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Weak throttle response...slight surging

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Old 05-06-2005, 06:13 PM
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KAmey1970
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Default Weak throttle response...slight surging

I have an 83 US with AT that has a new TB/WP with the guidance of this forum.

Let me describe my problem and ask for help and advice.

When I hit the gas from a dead stop, I am getting little/no power for the first second or two. I self timed myself on a backroad 0-60 at 10 sec.

When cruising highway speeds everything seems fine though there is a slight surging in the engine that is barely noticible by the passenger, but I feel it.

I replaced the fuel filter and air filter, thinking they may be clogged. I also adjusted the idle slightly higher. I was revving at 250 in drive at dead stop. After the air filter was replaced I thought the problem was slightly worse (or maybe not? hard to tell)

I took out the air filter and noticed the "gate" for use of a better term is wide open at all times when the engine is running.
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I have read the forum rather religiously since getting the shark 2 months ago. I am thinking the next step is a new O2 sensor. Then maybe a AFM (reading the forum I know I don't have a MAF)

Is this the right way to go?

What can a guy with a craftsman set of wrenches do?
Old 05-06-2005, 09:32 PM
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jsherid1
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Is there any chance you have a transmission issue or does the tach just crawl upwards? I am not too familiar with the 16v engines but two other issues spring to mind from my experience with an Audi of similar vintage (apples and oranges) the O2 sensor is one and the catalytic converter is another if it is plugged.
Old 05-06-2005, 10:40 PM
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Big Dave
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Have you checked that the throttle is opening up all the way? You may need to check the throttle cable to make sure it isn't too loose. If it is, you might not be opening the throttle all the way even with the gas pedal pushed to the floor. Have someone (with the engine off) floor the gas pedal while you check to see if the throttle can be opened further by hand (by pulling the cable harder).
Old 05-06-2005, 11:24 PM
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Daniel Dudley
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Are you saying that the air flow meter flap is open all the time? Even when the motor is not running?
Old 05-07-2005, 08:51 AM
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KAmey1970
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The flap opens 100% as soon as the engine starts.

I am admittedly not a "car guy," but I thought the flap gives as much air as needed depending on throttle. I thought being open 100% even on idle was giving too much air.

Am I wrong?
Old 05-07-2005, 02:54 PM
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SharkSkin
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If you're talking about the device in the attached pic... and the "gate" is in the position shown at idle... there is definitely something wrong with it. What that's doing is indicating max airflow to the brain. Maybe the internal spring is broken.... are you getting lots of black smoke out the back?
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Old 05-07-2005, 04:15 PM
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KAmey1970
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The flap I am referring to is right under the air filter. (sorry mother in law borrowed my digital camera) When the engine is running at idle it is completely open.

I did adjust the throttle cable....thanks for that advice big Dave. The hesitation did seem to improve. I didn't do a 0-60 time yet. I noticed that I didn't get "back pushed into the seat" power until about 60 mph.


I almost wish I could drive someone else's 16v to see if I am asking for too much out of my car.
Old 05-18-2005, 10:25 PM
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Giovanni
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Hmmm, so what is wrong with this picture? Isn't the throttle mechanism suppose to be straight? Maybe this is the reason my '88 takes a long time to get to 120 and 1st gear shifts at 4500 rpm.
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