Post Reply 
 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Help.. Question
Author Message
Bassman Offline
Member
***

Posts: 10
Joined: Nov 2008
Reputation: 0
Post: #1
Help.. Question
I have a 2008 Chevy Avon with a small cell and a PWM. I recently installed an EFIE on my Oxygen sensor. After driving on the road without any problems for over an hour, I stopped at a store. When restarted, I got down the road about 3 miles and the car suddenly wouldn't run. It would idle but wouldn't accelerate. I didn't get a check engine light but I opened the hood and took a look. Everything looked normal so I started it up and took off again only to get less then a mile and it did it again but this time I got a check engine light. The computer went into open loop.
I opened the hood and loosened the B+ lug on the EFIE and pulled the wire out to shut it down with the car still running. As the wire came out it was sparking to ground like it was a spark plug wire. Jumping a gap over a half an inch with 3 to 5 sparks a second.
This let me clear the check engine light and I resumed my trip with no other problems.
My question is what caused the sparking? Could it be caused by the frequency that the PWM puts out in conjunction with the cell acting like a huge capacitor? Do you think that it destroyed the EFIE? Has anyone else had this occur?
11-17-2008 02:41 PM
Find all posts by this user Quote this message in a reply
colchiro Offline
Moderator
*****

Posts: 3,265
Joined: Feb 2008
Reputation: 11
Post: #2
RE: Help.. Question
Your efie doesn't connect to your cell so it shouldn't have anything to do with that or the PWM, unless the wire you pulled off was one with the efie and pwm connected. The efie uses so little current, I doubt it would cause the sparking you describe. OTOH, a wire connected to +12v that touched ground would cause a lot of sparks.

You can return the efie to Mike for testing or repair without a RMA and include a printout of this page.

OTOH, it's a simple process to test it yourself. Simply power up your efie after disconnecting and insulating the green and white wires (and brown and blue in the case of a double efie). Now check the offset of your efie like you normally do. If turning the pot still gives you a changing voltage, your efie is good. If you don't get this behavior, box it up and send it in.

Rick

Links: Documents / Tuning for Mileage | Toyota Sensors | Autoshop Sensor Tutorials
11-17-2008 04:20 PM
Find all posts by this user Quote this message in a reply
Bassman Offline
Member
***

Posts: 10
Joined: Nov 2008
Reputation: 0
Post: #3
RE: Help.. Question
colchiro Wrote:Your efie doesn't connect to your cell so it shouldn't have anything to do with that or the PWM, unless the wire you pulled off was one with the efie and pwm connected. The efie uses so little current, I doubt it would cause the sparking you describe. OTOH, a wire connected to +12v that touched ground would cause a lot of sparks.

You can return the efie to Mike for testing or repair without a RMA and include a printout of this page.

OTOH, it's a simple process to test it yourself. Simply power up your efie after disconnecting and insulating the green and white wires (and brown and blue in the case of a double efie). Now check the offset of your efie like you normally do. If turning the pot still gives you a changing voltage, your efie is good. If you don't get this behavior, box it up and send it in.

The wire that I pulled is the same B+ that is common to the B+ feeding the cell but the B- to the EFIE hooks directly to the battery B-. The arc that I was getting didn't affect the 20 amp fuse and was arcing futher then 12 volts would. I don't believe that the EFIE was damaged but I haven't checked it out yet. I also don't believe that it was any fault of the EFIE because the wire was arcing after I pulled it off of the EFIE and it didn't have any connection with the EFIE at that time. I believe that it would have more to do with the PWM as it was the same wire that also feeds the B+ to it and the cell.
11-17-2008 04:32 PM
Find all posts by this user Quote this message in a reply
colchiro Offline
Moderator
*****

Posts: 3,265
Joined: Feb 2008
Reputation: 11
Post: #4
RE: Help.. Question
Ok, now I see what you mean by stored charge in the cell.

Rick

Links: Documents / Tuning for Mileage | Toyota Sensors | Autoshop Sensor Tutorials
11-17-2008 06:09 PM
Find all posts by this user Quote this message in a reply
Gary Offline
Member
***

Posts: 1,542
Joined: Jun 2008
Reputation: 4
Post: #5
RE: Help.. Question
They ARE temporary *(as in leaky, no pun intended) capacitors. But I don't see how a capacitive discharge could repeat unless it was being refed and shorted down repetitively.
(This post was last modified: 11-17-2008 06:56 PM by Gary.)
11-17-2008 06:55 PM
Find all posts by this user Quote this message in a reply
Bassman Offline
Member
***

Posts: 10
Joined: Nov 2008
Reputation: 0
Post: #6
RE: Help.. Question
Gary Wrote:They ARE temporary *(as in leaky, no pun intended) capacitors. But I don't see how a capacitive discharge could repeat unless it was being refed and shorted down repetitively.

It might have something to do with the frequency that the PWM is set at. My oscilloscope isn't working so I can't tell what it's set at. My biggest concern is that it might effect the car's computer. Since the EFIE is a link to it, I'm afraid to hook it back up till I can figure out what caused it..
11-19-2008 07:07 AM
Find all posts by this user Quote this message in a reply
Post Reply 


Forum Jump:


User(s) browsing this thread: 1 Guest(s)