Thanks guys, found it. Also found that my MAF module is defective, no 12v to MAF at the module terminals so not sure what to do. Right now I have it bypassed and it runs like a dream, but now the check engine will flash at me, in GM talk I know thats the big uhoh light. WinALDL is not showing any codes but the asynchronous fuel flag is active, not sure what that means so any help is appreciated. Also, the car will run fine stumble and die and thats when the dummy light starts flashing.
More pictures to come later today...

Edit: Flashing dummy light went away when I actually used the correct resistor in the ALDL port. And the code 33 isn't completly gone, it seems to come back when the engine tries to go into low idle, it stumbles, dies, and then sets the CEL. At this point I'm sure that my MAF module ia dead, ill check the burnoff function when it gets dark but there's no 12V KOEO, has anyone tried bypassing the module by wiring the MAF to a Ignition switched source?

Edit #2: Found whats left of the O2 sensor hanging from its plug when I went to pull clutch slave, luckily the O2 bung is empty, unluckily, its pretty rusty. Guess I'm putting in a heated O2. I'm wondering if this is whats causing the new code 33, the 02 always reads 0.451 to 0.455, doesn't fluctuate all that much.

Also, slave bore is rusted and wet, I think the master fine but I'd rather be safe then sorry, plus this way I can flush the system.

 

Ok so just to distill this down. When the car transitions into closed loop ie it adjusts fueling etc based on feedback, then it runs badly. He most important sensor in this feedback loop is the O2 sensor (it doesn’t have to be heated), so get a new one and screw it in. Another important sensor in the feedback loop is he MAF, ensure it is working correctly. In your case it sounds like there is an electrical problem, I don’t have a schematic for an 85 so i’d only be guessing if I provided help here. Either way with the MAF and O2 sensors functioning you will be most of the way there. I think WinALDL only shows the active codes but I can’t remember.
on the clutch I replaced the master and slave at the same time, I bought Delco ones and I have had no issues. Incidentally there was nothing wrong with them, I had a leak in the line that I couldn’t find. When I say nothing wrong with them that’s not completely true, they wouldn’t have lasted much longer. You should have a problem with the line between master and slave mine was due to some bastardizations performed during the RHD conversation.

 

Well, been trying to update since yesterday but have been getting a persistent Error 500 at the login page.
I started on a 4 wire O2 conversion, I keep 3 or 4 just in case one lets go in one of the LS powered cars, figured might as well make this one use the same sensor. The MAF circuit checks out, the car runs beautifully open loop on the MAF with the MAF power supply wired to a 12V source. Based off what you said and what im seeing i think since the O2 is reading a constant voltage because its broken, the ECM is flagging the MAF signal as faulty because ita programmed to prioritize the O2, just a guess because I'm not too familiar with these ECMs just yet.

I got the clutch hydraulics in, yesterday and took it for its first drive, I didn't get into it too much because of the fuel pressure issue, but I can't wait to get this thing on the road. Two issues I found with the hydraulics, the slave was stuck at the bottom of its bore, the new slave seemed to have a return spring so that it was always in the disengaged position with no brake fluid. The slave also had ALOT ​​​​​of wet rust in its bore, it didn't seem to be scored though. Second issue was the push rod was in backwards, ie pointy end in clutch fork, ball end in slave so I think I can trust the PO that the clutch is new. I tried the clutch spacer mod and definitely should have used the thicker half, clutch engagement is very high up, so im gonna slot the remaining piece so I can slide it in without having to remove the pin, my back hurts just thinking of sliding back in there .

 

Well if you have a heated O2 sensor and you want to wire it in well hats fine, it’s a better design anyway. With the power to your MAF I believe there is a MAF r lay in circuit that could be the culprit. You probably won’t get a O2 sensor code if the values just steps in the middle.
so the clutch rod was in backwards amazing, hopefully the PO did a better job of installing the clutch.

 

Yeah, relay is inside the MAF module behind the breadbox, not really fun to get at. There's something weird with the relay, it constantly clicks if I energize the MAF circuit, but will not operate under normal conditions. For the time being im going to cut the wire and wire it in to a keyed ignition source, hopefully within a couple of months I'll be able to do away with the MAF as a whole and move onto speed-density.

 

if the relay is constantly clicking well that’s a good indicator of a problem. TBH I think MAF cars have better street manners than MAP cars. For the track MAP is all you need. Your modern LS engine of course has both, when they tune them for big power the often do a MAFless tune.
So are you planning on switching to an EBL ECM?

 

I've had better luck with MAF based tunes on engines with weird intake designs, where the pressure inside the plenum doesn't correlate all that well to the volume of air entering the intake, but in this case, I'm primarily trying to eliminate a future point of failure and simplify the electrical.
I've been working on my own plug and play ECM based on the Speeduino project, I do want to keep it brief because I'm still unsure if this violates forum rules. The EBL is great for what it can do, but a Speeduino based board is less than half the cost and a few hours time soldering, plus, with a little tinkering I can get into the world of sequential injection, and remote coils for around the same cost if I wanted to. I'm planning on keeping it batch fire at first though, just until I get used to the car and learn its trends then start tuning it for power, I've been tossing the idea around of 3D printing a plenum and runner. Gets me nowhere close to what an LS will put out, but it will be fun.

