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Perhaps spotting or narrowing down the EOT at which it goes from slug to normal speed would help. That would also give you just one parameter to watch since we could chart the data log and base the slug to normal change off that one data point.
Let us say that you observed at 141° EOT the truck goes to normal. Once the data log is charted, we could find the 141° EOT measurement and mark the chart at that point in time and attempt to find anything else out of the ordinary prior to that point. Also, if you notice this slug to normal change around the 140° EOT mark a couple of times in a row, that would likely narrow down your key PID.
Next would be to ensure all of the PID's and sensors are reporting to the PCM as they are designed to do. I recently saw this with a CPS that was intermittently reporting and I could not see it with my own eyes and live while cranking the truck or waiting for it to stall while it idled for an undetermined amount of time.
Thanks again Sous. I ordered everything (hopefully everything lol) to do the hutch/harpoon mods. Whether or not that’s my problem it’ll be nice to finally get that one off the to do list. Appreciate all the info you and others have posted up on doing that mod it’s been extremely helpful. Prob get going on that next weekend.
As for EOT I’m really leaning towards that being the culprit. I’ll watch that one close in the morning.
Alright fellas, I’m not good with computer stuff so I didn’t get a good screenshot haha.
EOT was/is spot on as the engine goes from cold to operating temp. What I did notice was the ECT started out at -150*F and stayed in the negatives for quite awhile. Normal or is my sensor suspect? Wonder if that would limit fuel when it’s negative degrees?
Alright fellas, I’m not good with computer stuff so I didn’t get a good screenshot haha.
EOT was/is spot on as the engine goes from cold to operating temp. What I did notice was the ECT started out at -150*F and stayed in the negatives for quite awhile. Normal or is my sensor suspect? Wonder if that would limit fuel when it’s negative degrees?
ECT doesn't actually go to the PCM on auto transmission trucks before 01 I think. I'm not sure if it's the PCM or the scan software or what but they all still report a phantom reading that usually starts out ridiculously low and ends up scarry high.
ECT doesn't actually go to the PCM on auto transmission trucks before 01 I think. I'm not sure if it's the PCM or the scan software or what but they all still report a phantom reading that usually starts out ridiculously low and ends up scarry high.
I can confirm the ECT is a phantom reading on my 2001 auto. The PID is in the PCM choices on the edge monitor, but it has no real readings.
I can never remember the details of which trucks actually had this going to the PCM but I’m thinking it was 02-up manual trucks.
I can confirm the ECT is a phantom reading on my 2001 auto. The PID is in the PCM choices on the edge monitor, but it has no real readings.
I can never remember the details of which trucks actually had this going to the PCM but I’m thinking it was 02-up manual trucks.
Jason got it right. ZF6 manual trucks of the later years are the only ones that report ECT accurately to the PCM. For example, my 2000 ZF6 is a phantom reading as well.
Who’s tunes are you running, and did you properly switch to 00 Hydra setting during your testing?
Reason I ask is that some tuners like AA purposely hold back fuel until oil is up to temperature.
Very good points.
Originally Posted by Sous
Jason got it right. ZF6 manual trucks of the later years are the only ones that report ECT accurately to the PCM. For example, my 2000 ZF6 is a phantom reading as well.
Thanks for the confirmation. And it looks like I may have got that “phantom” description to stick.
I need to check fuel pressure like suggested earlier but dang I’m having trouble finding the time. I’m hoping next weekend I can drop the tank and perform the Hutch/Harpoon mod. We’ll see what the weather does. I get to do it in the driveway—ugh.
Pulling the bed is an option too. Not sure which is less of a PITA though. Pull the bed... Drop the tank... Pull the bed... Drop the tank... Yeah hard to say. They both sound like so much fun.
Mine don't like to get up and go until the Oil temp is about 90ish...
I prefer to not push it, until the oil is at least over 60*
This right here. Most people get annoyed when riding in old green. When she is cold, basically just let her roll on her own to get going. Take alternative routes to stay out of traffic until she gets up to temp. You can definitely tell the difference between cold and warmed engine. it is as 25 year old truck that still runs great and want to keep it that way.
Thanks fellas, I’ve been going back and forth on pulling the bed or dropping the tank and I’m kinda torn. I have some gooseneck stuff in the way so I’m leaning towards dropping the tank. Ugh either one sound awful haha.
Fan clutch is good to go. It comes on and off when it should.
Yeah I don’t really hammer on it when it’s cold I just have this annoying 55mph road that I have to turn onto after work and sometimes getting out in traffic is a little scary. I’ll just take her easy, wait for a big gap and let people pass me if needed.
