OBDII conversion - troubleshooting time
#71
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Alright, the startups are now fairly consistent. It'* one helluva smokeshow when I let it get into some boost though...majorly rich, Also probably because of the fact the gas that is in there has been there since....October....when I did the tank and pump changeout. But, it starts up every time I do it
Gotta send some emails and PMs out...time to move on to dialing-in.
Gotta send some emails and PMs out...time to move on to dialing-in.
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IF I do a 94/95...that would be better done as an internal PCM setup. In fact, no external wiring to the engine needs to be done, other than the addition of a MAP, the 2nd knock sensor, and AC pressure sensor IIRC. Linear EGR and trans temp are already there, along with everything else. (Remember, I dealt with a 1993, which didn't have that, so an external PCM made more sense).
The more I think about it, the more I realise this mod would benefit the 94/95 crowd the most. Not only is most of the sensors and equipment already in place, but the fact that those PCMs are becoming more unreliable, and harder to come across in working condition. Plus, it eliminates needing a special scan tool to read them.
I suppose...if I wanted to streamline things...1992/93 conversions would require switcing to the 94/95 harness (both engine AND firewall, IF someone wanted to keep the factory fuse and relay connections...), along with the equipment requisites. But, no matter how much streamlining I do, there is still going to be some cut-n-splice work invovled. And more than likely, it will be a permanent modification (something few people consider).
Would this benefit everyone? No. Normal (read unmodded) daily drivers probably wouldn't see much improvement aside from a slightly smoother idle and somewhat quicker throttle response. Nothing a normal chip programming couldn't do. But for those of us that are *ahem*, highly modded...then this mod might be worth looking into. (I wouldn't consider myself highly modded btw...all I have is a ported lower, ported and polished SC case w/gasket matched TB, 2.2 pulley, slightly opened up exhaust ports, high-flow cat, high-flow fuel pump...all on top of an L27 core).
Even when I get access to what I need to tune this, it will be a while. I *still* have to get new tires, *may need to* replace the front suspension again, 4 wheel alignment, AND get a wideband O2 (thinking JAW since I'm a cheapskate). So it'* mainly going to be idle trims that I will be working on in the interim.
EDIT - Got my interface for a good price
The more I think about it, the more I realise this mod would benefit the 94/95 crowd the most. Not only is most of the sensors and equipment already in place, but the fact that those PCMs are becoming more unreliable, and harder to come across in working condition. Plus, it eliminates needing a special scan tool to read them.
I suppose...if I wanted to streamline things...1992/93 conversions would require switcing to the 94/95 harness (both engine AND firewall, IF someone wanted to keep the factory fuse and relay connections...), along with the equipment requisites. But, no matter how much streamlining I do, there is still going to be some cut-n-splice work invovled. And more than likely, it will be a permanent modification (something few people consider).
Would this benefit everyone? No. Normal (read unmodded) daily drivers probably wouldn't see much improvement aside from a slightly smoother idle and somewhat quicker throttle response. Nothing a normal chip programming couldn't do. But for those of us that are *ahem*, highly modded...then this mod might be worth looking into. (I wouldn't consider myself highly modded btw...all I have is a ported lower, ported and polished SC case w/gasket matched TB, 2.2 pulley, slightly opened up exhaust ports, high-flow cat, high-flow fuel pump...all on top of an L27 core).
Even when I get access to what I need to tune this, it will be a while. I *still* have to get new tires, *may need to* replace the front suspension again, 4 wheel alignment, AND get a wideband O2 (thinking JAW since I'm a cheapskate). So it'* mainly going to be idle trims that I will be working on in the interim.
EDIT - Got my interface for a good price
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That interface is awesome! I have a plan to build a carputer into my interior and then use it to tune my car. If I could do something along the lines of what you have done, I'd be all set to tune with my touchscreen! That would be a little bit too cool.
#75
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Whelp,the DHP tuner wouldn't do anything with the junkyard PCM....it could read it, but couldn't flash it. So...since it'* gone as far as it can. it'* time to take the PCM back to the junkyard. It served it'* purpose well enough I may wait until I get the HP Tuner in the mail before I do anything else, though I doubt it can do much with that PCM either.
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Originally Posted by sandrock
I may wait until I get the HP Tuner in the mail before I do anything else, though I doubt it can do much with that PCM either.
Last question for you Brad... what'* the PCM'* service pn/broadcast code (tag on the PCM, usually in the form "16xxxxxxx AAAA"
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THATS a good question. I may have to borrow someones car with a working VATS/BCM to allow that to happen.
I'll get those numbers for you tonight. I'm at work right now. You got some info for me?
EDIT - Re-read your post Curt. The VATS, as you predicted, changed in the way it operates between the older and newer PCMs. New style PCM needs a "tone", presumably from the BCM, before it gives the go-ahead for runtime. Older PCMs just need to be grounded by the VATS module from what the schematics look like. So, in short...no, my VATS system will not interface with the new PCM.
I'll get those numbers for you tonight. I'm at work right now. You got some info for me?
EDIT - Re-read your post Curt. The VATS, as you predicted, changed in the way it operates between the older and newer PCMs. New style PCM needs a "tone", presumably from the BCM, before it gives the go-ahead for runtime. Older PCMs just need to be grounded by the VATS module from what the schematics look like. So, in short...no, my VATS system will not interface with the new PCM.
#78
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Aaron came over again tonight to try something else...something his roomate worked on. After about 4 or 5 writes to the PCM, we now have what amounts to the 1997 L67 tables, with injectors set at 29 lbs. After doing its learning (and yes, VATS is disabled), it starts at the first bump of the key, and idles butter smooth (well, not QUITE butter...more like margarine, but it still idles well...and I think it'* slightly better than the '93 PCM). It still isn't tuned right, and we found that the TPS is wired backwards
But it is affirmative! I'll get a video of it tomorrow once I rewire the TPS
But it is affirmative! I'll get a video of it tomorrow once I rewire the TPS
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Trial and error; these things never work right the first time. An interesting note on these pcm'*...it seems that the VIN K and VIN 1 pcm'* are the same physically, it'* the code inside that makes the difference. The pcm that'* running in there now is a VIN K pcm from a 97 Olds 88, reflashed with an essentially stock 97 SSEi bin file, and as far as I could tell everything is working normally...or as normally as you could expect at the moment.