The Central Hub for DSM Community and Information

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. This is where the DSM platform history is documented and archived. Log in to help us in our mission, and to remove most ads from the browsing experience.

datalogging help

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

COspeed

20+ Year Contributor
72
0
Jun 6, 2002
Colorado
So, I went out the other day and datalogged my car. I've been getting horrible gas mileage lately, and I thought by changing out the faulty coolant temp sensor and thermostat, my problem would be fixed. But this is not the case, and I'm still getting bad gas mileage...16mpg. My O2s read .92-.94 volts at WOT, which I know is pretty rich. But a couple months ago, I went from 22-24mpg to 16-18mpg and I hadn't really done any performance mods yet. Here's a list of my mods... Keep in mind that my mpg was bad before I put all these on.

Ported 2g manifold
ported turbine housing (14B)
ported O2 housing
ACT 2600 PP and street disk
Hallman boost controller
3" turbo-back with high flow cat
removed lower honeycomb and silencer from MAS

I'm not sure if I have a vacuum leak, but my gauge reads 12-13inHg at idle (keep in mind that I'm at 5300 ft altitude). I have some datalogs if anyone would like to take a look.

another thing... At knock counts of ~20, timing is being retarded to 11, 12, 13 degrees. Isn't that a little too much timing being pulled?

Also, the fuel trims are really out of whack... High is pegged at 140%, Low is also pegged, and middle is at 107%.

All the runs were at 14psi with 91 octane pump gas... Thanks for the help.

Erin








Erin
 
I looked at your first log and the timing and knock looked good at WOT. Timing being pulled that much with 20 counts of knock I would guess is normal. 20 counts of knock is a lot. For the gas mileage, your O2 sensor might be going bad. I started getting bad mileage awhile back and about a week later the car threw a CE light, logger told me it was the O2 sensor. Replaced it and mileage is much better now.
 
Add Value - Be Respectful - No Trolling - No Misinformation - Participate Often!
Support Vendors who Support the DSM Community

Build Thread Updates

Latest Classifieds

Back
Top