home register FAQ memberlist calendar

Go Back   Turbobricks Forums > Mechanical > maintenance & nonperformance

Thread Tools Display Modes
Old 02-09-2019, 10:14 AM   #1
Brotkasten's Avatar
Join Date: Aug 2017
Location: Wolfsburg, Germany
Default Bosch 2x2 Coil measures dead short

Wanted to make this problem searchable with this thread. Maybe its not a problem at all... I dont just want to order a new coil...

Originally Posted by Brotkasten View Post
I did some more testing today (I ordered Butchka's board and replaced BTI's - LC reasons..) and noticed:

- The car still will start and run really choppy
- Revving up just kills it
- Tacho works fine now.

I started to probe again and then I finally found something: ALL pins on the Bosch 2x2 module are shorted out - 0 Ohms (tested directly at the module). That would mean all cylinders are firing at the same time, right?
91' 940 B230FB+T M90
Brotkasten is offline   Reply With Quote
Old 02-09-2019, 02:04 PM   #2
300+hp on the shelf club
dl242gt's Avatar
Join Date: Jun 2002
Location: S NJ, a suburb of Phila.

Can you be a bit more specific? Are the pins shorted to ground? Are the pins shorted to each other? Don't forget the primary ciruit of a coil is very low resistance. Your meter may not be sensitive enough to accurately measure it. Coils do go bad and sometimes component substitution proves out the problem.
dl242gt is offline   Reply With Quote
Old 02-09-2019, 02:19 PM   #3
Board Member
bobxyz's Avatar
Join Date: Aug 2014
Location: Boulder, Colorado

I looked at the datasheet for the Bosch Double Fire Coil 2x2 0 221 503 407, and the primary resistance is a tiny 500 mOhms (0.5 ohms). Hold your probe tips together to get the baseline reading from your meter. If you measure at the connector, from center pin to either side pin, you should see a slightly higher reading, or measure across the 2 outer pins and it should be 1.0 ohms higher. The secondary resistance (plug tower to plug tower) is 13.3K ohms.
bobxyz is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump

All times are GMT -4. The time now is 12:15 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.