8 replies to this topic

[BlackT5]

When I installed Nira about 5 years ago, I had to decide what to do with things like the air pump, feeding the dash the correct signal for the tach, ECT and what to do with the EVAP system. People I talked to said just disconnect it or vent it open. I chose to simply disconnect it.

My understanding of the system probably isn't the greatest, but I believe evaporated fuel gets trapped in the charcoal canister and the vapors are sent through a purge valve into the intake maifold to be burned by the engine. Since i've just disconnected the purge valve and hose to the intake manifold, i'd like to get some idea of what is happening to the fuel vapors.

I have never had any problems but I do get a fuel smell near the rear passenger wheel when the tank is quite full. As a preventative measure, I never really fill my tank all the way.

Well, gas was super cheap yesterday so I decided to fill the tank. This morning when I went into the garage, the smell of fuel was quite strong. I took the car out and ran some errands, but when I got home and began to pull into the garage, I noticed some black oily substance on the garage floor close to where my rear passenger tire normally sits.

I haven't had time to take a good look at the canister (mine is at the rear, some of them are up front) because i've been feeling like shit today but i'm just wondering what other people running standalone engine management have done with their EVAP systems? I suppose I could reconnect the purge valve and use Nira to trigger it, or even see if the stock 4.4 will do it since it's getting most of the signals from the engine in order to feed the dash.

Here are a few pics I took several years ago for reference.

[fischmama]

I ran MS3 for a while with all the lines hooked up as normal but the valve was not triggered by anything. I have had no issues with abnormal fuel smell or leaking fuel/moisture.

I just pulled the canister and vent to atmosphere right now. I still have to see if that's the correct way to go about. Not many people have messed with the EVAP system. I probably wouldn't have but mine was located in the front and it was ugly to look at. The PO ruined the bracket for it too.

I'm going to start driving car again next week. Got the Holset on finally with the stock engine since the R motor is getting rebuilt. I can report back then.

[mdlimy]

on my 850 i just removed the charcoal canister completly and left the line running under the car but cut it right near the fire wall, never had any issues, as you know i gutted as much of that usless emission crap as possible, the wonders of standalone =]
for reference, i never topped the tank off, always just let it click the gas pump off.

[850wagonT5]

There was either a recall or TSB that involved fuel vapors escaping from the tank when full. A bad seal somewhere. Your issue may not be related to your modifications at all...

[Johann]

There was either a recall or TSB that involved fuel vapors escaping from the tank when full. A bad seal somewhere. Your issue may not be related to your modifications at all...

Yep. Could be. Had the same with my first 850 (SD1).

[lookforjoe]

I'm going to use a piggy back ME4.4 ECU to run EVAP, AC, dash, etc.

The problem I have is disabling all the emissions devices will prevent me passing state inspection via OBDII.

Since you have a stock ECU running some functions, you could rewire the EVAP to restore it's normal operation, or just open the system like Robbie, so it cannot build pressure.

If the TSB was relevant to 850's, it is highly unlikely it was still applicable to '98 x70.

[550]

Supposedly all of my emissions stuff is disabled with TT, and I no longer get codes for anything ... soo I'm not sure. I had to have Adam screw with it a little bit so I would stop getting CEL's. All has been well for 1.5 or more years.

[lookforjoe]

Sorry for the threadjack....

Supposedly all of my emissions stuff is disabled with TT, and I no longer get codes for anything ... soo I'm not sure. I had to have Adam screw with it a little bit so I would stop getting CEL's. All has been well for 1.5 or more years.

Mine (TT) is as well - but.... if you check the car with the Volvo tool, all the codes are still there, just no CEL comes up. I don't get a CEL for the rear 02, but since I cut the harness, I get codes for no heater signal or output when checked with the Volvo tool. Pretty sure that will be a problem when inspecting, but maybe I can run a test & see for sure. Certainly readiness will never take place.

[550]

My point being, I'm not sure if my evap type stuff is actually functioning properly. I wonder if some of those things are even working properly, if the ECU doesn't think they are an issue, or possibly does think they are an issue.

Get my drift?

So in a round about way, I'm agreeing that it may not be linked to the EMS necessarily.

Edited by 550, 09 July 2012 - 04:24 AM.