Automotive "chip"

[ptonsparky]

My grandson chipped his gas burner Dodge Dakota and wasn't impressed with the change, if any. They allow a full refund if he wasn't happy so it goes out in the mail today. High dollar unit of about $29 IIRC. I won't hold my breath over that refund.

I could not see how it did anything at all because it was hooked in parallel with the engine block temperature sensor. ??

Someone enlighten me if possible.

 

[kwired]

My grandson chipped his gas burner Dodge Dakota and wasn't impressed with the change, if any. They allow a full refund if he wasn't happy so it goes out in the mail today. High dollar unit of about $29 IIRC. I won't hold my breath over that refund.

I could not see how it did anything at all because it was hooked in parallel with the engine block temperature sensor. ??

Someone enlighten me if possible.

What kind of performance change was he looking for?

Seems like about all it would maybe do is give main control false indication of temperature and cause it to react to that temperature. Could maybe result in a change in fuel consumption - I could see this eventually leading to other problems if constantly responding to false conditions.

 

[ptonsparky]

He is 17, the vehicle has oversized tires and 8 cylinder in a small pickup. He said something about better mileage but I would guess performance would have been preferred.

IDK if they use Modbus for some of that stuff or not.

 

[kwired]

He is 17, the vehicle has oversized tires and 8 cylinder in a small pickup. He said something about better mileage but I would guess performance would have been preferred.

IDK if they use Modbus for some of that stuff or not.

I guess IDK about Modbus either. How old is the vehicle?

 

[MAC702]

I don't think that counts as "chipping" it.

What he really needs is this special sarsaparilla snake oil additive I sell.

 

[K8MHZ]

You do know that fooling with a vehicles ECM is not legal unless it is going to be used for off the road use only.

I don't think we should be giving advice on how to defeat factory computer parameters for vehicles that are going to be driven on the road.

 

[olsondavidj]

I'm not a car guy, but this sounds like snake oil to me. What exactly did he have installed?

"Traditional" chipping is tweaking parameters on the ECU. Doesn't generally involve adding new hardware. It's also a lot more expensive than $30, and might even be a custom job if the vehicle isn't factory (or if it's a newer vehicle that people don't have experience tuning).

I did some looking and maybe this what he got:

https://performancechiprevamp.com/dodge-dakota-performance-chip

Couldn't find a schematic, but looks like it's designed to intercept or bypass a signal somewhere to trick the engine in to using a different air/fuel mix WITHOUT modifying the ECU.

So maybe he installed it wrong, or got a bad product? Looks like they have options to order, so maybe he accidentally ordered for the wrong engine. Also a chance he bought a cheap knockoff somewhere and got burned.

Also FYI modern vehicles use CAN bus for communication.

 

[kwired]

You do know that fooling with a vehicles ECM is not legal unless it is going to be used for off the road use only.

I don't think we should be giving advice on how to defeat factory computer parameters for vehicles that are going to be driven on the road.

Maybe, but the main question was whether or not something connected to engine temp sensor circuit even has the ability to do such things and not a question of how can I improve my vehicle's performance?

 

[olsondavidj]

You do know that fooling with a vehicles ECM is not legal unless it is going to be used for off the road use only.

I don't think we should be giving advice on how to defeat factory computer parameters for vehicles that are going to be driven on the road.

Well we don't REALLY know that it's going to be driven on the road.

But to build on this, often chipping/tuning involves changing settings on the engine that are there for emission controls or for fuel efficiency. Well, they're not strictly for those purposes, but they were set at the factory a specific way to ensure that the vehicle meets regulations.

I mean if you think about it, any pickup manufacturer is going to do everything they can to maximize HP and MPG in order to set it apart from the competition at a given price point. They spend a lot of time tweaking the engines to maximize those parameters while still meeting regulations.

So regardless of whether this device can actually do what it says, the end result is almost certainly that it'll be violating regulations by doing it.

The other thing to think about is that the vehicle is not typically designed to handle the additional power. Every modern vehicle manufacturer, especially US ones, are squeezing every dollar they can, which means they're not building tons of overhead in to their design. So you're going to get premature wear and tear on everything. A guy I worked with a few jobs back tuned his EVO to more than double the stock HP... he threw some rods and nearly trashed the engine.

 

[K8MHZ]

Maybe, but the main question was whether or not something connected to engine temp sensor circuit even has the ability to do such things and not a question of how can I improve my vehicle's performance?

As a former ASE certified tech, I will tell you no.

 

[drcampbell]

No, it won't do anything useful.

Back in the day*, you could malcalibrate the engine-temperature sensor and fool the brain box into enriching the mixture by reporting a temperature lower than the actual temperature. But that doesn't work with modern* cars; the algorithms are more sophisticated and do more cross-checking. About all you're likely to do is induce a fault code.

For example:
Estimate the outside-air temperature by measuring the intake-manifold air temperature a few moments after starting. Compare that with the coolant temperature and oil temperature, and watch how fast they rise. If one of them doesn't rise proportionally to the other, (or doesn't rise at all) flag it as a failed sensor.

With modern closed-loop control, the exhaust-gas oxygen sensor is continuously monitored to set the mixture. If there's oxygen in the exhaust, (which would cause NOx formation) the brain box adds a little more fuel the next time. If not, (which would cause CO formation) a little less. Using this method, the air:fuel mixture is never exactly stoichiometric, but it's always really, really close.

