I thought the egr went to the egr control solenoid. Then went to basic vac? The only line coming from my charcoal canister(still old one) went to basic vac.

 

vaclinesformyiroc.jpg?t=1325217059

Not according to this diagram. My vacuum lines were chewed, but there was a T sticking out of the throttle body where the egr solenoid should connect. This implies that this diagram is correct? If there's a better way to do things, I'm all ears. I just want a well running car that csn pass CA smog.

 

Mine is a 91/92, and after looking at that diagram, I see they are different.

 

so running the LS1 tank with a tpi, i need to disable the LS1 fuel pressure regulator in order to allow the regulator on the fuel rail to regulate the pressure. i am not finding how to do this. can someone help me?

 

You just remove it in from the sending unit.

 

So anyone know how to hook up egr and evap for an 87 tpi system?

 

Okay, so I learned from a different thread that the egr and evap systems are in no way interlinked, GM just didnt want to drill another hole in the tb. So my problem is a lot simpler now.

My revised question is: How do I hook up the ls1 evap/charcoal can system using vacuum from a 305 tpi? I need to be CA smog legal..

 

In a nutshell, the set up will not work, for a multiple reasons.

 

Those reasons being...? I thought it was a matter of running vacuum back there and wiring up a solenoid?

 

You have to also wire in the fuel tank pressure sensor and the fuel level sensor to the ECM, I think other people have said you have to have the dash cluster too, but no one has been able to confirm that

 

You need the 4th gen cluster feed to get the evap working. The fuel gauge is part of the config and because its a different ohm sweep than a third gen gauge, it doesnt work as a result.

Long story short, sure its doable, anything is doable, but there is no "how to" recipe here to follow. Care to figure it out and write it up? Would help a lot of people who also wish to retain the evap stuff.

The charcoal can on a 4th gen tank is light years better than the stock third gen system. Its mounted right on the tank and handles vapors from fueling up and off gassing analog, theres no vac or electronics needed.


LMAO *treed*

 

*for your application only (305 engine)*

Will require a separate stand alone PCM, and in theory OBD2 diag port and a second (or integrated) check engine light.

Fourth gen or after market fuel gauge. #

An engine bay mounted solenoid in addition to the everything on the tank.

The possibility of failing emissions if the inspector notices the lack of the stock canister. I am assuming this is the reason for the swap in the first place.


# The PCM requires a fuel level input. You will have to figure out what device sends this information. If its the gauges, then fourth gen gauges must be used.


Now, if you are willing to swap to an ls1, fourth gen gauges, and tank it would be easy.

 

My overall reasoning for using the new tank was that I needed a new fuel pump, the old tank was filled with 10 year old gas, and the ls tank was only a little more expensive than buying a new pump for the old tank. Plus I get some weight savings, get to get rid of the charcoal can up front, added tank capacity, and an easier time if I ever gather enough money to do an ls swap. It seemed like a good idea for many reasons.

I guess the real question is that if the charcoal canister functions without any vac or wiring (a couple pages back a member by the handle of Dale mentioned something about hooking up the charcoal can to vacuum, true or not?), do I even need the evap system to pass CA smog? But I guess that's a question for the SoCal board.

 

The fuel level sender goes directly into the ECM and the dash is fed by serial input from the ECM, not the other way around. The ECM knows the fuel level before the gauge on the dash does.



There was ONE guy who said he was getting the EVAP to work without the cluster, but he was never able to "prove it" for everyone. He said he could watch it be commanded on what ever scanner or program he was using with his setup.

I will be doing a 4.8 into my car in the future and I really plan on trying to make this all work, even thought I don't HAVE to. I am still trying to figure out how I would get the fuel level to work on the stock gauges still

 

Nice job guys !

 

My fuel gauge does not go thru the ecm. There is a grand prix part you can buy, replace the 4th gen one with it, and send it strait to the cluster, bypassing the ecm.

 

Well I had a 4thgen tank installed, with a dual fuel pump setup from lonnieP. Its totally compatible with my fuel gauge, but the shop would never explain how the gauge or evap works. I asked them at least half a dozen times and they said it worked though lol

 

So I'm back at it, I really need to pass CA smog legally. Would prefer to continue to use the plastic tank. Anyone have any ideas as to how I would make the the older third gen charcoal can/evap system work with the newer tank?

 

In simplified terms, It wouldn't work. The third gen system would just be a redundant system.

Simply swap over the engine, trans, fuel tank, wiring, and gauges from the fourth gen donor.

The fourth gen tank tank is self contained using a built in charcoal canister.

Scooters post #164, shows all the input signals the PCM needs to have for evap full function. The reason the gauge cluster is needed is that the fuel gauge for the fourth gen is a different ohm sweep then the third gen. You must retain the fourth gen fuel tank sender because the pcm needs that exact ohm sweep for function.

PM sent with my #, call and I will explain at length.

 

One thing Im trying right now, that i havent confirmed works in the car but works with benchtesting is this.

