Neptronix

Yeah so.. you know when a car runs a little rich in the morning when you start it up, producing a little more power ( esp. if you have an intake! ) .. then kind of goes into normal mode at some point?

I was wondering if you could rig a switch to the thermostat to fool the ECU into thinking it was still warming up.. so that you could switch on an extra couple horsepowers when you felt like it, and switch back to standard economy mode when ya don't.

Would this work?

mortificationrock

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Neptronix &raquo;</TD></TR><TR><TD CLASS="quote">Yeah so.. you know when a car runs a little rich in the morning when you start it up, producing a little more power ( esp. if you have an intake! ) .. then kind of goes into normal mode at some point?

I was wondering if you could rig a switch to the thermostat to fool the ECU into thinking it was still warming up.. so that you could switch on an extra couple horsepowers when you felt like it, and switch back to standard economy mode when ya don't.

Would this work?</TD></TR></TABLE>WTF??? Why would you want to do that that's just GAS being wasted ! Oh yeah and on that process since your ecu is being tricked you aint going to be able to hit M@d VtaK

Neptronix

Isn't using more gas the goal of 95% of people on here? lol.

Don't know how rich it ran, but on my car i can notice a little more torque.. on my cavalier with intake/exhaust/pulleys/ignition, it was a *big* difference.

Other ideas: two ecus with a way to switch them. but that seems like a serious pain in the *** to wire up, unless someone out there makes a 2-way harness with a switch.

It wouldn't be hard to make a little circuit board that turns off the thermostat resistance before the vtec point.

I'm sure someone's done this unless it's unsafe ( ie: motor overheats / coolant flow is messed up ).

any ideas? ..

B18C5-EH2

What kind of engine are w talking about here?

Give me the year/make/model of the car, and what engine and ECU you have - maybe we can figure this out better this way.

B18C5-EH2

Nevermind - looks like you have a D16Y8 engine.

Short answer:

Bad idea

"Why?"

Your engine has VTEC, and that VTEC is disabled until the car warms up, so if you trick the ECU into thinking you're still in warm-up mode the VTEC will not work, thus rendering the idea pointless.

There is no good way to "tune" any 1996-up OBD2 ECU. Most people get an OBD1 ECU that can be reprogrammed on a dyno to make the most power for your set-up, and that requires a jumper harness to plug in that sort of ECU because the plugs are totally different.

By that time "cheap" is at least $300.00 or more including tuning time on a dyno, and if you live in an emissions state the stock ECU will need to be reinstalled to pass smog checks.

raphael

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B18C5-EH2 &raquo;</TD></TR><TR><TD CLASS="quote">Nevermind - looks like you have a D16Y8 engine.

Short answer:

Bad idea

"Why?"

Your engine has VTEC, and that VTEC is disabled until the car warms up, so if you trick the ECU into thinking you're still in warm-up mode the VTEC will not work, thus rendering the idea pointless.

There is no good way to "tune" any 1996-up OBD2 ECU. Most people get an OBD1 ECU that can be reprogrammed on a dyno to make the most power for your set-up, and that requires a jumper harness to plug in that sort of ECU because the plugs are totally different.

By that time "cheap" is at least $300.00 or more including tuning time on a dyno, and if you live in an emissions state the stock ECU will need to be reinstalled to pass smog checks.

</TD></TR></TABLE>absolutely correct. obd2 and up ecu's arent reprogrammable to tune like obd1 ecu's. and vtec is disabled unless the oil has reach a certain temperatue and your in gear. so dont try to hit vtec in neutral

bigbadboy

if you want more fuel just get a fuel pressure regulator and up the PSI a little. i wouldnt do it but its your car do what you want. its better than your thermostat idiea

Neptronix

Hmm, okay. I guess if i switched off the therm resistor at vtec point it would seem like i'd lose power ...

This would work on a B18B swap though, right?

OR

Does someone make a switch that switches between an obd1 ECU and a stock obd2 ECU? ie: one stock obd2 for highway driving.. switch on the tuned as hell obd1 for racing, etc.

If someone hasn't built one i may just go grab a soldering iron, a couple pin layout diagrams, and some radio shack parts and go for it.

