Hesitation while driving non electrical
04-13-2010, 11:24 PM
#1
Cruisin'
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Hesitation while driving non electrical
??? I have and 84 944 that i cannot figure out a small hesitation while driving. I have installed a wide band 02 sensor with and air/ fuel gauge. While I am cruising down the road with the pedal partially down and the car running fine it will all of a sudden have a hesitation and slow. It will then pick right back up and go like nothing is wrong. I took a look at my air/fuel gauge when this happened and it shows that it goes full lean even when the pedal is down. It also jumps right back to its original reading when the car gets going again. It does not seem to happen on acceleration just while driving. Any ideas?
04-15-2010, 07:51 PM
#3
Cruisin'
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I tried this last night as well as cleaning the entire afm from the directions on clarks garage and drove the car today it seems to be running much better. I do however need some clarification on the allen screw adjustment that is on the afm. i was told it was for air fuel mixture. I have been adjusting it to what I have been told to make a richer mixture for the track. When I have done this after cleaning I noticed that the car does not run as well and it has stalled on me when I have been coming to a stop. It was a trial and error procedure to figure this out. Is there a certain way to figure out the correct adjustment, or am I doing something wrong. Another note on my air fuel wide band gauge it has told me that I have a richer mixture with the allen screw tightened more.
04-15-2010, 10:34 PM
#6
04-16-2010, 04:45 AM
#7
Burning Brakes
I don't understand why you'd want to screw around with the mixture setting when you have no guide or test equipment and clearly little knowledge or experience ?
The ECU is constantly making fine adjustments to the fuel/air mixture based on the info it receives . Any alteration of any input/ sensor settings is going to throw it out.
What exactly were you trying to achieve ?
If I were you i'd return it to stock and see if everything returns to normal.
The ECU is constantly making fine adjustments to the fuel/air mixture based on the info it receives . Any alteration of any input/ sensor settings is going to throw it out.
What exactly were you trying to achieve ?
If I were you i'd return it to stock and see if everything returns to normal.
Last edited by peanut; 04-17-2010 at 12:08 PM.
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04-16-2010, 09:46 PM
#8
Cruisin'
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Please do not judge knowledge and experience on a simple question. I have had some issues with this setting in the past due to the cars condition when I received it. I was told by someone else with plenty of experience what the adjustment is supposed to be doing. Since I am not achieving what I was told it would do, I thought that I would be able to ask and get a correct answer. Did you ever stop to think that the Adjustment was incorrect or not working properly?
04-17-2010, 05:58 AM
#9
Burning Brakes
Please do not judge knowledge and experience on a simple question. I have had some issues with this setting in the past due to the cars condition when I received it. I was told by someone else with plenty of experience what the adjustment is supposed to be doing. Since I am not achieving what I was told it would do, I thought that I would be able to ask and get a correct answer. Did you ever stop to think that the Adjustment was incorrect or not working properly?
Well I would suggest that you get your original advisor to sort the problem seeing as he has 'plenty of experience'
I wish you luck
04-17-2010, 12:12 PM
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As others said (some not so eloquently), return the mixture screw to the stock setting. Everytime you move it the computer makes adjustments to compensate for the new mixture it is seeing and trys to put things back to the stock settings. Check and clean all connections to the AFM, TPS (thottle position sensor, sits under the throttle cable cam).
I had a similar problem a few years ago. It started out as very intermittent and then transformed into a disabled car. If it was in my driveway, no problem. Unfortunately it happened on the first day of 3 day DE at Mt Tremblant. To make a long, expensive story short, the problem turned out to be the TPS. We didn't look at it in the beginning because I replaced that &^*@! piece a few months earlier.
As a test you can unplug the TPS and run the car. It will run rich, but if the symptom goes away that is your problem. There is an ohm test; however, in my situation the TPS passed that test, yet was still the culprit.
I had a similar problem a few years ago. It started out as very intermittent and then transformed into a disabled car. If it was in my driveway, no problem. Unfortunately it happened on the first day of 3 day DE at Mt Tremblant. To make a long, expensive story short, the problem turned out to be the TPS. We didn't look at it in the beginning because I replaced that &^*@! piece a few months earlier.
As a test you can unplug the TPS and run the car. It will run rich, but if the symptom goes away that is your problem. There is an ohm test; however, in my situation the TPS passed that test, yet was still the culprit.
