SUCCESS!!! Swapped A4 and G5 around.

Not sure if the '87 C100 is different from others, but the terminals are not interchangeable. One is bigger than the other. I cut the terminals off and swapped them on to the right wire. No big deal though, just a bit more work. Drop in the bucket compared to taking the harness back apart

Should be able to start her up this weekend

 

Odd

Ive made the same mistake and had to switch the terminals without issue

 

I'm lovin this man, you are doing great!! but if I was your son I'd be mad you didn't let me help. lol you are busting your knuckles so he can melt some rubber!! oh yeah

 

I'll take the trade off to see his face when he starts the car. I won't tell him what's been done and he won;t be able to tell until he turns the key. I think he will quickly forget that he might have any inclination of being mad once he realizes what has happened over the winter.

Pocket...just to confirm. In order to bypass the vss buffer box i need to connect two pins (F to C) and to kill VATS I need to connect the 2 heavy gauge wires at the starter relay. Right?

Also, happened to come across this while I was searching for some other stuff. This would explain why the terminals didn't fit.

 

A4 and G5 are the battery wires with F4 the main IGN. I must have switched A4 and F4 while you switched A4 and G5. Sorry for the confusion

Yes on the buffer box
http://www.austinthirdgen.org/mkport...SS_V8_vinE.jpg

Yes on the starter relay
http://www.austinthirdgen.org/mkport...m_pass-key.jpg

 

No need for apologies. I was the one that screwed up in the first place. You have been a great resource and help.

 

Anyone know if it's ok to run both vacuum lines for HVAC to the small port on the back of the intake below the brake booster vacuum source and then tee one off to the heater bypass valve? I'm assuming that the vacuum port (brass) on the front of an LS6 intake (pass side) should be ok for the cruise since I won't have the purge solenoid hooked to it?

 

IIRC, only one of those needs to be hooked up, the other went to the heater core diverter valve previously to open and close it. now which one, i dont have the info atm....

 

Can the heater valve be eliminated? From what I understand the A/C might not be as cold without it. The vacuum hose with the 90 degree bend is the HVAC.

 

You can delete the heater control valve. If you do, coolant will ALWAYS be flowing through the heater core while the motor is running. If you want to run a heater control valve, you need to watch which one you use.

This is my understanding...but I thought I read somewhere that its not good to cap off the heater outlets on the water pump. You need circulation from one to the other. Again...just what Ive read.

So if you want to run a heater control valve, you need one that, when closed, allows the coolant to go the valve, then turn around and come back without going up to the heater core. I found one that does just that, and mounts inline...vs having hoses going in different directions.

As for the vac lines...like was already stated, one is for the valve and one is the "supply" for the entire system. If you go inside and look at the soft vac lines, you'll see a purple and a grey tube running next to each other, and is attached to the hard lines. The purple is the supply, and grey is what actuates the heater valve.

I wrote up a thread on how to turn a non-heater control valve car into a heater control valve car...and show a few pictures of how all tha tworks...it might help ya. I wanted the valve in there to keep my a/c cooler...and it did make the a/c cooler.

Here is the thread on the vac hoses and the heater control switch and all. Not of too much use to you other than how it works maybe.

https://www.thirdgen.org/forums/tech...iring-vac.html

And here is the thread on the heater control valve I used.

https://www.thirdgen.org/forums/ltx-...-valve-ls.html

As I said...this is all based on the fact that the heater outlets on the LS water pump should circulate....if its a fact that blocking flow between the two is ok...then you can use whatever valve you want, or however you want to accomplish shutting off the flow to the heater core.

J.

 

Thanks. That's what I was looking for. I knew I had seen it somewhere but forgot to bookmark it. On my way home from work I started thinking a bit more about it. It should really work no different than the original did. I'll use the 3rd gen valve inline and run the vac line directly to it and the HVAC to the vac port at the back of the intake. I always overthink things

 

Better to overthink than underestimate and assume

 

So here's an oddity. I ordered 12628771 f-body oil pan, but the stamping on the oil pan is 12558899. No big deal as part numbers cross all the time and old stock is being sent as the new part number. But the problem is that a filter for a 4th gen f-body does not fit. After about 1.2 million trips to the parts store I finally found the filter I needed. A 5th gen f-body 6.2L filter. Not sure what to make of it.

 

That is pretty odd. At least you got it figured out.

 

New GM oil pans use the LS3 fitting for some reason. I ran into that on my pan and people said I was imagining things. Salvaged the fitting from the truck pan I was scrapping and the Fbody filter spun right on

 

Two reasons I didnt use a thirdgen valve.. 1) mine was long gone from my first swap, and my 86 didnt come with one. and 2) the stock one on my 87 had the hoses going out in different directions. so I wanted something that I could just cut my hoses right in the middle, and slip this in place.

