| Author | Message | ||
     Jim H. (Victor_mature) Member Username: Victor_mature Post Number: 91 Registered: 02-2003 |
My 94 D1 was getting a racing idle after hot starts, I cleaned the stepper motor (very dirty) and the idle was remarkably improved. Then, about a week later, racing idle was back with a vengence. I was stumped so I brought it to the dealer. They told me they "made a stepper motor adjustment using the testbook" and corrected the problem. What type of adjustment can be done to the stepper? Is it a physical adjustment or a "programming" type of issue using the testbook software? I don't want to pay the dealer $200 for fixing the "Thelman wire and the Fetzer valve." Did they actually do anything? (movie buffs will know what that means) -Jim | ||
| Dave Van Haren (Plain2000dii) New Member Username: Plain2000dii Post Number: 26 Registered: 05-2003 |
Actually, Jim they might have only tweaked the flux capacitor. even non-movie buffs will know what that means | ||
| Douglas McMillan (Mcmillan) Member Username: Mcmillan Post Number: 43 Registered: 06-2002 |
I had a problem with the Stepper Motor. The dealer told me they replaced it. However when I had the problem come back they told me that they had only cleaned it. There is no 'adjustment' on the stepper that I know of. | ||
| Rob Davison (Pokerob) Senior Member Username: Pokerob Post Number: 1752 Registered: 02-2002 |
when you relpace it or put it back in you are supposed to wind it to it's minimum height by pushing the spring down and screewing the probe in. after a few days it will adjust itself out and the car will run nicely. usually right afterthe change it runs a little wierd. | ||
| Shaun Power (Shaunp) New Member Username: Shaunp Post Number: 40 Registered: 05-2003 |
Ok guys what the dealer means is that the stepper is out of it's range. This means that it can't control the idle one way or another ie it can't bypass enough air to maintain idle speed. This is corrected by setting the base idle. What you do is block of the air supply to the stepper and adjust the base idle for about 650 rpm, then un block and your a way, this will put the stepper in the middle of it's range. | ||
| Rob Davison (Nosivad_bor) Senior Member Username: Nosivad_bor Post Number: 536 Registered: 02-2003 |
interesting. i wonder how base idle got changed... rd | ||
| Joey (Joey4420) Member Username: Joey4420 Post Number: 66 Registered: 04-2003 |
The stepper motor is contained within the throttle housing and operates a cam and push rod via a reduction gear. The push rod is in direct contact with the throttle lever and moves the throttle disc to control idle and fast idle speed. The stepper motor maximum movement is 3.75 revolutions accomplished in steps of 7.ƒ¥¢X. The reduction gear converts this into 18ƒ~¢Xof cam movement. The throttle lever has a throttle position setting screw which rests on the stepper motor operating pin when the throttle pedal is released and is used to set the relationship between engine speed and stepper motor position. In the side of the throttle housing is a throttle air bypass bleed screw to provide easier and more sensitive setting of the stepper motor position at idle. The stepper motor position is checked using Testbook and should be within the range of 20 to 40 steps when the engine is run in. If it is identified as being outside this range it can be adjusted to within range by turning the throttle air bypass bleed screw. It is important to follow Testbook setting procedure when adjusting this screw to prevent mismatching of throttle body settings. This ensures that the stepper motor is at the optimum position within its range for providing further movement to compensate for changes in engine load or temperature in accordance with signals from the ECM NOTE: The stepper motor and throttle position setting screws must only be adjusted when Testbook identifies the requirement. | ||
| Jim H. (Victor_mature) Member Username: Victor_mature Post Number: 92 Registered: 02-2003 |
Ow. Joey, you made my head hurt. So is removing and cleaning the stepper a procedure that should be left to the dealer (or those who have testbooks)? -Jim | ||
| Joey (Joey4420) Member Username: Joey4420 Post Number: 68 Registered: 04-2003 |
Jim, sorry I didn't mean to make you head hurt... all the above data was pulled out of the Rave CD manual (at least the part that I have) Downloaded a portion of the Rave CD, just can't find the link anymore. |