On the back of the fuel gauge is a 90ish ohm resistor (I think its 88.6 ohms or something)

I replaced that with a 240ohm resistor (assuming this resistor = resistance at full)

and for empty, I got a 40 ohm resistor and placed the needle at empty.

Im going to hook up the PCM and the gauge to the same wire and see if it works in tandem with the PCM.

Someone might be able to try this before I get my car on the road.

 

I finally made It to my fuel tank swap.

1990 iroc 5.0 vert

parts are from a 2001 WS6 trans am A4 car.
fuel tank
plastic lines
metal lines

I plan on cutting the metal lines up near the front and convert to braided steel to make them fit nicely.

I have the 2001 Trans am cluster that I plan on using but with the 3rd gen dash still. Hoping to get the fuel level to work as well. maybe evap if possible.
Just need to go through the posts and find out the 3 wire to 4 wire harness.

once the tank is done ill install the 4th gen rear end and move forward to the engine and trans.

 

I know this is a very old thread, but it has good info. Here's my problem and I'll probably start a new thread to filter out a lot of reading. I'm installing a 2002 Trans Am plastic fuel tank. It has all the fittings. I'm installing a 95 Chevy Caprice LT1 in my 83 Camaro. After reading this entire thread I've learned that the return line doesn't have to go all the way up front. BUT my LT1 fuel rail has a fuel regulator on the fuel rail.

[IMG][/IMG]

The fuel goes into the fuel rail and comes out at the regulator then back to the tank. If I remove the regulator on the fuel rail, how do you plug the end off? Can I just leave the regulator on? Or should I just run the return line back to the tank using the evap line in my 3rd gen Camaro? I'll be using the PCM out of the Caprice (donor car) and it has provisions for evap. Are they comparable? Do I still need the $th gen fuel gauge?

 

Why not yank the FPR off the fuel pump module in the tank and keep the one at the rail? Then you'd have correct pressure. I had the corvette regulator all plumbed in before I did the 4thgen tank and that's what I did.

 

How do you do that? I haven't had the fuel pump out yet.

Here's my tank:
[IMG][/IMG]

 

When you pull the fuel pump out you'll see above the module itself the FPR held in with a small clip. Just push it off. I don't know what the LT1 takes for pressure but the LS1 uses something like 60psi which may be a bit much.

 

42-47 for the lt1 use that regulator on the fuel rail

 

Thanks for the info.

 

What has everyone done with this hose?
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I think that hose was supposed to go to vacuum as it comes out of the canister. The middle outlet on the fuel pump runs to the tube that comes out of the tube coming out of the black circular thing and then runs to the canister (vent portion). My LT1 has a canister fuel solenoid valve close to the throttle body. I'm trying to figure out which solenoid I should use.

 

Anyone? Can it be vented to atmosphere?

 

Yes it can. That is evap and it is set to open which goes through the charcoal

 

After reading through this and a bunch of other threads, I plan on using an LS1 Tank in my Carbed 84. I have already retrofitted my factory tank with a walboro 255 and am using a mallory return regulator.

1. Can I simply use my existing return line and hook it up to the return port top of the sender assembly? This would essentially make it a return-style like my factory set up.
2. Can I leave the LS1 Pump and Regulator in the tank and continue using my mallory Return-regulator? Or should I take out the in-tank regulator and just use my mallory unit?
3. My current plan, is to use summit brand AN adapters for the tank and compression fittings on my factory hard lines in the back. I will do the same in the front with the compression fittings.
4. I want to keep the evap canister hooked up, but I obviously have no provision for the solenoid. DO I need the solenoid or can I just leave that electrical connector disconnected? As my current cannister is hooked up to my PCV system vacuum lines, do I need to run those lines to the back of the car to connect to the cannister to make it work right?

 

Here is my understanding of the evap system: using the plastic gen 4 tank, the pcm or ecm takes inputs from the fuel gauge, TPS, temp, VSS to decide on when to open the fuel canister purge valve solenoid. This allows the fuel canister to vent it's fuel vapors to the throttle body and then to the combustion chamber. If you just don't connect the wiring to the canister system, I don't think the canister can releave itself and the system will not function. Now you might smell fuel. This is a simplified version, but I hope it helps. The factory service manual has a good explanation of how it works.

I'm swapping a 95 LT1 into an 83 Camaro and I'm trying to work out the install of the plastic tank myself.

 

Thanks for that.

I've got everything lined up to purchase except a tank. The yards around here are picked clean or are damaged from rear end collisions and Ebay hasn't been any help. I'd like to keep the system hooked up if I can make it work, somehow, with my 84's limited Evap system.

 

We just have to figure out how to activate the purge valve. I'll be using the pcm out of the 95 LT1 and it has evap controls. That means I have to make sure the inputs into the PCM are there. It takes a nerd to figure it out.

 

The issue is, retrofitting into an older car that doesn't have that command. I know I've seen it where some people are trying LS1 ECM's running TPI motors but I don't know how backwards compatible that is, even with custom tuning. I wonder if you can do something like that in an even older car.

