Hi all Just noticed that my battery clamp was only connected on the strut side - peering down into the engine bay to see where it'd gone, I noticed this broken filter housing thing that clearly should be joining two rubber hoses, one end goes to a sensor on the engine block, the other seems to join a small black box (the size of a beer tin ish but rectangular) below the battery Whatever was in this thing is long gone, I've joined the hoses temporarily. Any idea what it is please? Thanks Andy
BTW, it's sitting on a standard til receipt for size reference, it's only small say 20-25mm dia and a bit like an inline fuel filter, the tubes at either end are narrower than a Bic biro 5-6mm
It kinda looks like the MAF sensor - check your air filter housing, take off the top and it's in the upper part of the housing. If it doesn't smell of petrol, it's not a fuel filter. I think all the fuel lines are hard on the copen. Vacuum sensor, maybe? Edit: Photo of the location? Like, where in the engine does it plug into exactly.
Dammit, you got me thinking about this more and more. It could be an inline air filter for the inlet manifold, unlikely as this looks to be on the LHS not the RHS. It could also be one of two different check valves. Given the size, it could very well be the valve that goes from the fuel tank / evap canister, or a vacuum line for the BoV
sure as all get out looks like a check valve (they only allow the air to flow one way) and fits in with the description of the fuel evap system.
Thanks gents, I think you are both right on the EVAP system - I think it's a non return valve I did a fair amount of searching and the clues point to that - if the black box under the battery is the carbon filter then it's almost certain I actually bodged the two hoses together with the only right sized tube I could find - a green rawl plug... I took it for a spin, and burger me if it didn't feel a lot quicker. I thought it must be my imagination so I did a quick 0-60 run and at it'd dropped from 14 to 12.7s I'm stunned. Better still, it's using a lot less fuel. I usually get around 200km from half a tank, I'm up to 250 on 3/8s I'll change my rawl plug for something more free flowing - but quetion is, what does the non-return valve do? I mean, is it going to cause problems not having it there? Cheers Andy
...and I forgot to ask, how/why can the EVAP system make such a huge performance difference? That is in line with the D Sport ECU I fitted
Haha, knackered? Take a look at the photo again - it was in shreds, like a cabbage leaf after a good caterpillar feast What I'm struggling with is that it made such a power difference, AFAIK EVAP is just to trap any petrol vapour intermittently, I can't see how it can affect the main supply?
That's the question. I imagine, the engine is getting more air in (or not enough), causing it to run lean (or rich). This fits with the shitty MPG The Copen should throw an ODB-II code and light the MIL, which I'm guessing it didn't. Maybe it wasn't as bad to light the MIL and go into limp home mode. The check valve has the following specs (which seem to fit): Length: 59cm Outer diameter:28cm Inner diameter: 3cm Part #: 90048-20012-000, which looks to be a Toyota part. I'm guessing it's about 20 GBP. Edit: If your coke can looking box has three hoses connected to it, it's the evap canister. Tank, purge, and atmosphere.
Thanks Nick, I presume you mean mm not cm, that one won't fit! I found a recall notice for diahatsu in Indonesia, that part looks v similar - its such a nasty cheap thing I'll be outraged if its 20 quid mind I'll have a better look at the weekend, in the meantime I'm pleased with the extra go and longer trips between filling up
Non return valve(check valve) simply lets air only flow in one direction, more common on turbo charged engines as the boost could otherwise cause problems for some of the systems. I am fairly certain the engine does not benefit from the evap system but your fuel tank and the environment do. with a missing valve it certainly would have been running the wrong air fuel mix. maybe there was enough restriction to keep it from throwing an active code but not an optimum burn. what we need to confirm is which way the check valve was working and then any old one will work if installed in the correct direction. I would wager it would be there to only allow air to go towards the throttle body (a vacuum situation).