 

Well that will be an interesting project. Hopefully there are some base tunes to get you started. I’ve found that the MegaSquirt forums are a god place to GE information because you he members are proud of their achievements and willing to share. If you are cutting up the harness you can pretty much do whatever you want. We have a couple of racing BNWs that we have converted to a MAP tune. We used old Haltech E8 ECUs because they are a couple of hundred bucks and work perfectly.

 

Good tip on the MS forums, completely forgot about them, ill have to check and see if anyone has a base tune after work. Those E8s look like a steal for a couple hundred bucks, the 32x32 table is definelty a big plus.
I keep forgetting to take pictures, but ill see what I can do today.

 

Yeah the Haltech E8 (and E11V2 same with more I/O) are great value. The interface is windows but a bit clunky. It’s designed for 32 bit PCs only but there is a different setup file available to make it work with 64bit PCs. Also the fuel tuning is done by pulse width timing instead of VE so a lot of “tuners” won’t touch them. We tuned our BMWs on a load cell dyno and were surprised at how well it performed.
Sorry that’s a bit off topic but the point is that if you want to tune it yourself and you don’t mind modifying the harness then there are lots of excellent options out there.
Edit: Also you need coil triggering power electronics. In the BMWs we run LS coils because they are both cheap and awesome.

 

Well, glad to report that my code 33 is finally gone and done with, I'm not happy with the way it was done, and I'd love to repair the burnoff module if possible. All that leaves is the fuel pressure issue, im going to run the remainder if the fresh gas in the tank out, and then remove the lines from both sides, and the filter and blow the lines out back and forth. Searching the forum it seems that the metal lines like to rust when sat dry and im wondering if this is enough of a flow restriction to cause the reduced pressure. Worst case, ill be buying a new fuel pump or making new fuel lines.
Second thing is I noticed the trans likes to pop out of second gear, and doesn't feel all that well engaged like first, is this a shift linkage adjustment issue of more likely to be a trans internals.

With that final issue solved, im going to begin documenting the completion of the C5 body kit as there doesn't seem to be too much information on them. I'm worried about overheating and airflow into the radiators with this body kit, but I may end up designing ducts to better guide the air through the radiator. If this is the case anything I do design will be on thingiverse and linked here.

 

i can’t remember the fuel pressure details but a new pump will help, blowing out the lines will help. If the pressure is high then blowing out the return line or breather pipe will help. Have you replaced the regulator diaphragm?

The jumping out of second gear can be a coupe of things but first thing to do is drain and replace the gearbox oil in the Super T10 section with good quality mineral gear oil 80W-90. If that doesn’t fix it you might be lucky with linkage adjustment but then it’s strip the gear box time.

 

Its a newish walboro 255 in it right now, its been my test pump for about a year and it fit in the brackets so I tossed it in there. I've got another pump I can test with to see whats what and I may end up doing that. It'll idle at 29 PSI, pull the vac hose and it'll sit at around 35, ive seen the pressure slowly dropping in the couple of hours I've run the car so im thinking the fuel filter is clogged up again, or there's alot of crap in the tank clogging the strainer or something. Does the fuel rail have a strainer in the inlet?
I haven't pulled the diaphragm yet, there isn't any gas smell on the vac hose so im not convinced the diaphagm is the issue just yet. The weirdest thing is if I pull the hose to the FPR, once it goes closed loop (pretty quick with the 4 wire) itll set the rich flag even though its at stock idle pressure. There's something im missing here, I'm wondering if my fuel pressure gauge is reading wrong.

Do the super 10s in these not like the synthetic oils?

Holy moly, pulse width tuning, I can see why alot of tuners won't touch them, ive heard the stories of how much work it is to rescale the fuel table.

 

Yeah there is max vacuum with the throttle shut and min vacuum at WOT. So with the vacuum line connected you have lower fuel pressure at idle and higher fuel pressure at full noise.

So the age old question of mineral vs synthetic oil. These days I pretty much always go for synthetic oil but I put mineral oil in my super T10 because that is what was recommended to me. The most resent Richmond Super T10 manual recommends a GL6 oil which I believe is synthetic.

 

At this point im convinced the fuel pump is underperforming, i took it for a drive around the block and all was fine for the first couple laps, after a bit it started hesitating everytime I got on the throttle. In the end it would accelerate, die while I was still on it, come back to life, die, and then just repeat. If I got off it and coasted in gear the engine would idle up fine after a couple seconds of being dead, definelty fuel starvation. Ive got a 300lph pump, but im worried that thatll cause it to run too rich and the ECM not be able to compensate, is that too much for these cars?

 

You can tape a fuel pressure gauge to the outside of the windshield and take it for a drive.

 

20PSI and drops with any throttle, also it seems that there no fuel returning, which makes me think fuel is barely getting to the regulator. When I first started running it there was lots of fuel returning, I guess filter and blow out the linew, run her dry and clean the tank?

 

ok we have identified the problem now we need to identify the cause. So yep fuel filter, the sock on the fuel pump, the pulsator on the fuel pump (if it has one replace it with a piece of submersible fuel line), blow out lines. That’s a start anyway, after that maybe check injectors (for stuck open).

 

No pulsator, read about them leaking so I ditched it when I replaced the pump the first time. I replaced the sock yesterday because my fuel pump came with two definelty some rust dust in the tank. Itll hold the 20 PSI it has overnight, so i don't think the injectors are getting stuck open or anything like that. Ill grab a new fuel filter and blow out the lines today.

 

ok well I think we are closing in on the issues. If the filter(s) is blocked with rust well that will be the issue. Otherwise it could be the regulator but you said no fuel was running in the return line so maybe not.