My car doesn't have any evap controls that I know of. It's got the charcole cannister and some vacuum lines. I wonder if there is a way to program a switch to periodically purge it?

 

If your car has a canister, it has some means of venting the canister to the intake. In my 83 Camaro there is an ecm that controls the metering valves in the quad jet carb. But it also has some way of controlling the purge valve to vent the canister. Our question is can the LT1 or LS1's ECM control that purge valve? In my case can the LT1 ecm be made to control the newer 2002 eval system? I, too, thought about "manually" turning on the purge valve, but I quickly dropped that idea for a variety of reasons.

 

I too have the ECM, as our base systems are nearly identical. I'm just not sure to what extent it controls the evap system. I know it controls part throttle metering but the EVAP is all hooked up via vacuum lines. I can't find any electrical control for it.

From what little I've read about the solenoid, it isn't only the ECM that tells it when to purge. Maybe, if you get the small bits that read it, in conjunction with the ECM, that would work? Might need an engineering degree just to figure out where it all goes.

 

Looking at your tank, the middle nipple that comes out of the fuel pump needs to run to the nipple on the line that goes into the canister. Otherwise, the canister is not connected to the tank and vents to the atmosphere. Look at my tank picture.

 

I don't have an LS1 Tank yet. I haven't been able to locate one that isn't going to cost me North of $350 with shipping. I'd like to stay in the $100 shipped range. hehe

My current tank has the vent line hooked up as it's supposed to be.

 

There are lots of forums you can look for the tank. I paid $100 plus $67 for shipping. It is a 2002 TA.

 

I will keep my eyes open.

 

Do you guys know if there is a way to fix the stock fuel gauge to work with this tank? I know I could modify the sending unit, but I currently have the gauge sluster sitting on teh counter at home.

 

There are three different threads that describe this process. Do a search and they should come up for you.

 

I was using my Camaro service manual the other week and ran across these pages that I thought would be a good addition to this thread:



M

 

^^^^^ Good information detailing how it works to a degree.


The purge canister solenoid can only be controlled by the relevant model ecu, be it camaro/firebird with that feature (as they are the donor for the tank), it takes various inputs from tps, maf and lots of other details and opens/closes it accordingly.

You can't run this from the lt1/ls1 ecu that does NOT have purge canister vent valve output, the evap purge is a different item all together.

Short of having a funky micro-controller that takes the inputs from the same devices a standard plastic tank ecu does and know what values it adjusts at, the simplest way to do this, is to get yourself a charcoal canister from a pontiac gto 04-06, remove the purge solenoid as the gto's have a direct to air purge without solenoid, then hook it up as you would normally do, it will still have the tank purge line into it and the line to the engine to purge, as well as an atmospheric vent.

Picture like so with the GTO Charcoal Canister fitted.

 

So with an LS1 tank, LS1 ECM and the purge valve from a GTO, you can voodoo magic the evap system into working?

 

If you are running an ls1, with the firebird/camaro ls1 ecu, then you can have the canister vent valve working correctly as its this ecu that is required.
Remember on this setup there is 2 valves, evap purge on the ls1 engine, and a charcoal can vent valve that dumps to atmosphere.

Otherwise if you are running an ls1, etc... without the 'correct' ls1 ecu (as mine is a GTO ECU) you cannot run the canister vent valve, So you can remove the ls1 tank charcoal can & vent valve, and set it up for the GTO charcoal can which doesn't use a vent valve to atmosphere.

On the ls1, the line from just behind the throttle body(if i recall correctly) goes to a evap valve(to control when fuel vapors from the charcoal can should be put into the engine), this line still runs to the charcoal can as per usual. That valve is still required but controllable from all LS1 and probably LT1 ecu's.

The tank has a mechanical over-pressure relief valve, that runs as normal and doesn't require any input. The fuel tank pressure sensor, is used on the correct ls1 camaro/firebird ecu, for all other purposes its not required. (i believe its partly used to control the vent valve)

This is how my ls1 is running full emissions for engineers etc....

Example, Looking at the picture i posted, going from the fuel sender back, the 1st line is the new vent to atmosphere where the vent valve would have been located, its not needed for the GTO can. The red line is your emissions line which runs to your engine. The 3rd line is the fuel tank vapor in.

Im not sure on the lt1, however i imagine it being ecu controlled had an evap purge solenoid on the engine, any ecu pin out diagram of the lt1 ecu would be able to confirm this.

Hope this helps. The biggest part, is to not be confused by the evap purge valve on the engine vs the vent valve on the ls1 tank.

 

Wow! Lots of info here. BUT, I still don't know if my 95 Caprice PCM can be tuned to control the 2001 plastic tank EVAP system.

Next, if it appears I can't figure out how to make the EVAP work, how do I by-pass the system or how should I modify it ?

Just so you know, I used the 95 Caprice LT1 engine and PCM.

 

LT1 has an evap valve(if its the same as below), its the vent valve on the tank that you cannot control, see my post above how to get around it.