to my Dad for some TLC. We ended up putting hose clamps on every outlet of the little rubber thingy that holds the ISV to make sure there were absolutely no vacuum leaks. Some of these outlets never had clamps, so we were hoping this would make a difference.
Believe it or not, it sure did! She's idling perfectly at 1000 now and not surging. I still plan on putting in the throttle body, as mine is sort of sticky at the secondary butterfly.
COLD START:
Petunia (that's my 4kq, shut up...no cracks!) just started not turning over on the first try. The second she would, but would feel flooded and would stall if I didn't gas it. This is sort of funny because this is the exact same problem that she had when I got her in 1996. What's even funnier is that I posted the solution on this forum <a href="https://forums.audiworld.com/4000/msgs/47952.phtml">here</a> explaining what happens if no love was coming from the cold start switch. So why didn't I think to check this out for myself? Who knows. Oops!
Turns out that the 2 wires coming from the starter were virtually disintegrated. In particular, the wire from the starter to the cold start switch was actually not connected any longer. This would explain my starting problem! Here is a pic of the "good" ignition wire:
<img src="http://www.audi4000.com/albums/Starter/IMG_3134.sized.jpg">
In removing the white plug that goes to the starter, good ole Dad snapped off the "L" connector on the starter. This basically forced me to get a new starter. (I grew up in the sticks and twigs, so there's no import places or even a big auto parts place. We called Advance Auto at noon on Saturday and had the starter by 11:30am Sunday for $97, cheaper than any online Audi supplier!)
<img src="http://www.audi4000.com/albums/Starter/IMG_3143.sized.jpg">
<img src="http://www.audi4000.com/albums/Starter/IMG_3145.sized.jpg">
So on Sunday, Dad and Scott got the new starter in and rewired everything. Now she starts up immediately on the first rev.
Also, in taking off the wheel to get to the starter, Dad pointed out that the rust build up on the back of my rotor had worn NASTY grooves in my brake pads. Hmm...guess this could explain my sluggish braking as of late? So, I just ordered the front brake rotor and pad kit from Blau today (using Scott's $64 credit he had there, so it was basically 50% off for me with that! Whoo!) and this will be a good weekend project for me and Scott.
MORAL OF THE STORY:
Long-winded, but if you're having cold start problems...please get under there and take a look at the wires going to your starter! Chances are, they could be as nasty as mine were...and may not even be connected like mine!!
--morgan
10-26-2004, 09:35 AM
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I would have killed for the info regarding the idle on my last 4KQ!
The idle on my prior 86 4KQ was erratic from the day I bought it until the day I sold it. It drove me nuts.
I adjusted the air/gas mixture and replaced the vacuum hoses. I replaced the temp. sender for the ECU. In addition, I replaced the fuel pump/filters along with the typical tune-up items (rotor cap. button, plugs wires & wires etc.). The ISV was cleaned like a SOB. None of this had any effect on the idle.
I would have never thought to put clamps on the connectors to the ISV (considering there were never any to begin with).
Kudos to you and your Dad!
I adjusted the air/gas mixture and replaced the vacuum hoses. I replaced the temp. sender for the ECU. In addition, I replaced the fuel pump/filters along with the typical tune-up items (rotor cap. button, plugs wires & wires etc.). The ISV was cleaned like a SOB. None of this had any effect on the idle.
I would have never thought to put clamps on the connectors to the ISV (considering there were never any to begin with).
Kudos to you and your Dad!
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