But any valve that gives you the results, and you can make fit is perfect!

J.

 

Something clicked after the 4th trip to the store. I remembered someone telling me that the new pans use the LS3 fitting (it may have been you) so I got that one and sure enough it fit.

I ended up using something very similar to the one you used. After looking at both of them in person, the 3rd gen valve was not going to work the way I wanted it to. The 3rd gen only had 2 openings and was a bit bulky whereas the one I ended up using has 4 openings and is relatively small.

 

Went to the junkyard AGAIN to pick up another connector for the coolant temp sensor. They're pretty cool, they've gotten used to me looking for crap all the time so they just give me a set of clippers and tell me to get what I need....and for free

Anyway which one of these three wires is the one for the gauge? I assume the two brown get spliced into 1 wire and then into PIN F5 on C100. Should the Black wire still go to the PCM for low reference?

Sorry for the crappy cell phone pic.

 

 

Perfect. I think "thank you" is starting to lose it's meaning for as many times as I've said it

 

This is turning out to be the swap from hell. Right as I was getting ready to fire her up...I better do one more double check....and I forgot the effin' tranny cooler lines. So drop the tranny for a third time. I'm not sure what is going on with the lines but they do not fit worth a crap, so now I have to go have custom lines made. Oh and the hawks x-member, not sure if I got a bad one, but the fit sucks. Had to drill a bigger hole for the tranny bushing pin to fit. Ugh...bad start to the weekend. Anyway just had to vent.

 

I can draw up an AN6 line diagram with PNs if it'd help the process

Also, you dont have to drop the trans to get to the lines. Maybe lower the crossmember or pull the pass side header at the max. I replaced mine with everything still installed

 

If you have the part numbers handy that would be great. Otherwise no need to make special concessions. If you can tell me what the thread is, I'll get on summit and order up some stuff. I don't want to crawl under the car again today. I need a time out

I had to drop the tranny (partially) because there was no way in hell I was getting a tool at those fittings. Went down to the local parts store and got some new lines that were total junk. Can't make any sharp bends or they kink.

 

I drew them up but never uploaded them to photobucket. The trans fittings are different for the rear trans fitting on the new style 4L80E's. Rest fit

Trans takes 1/4 NPT, radiator 1/2 x 20
45* hose ends on the trans, rad upper is a 90* and 45* lower

You can mix/match straits or 90*s for all of it but those angles fit best

edit: PNs in the diagram arent correct for the trans side. They take 1/4NPT which is SUM-220647

 

Thanks Jon. This will be a welcome break while I wait for parts

 

Im doing the waiting game too. Headers, LS2 timing chain, pushrods, injectors all in the mail

About to order a new fuel system with all the AN stuff along with a full list of silicone couplers too. Ouch

 

Updates?

 

Got her all put back together. Had a delay because of the waiting game for parts. My parts showed on Thursday and I got to work today. Got some wrong fittings that I got sorted out (sort of). I ended up getting a separate tranny cooler instead of running it to the radiator. Should clean things up a little since all of a sudden things are getting a bit cluttered.

Tried starting the car but no luck. Not sure if VATS is causing this but there is no fuel at all at the rail. Guess I'll trouble shoot that tomorrow

Which two wires am I supposed to connect? The yellow and ? I don't see a dark green and I have both tan AND white but no tan/white.



What is the yellow and purple plug supposed to be plugged into? I found it unplugged



Shot of the tranny cooler. Have to find a good spot to mount it.



Shot of the subframe connectors. Should stiffen things up a bit




Oh, almost forgot. Another one of those things that was supposed to fit, but doesn't....the torque arm mount does not line up with the holes at the transmission, go figure. Tranny is out of a '99 Trans Am. Anyone else run into this?

 

I think that is the clutch pedal switch

 

Does the key have the pellet in it? IIRC 87 was before VATS

 

Correct.. 89 was first year for VATS, and I think GTA's got VATS in 88.5.

 

That would explain why I can't find the wires Ok so I guess my next stop is at the fuel relay to see if that things is wired right. The walbro should be audible when it turns on, shouldn't it? I can't hear it.

 

Most of the time yes.

 

I noticed that the fuel gauge is not alive. Wondering if the sender took a dump too? I really don't want to have to drop the tank again.

 

Both are not working. Possible bad ground?

 

Maybe. But everything else is working. I'll have to do some trouble shooting tomorrow.

 

You'll love those subframe connectors, I know I do! I have absolutely no wheel hop

 

I like that you can bolt them in first before you weld them. Weldning should be a breeze.

