EfiniX
Well-known member
Last week, English Racing installed a new SD setup in my car. Tuned and dyno'ed and happy as all can be. I gained a small amount of HP and TQ at peak, but my power-bands across lower RPM ranges were vastly improved. I have a turbo setup comparable to a 20g, so my boost threshold is around 4000RPM's. Getting an additional 50HP and 50+ 'lbtq between 3200 and 4200 RPM's was/is awesome!
So yay for Speed Density.
I had a fun day after when the OmniBar sensor died, but they took care of it right away and even lent me a shop car to use for work while they were getting it fixed up.
so here's where things get interesting. I started experiencing serious idle surge after getting the car back. Not right away. I got the car back Thursday and it wasn't until I was sitting in rush hour traffic for 45 minutes on Friday that it started acting up. Now normally I'd go through the vFAQ on setting idle and dealing with surge (as I did with my MAF many moons ago), but it just seemed to perfect that it was happening right after getting speed density installed. I took a few videos of the surge happening (as I didn't have my laptop at the time). Pretty unsettling!
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&
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Of course, the second I got home, I fired up ECMLink and started logging. I didn't see anything out of the ordinary that evening, but the idle (which was acting up intermittently) was fine. So I resolved to log all my driving the next day to attempt to get to the bottom of the issue. It didn't take long. I drove to the gym in the morning and observed something quite peculiar in my logs. You can see here:
click
Turns out the hacked-up part of the wiring harness that connects to my coolant temp sensor was causing all sorts of crazy readings. I first noticed this because the according to the ECU, the car never got warmer then 186 degrees. I then noticed during some particularly spirited driving that my temp readings were fluctuating (quickly) between 150 and 203. Needless to say I pulled that section of the harness out, cleaned it up, re-terminated the connectors for the temp sensor (using solder, not crimp connectors like the last guy) and got it all back together.
So far, so good! Never would have thought to check the temp sensor. Thank goodness for ECMLink!
So yay for Speed Density.
I had a fun day after when the OmniBar sensor died, but they took care of it right away and even lent me a shop car to use for work while they were getting it fixed up.
so here's where things get interesting. I started experiencing serious idle surge after getting the car back. Not right away. I got the car back Thursday and it wasn't until I was sitting in rush hour traffic for 45 minutes on Friday that it started acting up. Now normally I'd go through the vFAQ on setting idle and dealing with surge (as I did with my MAF many moons ago), but it just seemed to perfect that it was happening right after getting speed density installed. I took a few videos of the surge happening (as I didn't have my laptop at the time). Pretty unsettling!
click
&
click
Of course, the second I got home, I fired up ECMLink and started logging. I didn't see anything out of the ordinary that evening, but the idle (which was acting up intermittently) was fine. So I resolved to log all my driving the next day to attempt to get to the bottom of the issue. It didn't take long. I drove to the gym in the morning and observed something quite peculiar in my logs. You can see here:
click
Turns out the hacked-up part of the wiring harness that connects to my coolant temp sensor was causing all sorts of crazy readings. I first noticed this because the according to the ECU, the car never got warmer then 186 degrees. I then noticed during some particularly spirited driving that my temp readings were fluctuating (quickly) between 150 and 203. Needless to say I pulled that section of the harness out, cleaned it up, re-terminated the connectors for the temp sensor (using solder, not crimp connectors like the last guy) and got it all back together.
So far, so good! Never would have thought to check the temp sensor. Thank goodness for ECMLink!
