That blows. Be sure to get an entire ACDelco or Delphi sending unit and replace the filter. Not just a pump.
That blows. Be sure to get an entire ACDelco or Delphi sending unit and replace the filter. Not just a pump.
Well before dropping the tank, I decided to check the fuel pump relay, and it turned out to be the culprit. More than 14 years in service. Replaced the relay today. Hopefully will do some logging this week.Originally Posted by SiriusC1024
Excellent
Well did some logging with the latest tune today. I have got more observations as listed below:
- The bucking issue has become worse. when I put in 1st gear, start rolling going into a curve, I get this bucking below 20 mph. This happens also happens when in 2nd gear below 20mph. Also, bucking happens when making a u turn at a stop light.
-Another thing is more frequent idle drop below desired idle rpm. Also, before stopping the log I started revving the engine while in stopped condition, the idle drops below desired idle rpm, then picks up to 750rpm.
- The worst dip I had to the extent that it dipped and engine died after making a turn while slowing down in 2nd gear. You will noticed this a few minutes before ending the log.
- Also, engine surges when IAT went above 100 deg F.
I think the idle might have become worse because of the desired idle change from 800rpm to 750rpm, and maybe the timing.
Just realized that I forgot to reset the LTFTs prior to scanning. Could this be the cause for the above issues?Thanks.
I would say load SD_2 and apply changes to main spark in the opposite direction of SD_3 to see if that has a positive effect. From the log at 13:13, where the idle dips, it looks like the engine does need more spark even at 1200rpm. Make sure to update changes at base spark to the idle spark tables.
You'll be able to make changes a lot quicker on your end to see what effect settings have on the bucking issue.
Thanks for the input. Honestly I am still learning as mentioned before, and did not get exactly what you meant by ?applying changes in the opposite direction of SD_3?
However, my biggest concern is the surge issues when IAT goes high as noticed in the log and idle dip because of it. Not sure how to overcome this issue.
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