 

What kind of voltage should I see across the fuel pump relay from 30 to 87? When the ignition switch is turned on I should see 12ish volts, shouldn't I? If I'm not, then what is the issue? Ignition and fuel relay are grounded on the same ground and when checking with a volt meter the 30 to 85 (85 being ground) I get about 12.22 V.

 

Should be 12ish volts just on the battery, 14.4v when running. I shot you a PM

 

Im not 100% sure what you did for fuel pump wiring... But I would be checking grounds if you messed with any of the original harness. I had an issue with the ground under my rear seat, causing my pump not to run on swap #2. Had me scratching my head for quite a while.

That purple and yellow wire is in fact the clutch safety switch. Not to be confused with the clutch anticipate switch...which kills cruise control, and also tells the PCM that the clutch is in on an LS car. Those are the SAME wires that are up at the neutral safety switch for the auto shifter. In both my 86 and 87...the clutch switch wires were already there. With different plugs.. As far as I could tell...82-86 had one style of switch, then 87-02 used the same switch. Since you are going with an auto...just tuck those wires away. If you ever switch to a manual trans, you would cut the wires at the neutral safety switch, twist them together, then use those wires by the kick panel for the clutch safety switch.

Those SFCs look pretty nice... S&W seems to be a great company. Ive been going back and forth with them for awhile about a 8pt roll bar. They arent too far from me and Ive seen the shop. They build some nice stuff.

J.

 

That connector he pictured should plug right into the neutral safety switch, no cutting and hacking necessary especially since that is a piece of safety equipment. Since he already has the wire and connector all the more reason to use them with the $10, or so, switch. My 91 didnt have that extra wire/connector and it was a pain to pull the neutral safety from over at the auto selector in the middle of the car


**Edit** I read what you said wrong, but the NSS from the auto and manual should be in parallel since the manual stuff has nothing connected on the auto car, still shouldnt need to splice anything

 

Since my car was carbureted I built a separate fuse block and eliminated all the original stuff. I think the only stuff going through the C100 at this point is only the light stuff and ignition, starter, oil pressure. The rest is housed in the new fuse block. The new fuel pump relay is grounded in with the grounds from the truck harness behind the heads and goes through pin D on the C207.

I tested the grounds and they are 0.04 ohm, so continuity is good. I'm not sure what the deal is but the pump is not engaging and the fuel gauge is dead. Only thing I can think of at this point is to make sure the connector at the tank is properly connected. And if that ain't it, then I have no idea what to look for next.

 

Perhaps I was a bit wordy with my response. That happens since I can't work on my car and I get bored haha. But that's basically what I said. I was just sort of feeding him some info on the wires in question.

As for your fuel pump issue...i think you are at a spot now where you just have to triple check it all. Only takes on broken wire or crap connection to muck up the works. Also...im not sure if you tested the pump, but hot wiring it to check it might not be a bad idea. Its rare...but they can be DOA. Its happened before.

Good luck tracking the gremlin down. You're so close!

J.

 

We are all cheering for ya!

 

When I was swapping my pump I hotwired it about 4 times total before I put it in. Once to make sure it worked, second to make sure my my soldered in tank connections were good and a couple more times because I leave nothing to chance.

 

Did you get this sorted out? You have to use the torque arm mount from a 4th gen because the 3rd gen one has a different pattern. The 3rd gen mount has a completely different bolt pattern and does not crossover.

 

I ran into the TA mount issue because I never heard about the mount being incompatible

Welded a small tab onto the 3rd gen mount and reused the rearmost hole so Im using 2/3. No issues so far

 

Thanks for the reminder. I added this tidbit to the LS1 swap sticky.

 

Thanks

Yes and no. No in the sense that I am not dropping the tranny back down to use the 3rd gen mount. I'm not sure why but the 700R4 leaves you with just enough room to get the bolts in and out and the 4L60E not so much. There is no way in hell that the bolt will go back in. So I'm forking out another couple of hundred bucks for the SWracecars torque arm since I'm using their sub frame connector and it has the mount built in. What's another few hundred in the big scheme of things


I've checked the voltages and the resistance at the fuse block and it all reads the way it should. Grounds are good.

Tonight I'm checking to make sure the connector is seated properly back at the tank.

Question on testing the circuit from the relay to the connector on the body side of the tank. With ignition in "off" the circuit should be closed right? In that case I should be getting some random number for resistance. With ignition turned to "on" the circuit should open and resistance should be close to 0 ohm, but only for a few seconds, right? If all this is true I can at least eliminate that portion of the wiring.

Now on to the pump it self. I'm assuming the pump and sender are a closed circuit with the ignition in "off". With ignition "on" I should again get an open circuit, right? So if all this checks out, the pump and sender is good.

Lastly, hot wiring the pump at the relay did not work. So I should be able to take a couple of jumper wires to the connector at the tank and try, right?

Thanks for reading my book....sorry