The algorithms are capable of measuring the exhaust-gas oxygen content (and inferring the air:fuel mixture) of each cylinder with a single O₂ sensor by precisely timing just when the O₂ measurement is made. The measurement is made at the moment when the exhaust gas from the desired cylinder is flowing over the O₂ sensor. (the downstream O₂ sensor is used to validate the catalytic converter's performance)


* My apologies; I'm not sure when, exactly this happened. Late 1980s?

 

[kwired]

As a former ASE certified tech, I will tell you no.

Are you up to date on how things are done? If not you may only be as good of a technician as the latest models you were once familiar with.

If temp sensor has turned into something that connects to a common bus for many other things - it may be possible to add such performance enhancing items to that bus. I kind of doubt it is all that likely, but certainly is possible.

I can see it fooling the main controller into thinking conditions are different than they actually are and getting a predictable response - though as I said, could also lead to other problems eventually.

 

[K8MHZ]

* My apologies; I'm not sure when, exactly this happened. Late 1980s?

Actually, late 70's early 80's.

The new systems are much more complex than the first ones that controlled carburettors. One thing has never changed, and that is the fact that the computer will use the O2 sensor information to make the final 'decisions' like you said.

'Re-mapping' engine controllers really does nothing without other modifications. Re-mapping allows for performance changes in exhaust and intake to be made. Proper tuning of re-mapped controllers requires a dyno. I got to wire one of these up for motorcycles for this very reason.

I have been working on computer controlled systems since GM came out with their C3 in 1980 or so. I don't do any more 'for pay' vehicle work, but I keep up on it and buy scan tools and stuff so I can work on my own.

It used to cost a month's pay to buy a tool to read the computers of all cars on the road at the time. Now I have one that doesn't even use wires and I have less than $50 into it. With it you can read MPG to the tenth as you drive. It reads out on my tablet computer. Neat gadget.

 

[K8MHZ]

Are you up to date on how things are done? If not you may only be as good of a technician as the latest models you were once familiar with.

Actually, the newer models are easier to diagnose using a scan tool. They will locate the exact cylinder a problem is occurring on. The ones with O2 sensors for each cylinder will indicate via scan tool if the problem is ignition or fuel/air.

The one I have can also be used on diesels, from small Ford Power Strokes to 14 liter semi engines. I can do 'buzz tests' on Ford injectors with it. Thats where a signal is sent to the injectors one at a time so you can hear if they are working or not. Nice feature.

As interesting as they are, working on them still sucks. But I do my own and work for friends and family. I have too much invested in car tools to just let them sit idle.

 

[oldsparky52]

... stoichiometric ...

Nice word! I had to look it up, thanks.

 

[drcampbell]

... It used to cost a month's pay to buy a tool to read the computers ...

I used to do powertrain development at the Big 3, so I always had the most-proprietary stuff available and somebody else paid for it. A friend once asked for a scan-tool recommendation and I couldn't offer anything useful; only "We use DEVAid and CANalyzer." He called back a few says later to let me know that DEVAid wasn't available to the general public and a full CANalyzer suite was $11.000. "I didn't pay that much for the car!"

... stoichiometric ...
Nice word! I had to look it up, thanks.

I like it, even if spell-checkers tend to choke on it.

Now pronounce it! ...

There is not a consensus. Sometimes five syllables, sometimes six, often abbreviated to one, sometimes "lambda" is substituted.

 

[K8MHZ]

stoichiometric

stoichiometric

Nice word! I had to look it up, thanks.

Now pronounce it!!

I remember when it first hit the car manuals. That was the beginning of the change from being a mechanic to being an automobile technician.

 

[oldsparky52]

60's were points, plugs, condenser all got changed twice per year. Had a timing light to check/set the timing.

Many years later I got a good deal on a used 1981 Camaro Berlinetta. Tried tweaking the timing a little and blown away when no matter how far I twisted the distributor, the timing didn't change.

I started reading about this car and .... I haven't worked on one since, lol.

 

[K8MHZ]

I used to do powertrain development at the Big 3, so I always had the most-proprietary stuff available and somebody else paid for it. A friend once asked for a scan-tool recommendation and I couldn't offer anything useful; only "We use DEVAid and CANalyzer." He called back a few says later to let me know that DEVAid wasn't available to the general public and a full CANalyzer suite was $11.000. "I didn't pay that much for the car!"

And now all I need for CAN bus is a $39 adapter cable and a $40 program for my Android tablet.

Since I used to work for Chrysler, I keep an eye on the new stuff that is coming from them.

NINE speed automatic transmissions?? Wow!! 90:1 gear ratios in Jeeps using low range? Crazy!!

And in spite of what the old time mechanics predicted, all this complicated stuff is actually lasting longer than ever, instead of failing early and costing customer millions.

 

[ptonsparky]

Maybe, but the main question was whether or not something connected to engine temp sensor circuit even has the ability to do such things and not a question of how can I improve my vehicle's performance?

That is the question. I didn't work and I wasn't surprised. He may have been disappointed a bit but not much. At $29, he didn't appear to have had high hopes for anything.