Recent content by AmpOverload

Many thanks for your clarifications and additional explanations! I learned a lot from your post! Your expertise far surpasses mine, so I consider myself a humble student here. :) I too have seen a VPW design that uses optocouplers -- specifically, this one...

It's always interesting to see the various hardware implementations of SAE J1850, so thanks for providing another option with your project/schematic! Page 2 of your PDF schematic shows "L2" with a value of "0 ohm 0805", which I assume is an oversight. Can you please clarify what that was...

I think I may have been misunderstood. I'm certainly not saying that there are no transmission-related DTCs! I'm simply trying to dispel the all-too-common misunderstanding that "code present" equates to "CEL illuminated". Having said that, after some research, I see that for the 2002...

Just a friendly reminder... The so-called "Check Engine Light" (CEL) is there only for EMISSION-related Diagnostic Trouble Codes (DTCs). I'd be checking for NON-emission-related DTCs, with software (either built into the scantool or used with a smartphone/tablet/laptop in conjunction with a...

Sorry for the low-res photo. I shrunk it to keep the uploaded file size manageable. It's certainly not a perfect gear, but there are many things I could do to try to improve it, including some I didn't even mention yet, like enabling "random seams". And, for the record, I did no cleanup...

Indeed! This is the 49-tooth version that I quickly printed last night, from an enhanced version of that OpenSCAD script I posted earlier: Even with no tweaks to the layer height or lowering of print speed (or any other techniques meant to improve quality/resolution), it came out better than...

Cool video! Thanks for sharing that! Even though I should have been doing other things since my last post, I just couldn't resist playing around in CAD for a while. I got a basic gear very much like the one in the model I'd linked to, all with just 3 lines in OpenSCAD (my design tool of...

Very interesting! I wonder if those (small) discrepancies would prevent the 3D gear from actually working? I compared various compatibility lists -- the 3D model's list (which, to be fair, I don't think was intended to be considered "complete") and a couple of actuators sold on Amazon that...

Very creative thinking... nice job! Although it's not an option for everyone, for those who own (or have access to) a suitably capable 3D printer and some suitable filament (probably PET-G or ABS), one might consider "printing" that gear. Having owned a 3D printer for about a year now, I've...

Actually, I think it's correct. Or, if it's wrong, it's widely duplicated incorrectly in various service manuals! For comparison, Ford/Lincoln/Mercury vehicles of that era use 40-100 degF as the limits (but they don't run the EVAP test while idling after cold startup). IIRC, several states...

Sorry if it seemed otherwise, but I wasn't questioning your Car Scanner actions or testing in any way. Your graph was very useful. I was highlighting the app's poor, inconsistent labeling of the X-axis time values. I consider that labeling to be a bug. I tested a beta version of that app...

Aside: What's up with those highly irregular time values on the X axis of that Car Scanner graph? Using your graph, my data, and math I won't bother to show here, your vacuum decay seems about 60% faster than the one I saw during careful monitoring of the automatic EVAP test on a 2004 Buick...

With the caveat that my testing was done on a P04 PCM (2004 Buick Century, specifically), the valves will retain their commanded positions as long as periodic Mode $3F ("Test Device Present") commands are sent. My Android app sends 1 every 4 seconds. (I don't know if they could be sent less...

I don't want to intrude too much on this thread since you're already being helped by @TJBaker57, who as all the forum regulars know, is supremely capable and helpful in these matters. I only want to suggest that you read this post of mine where I discuss some related issues, including the...

Excellent!!! Over the many years I've been learning OBD2 stuff, I'd say people clear codes needlessly about 4 out of 5 times! The vehicle will often clear the code itself, given enough driving cycles. And most people don't realize just how much stuff can be wiped out when they innocently...