Thermostat resistor would be a little easier though haha..

Padawan

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Neptronix &raquo;</TD></TR><TR><TD CLASS="quote">This would work on a B18B swap though, right?

OR

Does someone make a switch that switches between an obd1 ECU and a stock obd2 ECU? ie: one stock obd2 for highway driving.. switch on the tuned as hell obd1 for racing, etc.

If someone hasn't built one i may just go grab a soldering iron, a couple pin layout diagrams, and some radio shack parts and go for it.

Thermostat resistor would be a little easier though haha..</TD></TR></TABLE>

No, dumping excessive fuel does not equal more power, so the idea is flawed.

A properly tuned ECU will not result in poor fuel economy, so there's no need for a switch or two ECU's. If you're after more power, do what Tom suggested and run a chipped, dyno-tuned OBD-1 ECU with a conversion harness.

electron_si

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Neptronix &raquo;</TD></TR><TR><TD CLASS="quote">Hmm, okay. I guess if i switched off the therm resistor at vtec point it would seem like i'd lose power ...

This would work on a B18B swap though, right?

OR

Does someone make a switch that switches between an obd1 ECU and a stock obd2 ECU? ie: one stock obd2 for highway driving.. switch on the tuned as hell obd1 for racing, etc.

If someone hasn't built one i may just go grab a soldering iron, a couple pin layout diagrams, and some radio shack parts and go for it.

Thermostat resistor would be a little easier though haha..</TD></TR></TABLE>

dude this is a horrible idea and a big waste of money. you need to face facts, your d series wont make power without money. Turbo or otherwise.

Even with an LS, this would be a stupid mod, you could buy a afc and tune your a/f, but you will prolly need to take fuel out to make power because it will run rich stock.

Neptronix

Hmm... okay. that doesn't explain one thing.

Why is my car quicker in the morning?
Are my sensors dirty enough to hamper performance but not trigger an CEL, and the ECU runs in some sort of 'i'm not listening to the sensors' mode?

Padawan

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Neptronix &raquo;</TD></TR><TR><TD CLASS="quote">Why is my car quicker in the morning?</TD></TR></TABLE>

It could be your imagination, or the cooler morning air, or the fact that the engine/IM is not "heat soaked", but it is not because the ECU is running excessively rich.

B18C5-EH2

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Neptronix &raquo;</TD></TR><TR><TD CLASS="quote">Hmm... okay. that doesn't explain one thing.

Why is my car quicker in the morning?</TD></TR></TABLE>

Imagination?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Are my sensors dirty enough to hamper performance but not trigger an CEL, and the ECU runs in some sort of 'i'm not listening to the sensors' mode?</TD></TR></TABLE>

No.

o2 sensors can be "lazy" enough to be slow to respond, yet not throw check engine codes. Trust me your OBD2 ECU is already pretty damn sensitive, and much more likely to throw CELs than OBD1 and pre-OBD ECUs.

The ECU goes into "limp" mode if certain codes are being thrown. "limp" mode usually dumps more fuel, but also retards ignition timing, which is NOT increasing power output at all. Ove time it fouls plugs and o2 sensors out prematurely, and it's not recommendd to run an engine long-term in "limp" mode. Some codes even trigger the engine's rev limiter to drop all the way down to 3500rpm or so if it's distributor related.

Why did you ask that question though?

venomzz

My D16 does the same thing because of my intake, exhaust, oversize injectors, runs much better on start up when its running rich and yes there is an ecu that you can buy that has removable chips to interchange race programs...june, skunk etc. as well there is a switch so you can go back to stock ecu...just found it today and I am getting ready to install it as soon as it gets here.

Neptronix

I've never heard of such a thing.
Let me know how it goes with this super sweet ecu of yours.

I'm pretty sure i'm not hallucinating about morning power. But it could be that my car warms up at 1.5krpm and i'm going that fast as soon as i let the clutch in.. ha ha.

It sounds like the multi ECU idea is go. I'll make a post if i manage to rig something up

( this is what happens when a ex-playstation modder, circuit bender, and former radio shack '1001 electronic projects' champion gets into cars.. lol )