Gen3 3sgte Sw20 Idle

[solitaire]

Hi All,

I have a weird one for you - I have not searched because the conditions of my fault are pretty hard to type into a search field.

My MR2 Project (1990 gen1 with a 1997 3sgte in it) is very nearly finished but i have one problem.

When i start the car it idles fine, about 1100 which is a bit high ill aggree but nothing im concerned about (unless you tell me i should be).

When i take it for a test drive it is fine until i hit boost... it seems the higher i boost the higher my idle goes - until its idleing at about 3000rpm. If i boost a little it idles at 2000 ish, boost a bit higher it hits 2500ish. boost heaps it idles at 3000.

The idle returned to normal when the car sat in the garage for about 3 weeks with battery disconnected. but started again as soon as i boosted as i described above.

The diagnostic mode thinks everything is absolutely fine.

anyone have any idea? i do not know where to begin...

[deaf_rattle]

vacuum leak?

[solitaire]

vacuum leak?

thats what i thought to... but the fact it resets itself over time would rule that out? (im asking... not telling)

[deaf_rattle]

vacuum leak?

thats what i thought to... but the fact it resets itself over time would rule that out? (im asking... not telling)

not necessarily, but im half drunk, its sunday just after lunch so i wont get into too much detail.

[fivebob]

Which Evap system are you using, GenII or GenIII?

[solitaire]

Which Evap system are you using, GenII or GenIII?

yikes i have no idea... i hate to say it but i have no idea what an evap system is

[fivebob]

The charcoal canister that collects fuel evopouration from the tank and connects to the plenum. Gen III uses an ECU controlled system, and I think that the Gen II just uses a one way valve.

[solitaire]

The charcoal canister that collects fuel evopouration from the tank. Gen III uses an ECU controlled system, and I think that the Gen II just uses a one way valve.

Oh, im using the canister off the gen1 body. its has a little plastic cylinder inline on the pipe that runs from the intake manifold.

Do i need to source a gen3 canister?

[fivebob]

It's not just the canister, it's the VSV that controls it as well. You should be able to use the Gen II system, but given your symptoms I'd check that the one way valve is functioning as it should.

[solitaire]

It's not just the canister, it's the VSV that controls it as well. You should be able to use the Gen II system, but given your symptoms I'd check that the one way valve is functioning as it should.

Just had a look here: http://www.mr2-tech.com/bgb/mechanical/volume1/emission_control_system.htm

And i have the jet but i dont think i have a vsv in line as it shows there... ill go and look and report back.