Fuel injector change for FE...

[ar5boosted]

Originally Posted by teoman

ar5boosted, if that were the case, then then his exhaust must have been smelling of raw fuel. Or are you saying that it combusts later without providing useful work just heating the exhaust.

Less fuel is being sprayed, but the amount of fully vapourised fuel (the part that will combust and explode) is the same as the old injectors. Increasing fuel-economy.

[t vago]

Originally Posted by teoman

ar5boosted, if that were the case, then then his exhaust must have been smelling of raw fuel. Or are you saying that it combusts later without providing useful work just heating the exhaust.

It also creates soot that sticks to the exhaust insides.

[jonzobot]

I just did this mod today.

Replaced a set of 1999 single-pintle injectors in the Tercel with 12-hole injectors from a 2011 Yaris in the junkyard.

Not quite plug-and-play. I had to cut and solder the new wiring connector to the Tercel harness. At least the injectors fit in the rail without too much difficulty. Car runs just fine and no leaking fuel.

The Yaris injectors I am given to understand are ~200 cc, whereas the Tercels were 176 cc, so it will run rich until the trim knocks it down a bit.

I'm interested to see the effect on my next tank though

[t vago]

That's about a 13% increase, so your engine computer's trim should be able to adjust for it.

Very much looking forward to seeing your results, too.

[roosterk0031]

T vago do you have a 2 piece louvered grille, on side mostly open other half closed. I've been seening that car(grille) for a while years on 151, saw it Friday just just north of Amana 4way stop 5:20 ish. My eyes never get much past looking at the grille but think it might have been a magnum and maybe dark grey. Used to see a Neon? with a grille block on the road occasionly.

13% increase might also let you run E85 without a CEL.

[jonzobot]

So I drove 250km on the highway today.

This might be placebo, but my first impressions are that the engine feels a lot more smooth and quiet. All good signs - even if the fuel efficiency doesn't change at all, a smoother engine can only be good for wear and longevity.

Power did not really seem noticeably different, though my butt dyno isn't all that good.

[Baltothewolf]

Jonz expect your economy to be down this tank, because the trims will take several drive cycles to fully settle down. The only thing I would be worried about is, on cold starts when in open loop, the car will be running much more rich, and burn more fuel.

[teoman]

I believe it learns that too. It uses closed loop data to adjust the open loop behaviors.

Speaking of the cold engine ove fueling issue. Could that not be overcome? Or would the engine stall.

[roosterk0031]

I'm pretty sure the LTFT (long term fuel trim) carry over to Open loop to compensate for variations in fuel. Generally LTFT can go about 20 either way without a CEL. This is why if you put in to much ethanol you will get a CEL, even if the injectors are keeping up. With 13% larger injections your LTFT will be a negative with regular gas but probably still in the OK range.

[t vago]

Originally Posted by roosterk0031

T vago do you have a 2 piece louvered grille, on side mostly open other half closed. I've been seening that car(grille) for a while years on 151, saw it Friday just just north of Amana 4way stop 5:20 ish. My eyes never get much past looking at the grille but think it might have been a magnum and maybe dark grey. Used to see a Neon? with a grille block on the road occasionly.

Yah, my grill is half open like that, and that was about the correct time I left work. So, yah, you probably saw me.

This morning, got a current trip figure of 29.0 MPG.