Mod

[ryan255]

I have an 2004 GMC Envoy with 4.2L engine, and I buy a mod:

 

This mod will modify my stock ECU with a Timing Advance Resistor. This resistor connects to the car's ECU by replacing the Intake Airflow Temperature (IAT) Sensor. When the resistor is installed the ECU will read that the air coming in through the intake is cold air. In other words, this will modify the air/fuel mixture, producing more power and advancing timing 1 to 2 degrees.

 

The instructions are:

 

1.Locate the IAT Sensor, has to wires connected to it.

 

2. Unplug the IAT Sensor from the wiring harness.

 

3. Take each lead of the resistor and put it into each lead of the wiring harness plug. Put it tape.

 

My questions are:

 

1. I locate the IAT Sensor, but I cannot unplug the wires connected to the IAT Sensor. How I unplug that?

 

2. The mod will damage my engine or something?

 

3. Can I use the mod everyday?

[blue2kzr2]

I wouldn't bother with that mod. All it does is trick the ECM into thinking there's cooler air coming in so it'll dump more gas in the engine. You'll get less MPG from the whole deal...

[MrQuadrasteer]

And probably not pass inspection, foul your plugs and O2 sensors, leave your exhaust pipe black...

 

Lemme guess- you bought this on eBay for $25 ?? Guarantees 15 or more hp ?!!?

[Mighty HD]

lmao....25hp for $15 dosent make sense when we are paying $600+ for a tuned PCm that gives us 50+hp..

[100R1]

I would not do this mod if it was my 2004 trailblazer (or any newer vehicle OBDII controlled)

 

you are going to hack into your wiring harness at the MAF to get to the IAT. what will this do to your warranty if you have any problems ?

 

You have O2 sensors pre & after cats, this will make the mod less efective than on the older OBDI vehicles. Plus you will molre than likely start to throw codes.

 

I built several IAT sensor mod boxes based on SpeedTweekes design for older (pre 1996) Jeep 4.0 engines. on these engines it was effective. parts were resistor, reistat, dual position switch, plastic box, and wire. cost from radio shack about $ 4.00 total

 

Since the IAT sensor on a 4.0 Jeep engine is on the intake manifold and only has a 2 wire plug I found matching male & female plugs to hook up my SpeedTweekes IAT adjustable mod. No hacking and easy to pull if I ever needed to go to the dealer (never had to)

 

The with the adjustable IAT mod you could trick the Computer to think that the outside ambient air temperature was much colder than it actually was and the computer would enrichen the fuel mixture and add timing advance.

 

on the 4.0 jeep motor they were put on a dyno and the power increase was 10 - 12 HP to the rear wheels.

 

The best way to decribe the performance gain is that it felt like you were running in the winter time even though it was summer time (well at least for us in florida) less humidity and less heat your vehicle picks up a little more power.

 

This was on a OBDI (pre 1996) engine current engines running OBDII will not see the same increase.

 

Not worth the time , effort and risk.

 

Invest into a Tuned PCM you will not be sorry going this route. Look in the Full size Forum there are post about low cost custom tuned PCM's.

[ryan255]

Guys,

 

You are telling me (in other words), to put the mod to my 2004 Envoy or not?

[ryan255]

I'm thinking to put a Turbonator to my 2004 Envoy, 4.2L,

 

what do you think?

[MrQuadrasteer]

You are kidding, right ?!!?

 

Both of those items are junk- don't waste your money.

[asilverblazer]

Please stop shopping for the sake of your car. If you want to spend money on worthless crap please make checks payable to Andrew Doug...

 

No don't put this stuff on your truck. And avoid EBAY at all costs.

[USA1Fan]

And avoid EBAY at all costs. 

 

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Hey! EBAY is a good site to get deals on the stuff you want. Just make sure you go there looking for specific things and don't get taken in by some of the stuff you'll run into. I got good prices on both my steps and my tonneau through EBAY.

[MrQuadrasteer]

Yeah, I 2nd USA's comment. eBay kicks butt, BUT you have to do your research, and avoid the too-good-to-be-true bs that folks sell on there.

 

Like $25 chips, bs air-flow devices, eletric superchargers and the like.

 

I've made off like a bandit with stuff I've gotten off eBay

 

 

Ryan, if you'd like to pm me, I'd be happy to talk to you off-line about decent ways to improve your performance and economy without wasting your money.

 

W/out a doubt, a custom tune is your best bang-for-the-buck mod you can do.

 

Trust me, amongst all the members here, I doubt there's anything that hasn't been tried yet, so listen to those with experience

[asilverblazer]

I meant HE should avoid EBAY, I love it!

[USA1Fan]

I meant HE should avoid EBAY, I love it!

 

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okay. whydinchasaysointhefirstplace..

[MrQuadrasteer]

I meant HE should avoid EBAY, I love it!

 

<{POST_SNAPBACK}>

 

 

okay. whydinchasaysointhefirstplace..

 

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Gotchya

[jamashke]

Highjack......

 

Turbonator? So GM puts on a filter right before the MAF to "smooth" out the air. So why introduce turbulance to the air flow? Although GM does a good job of that with the OEM air tube. Oh well. Just give me some good ole beans and watch my mpg's go up by 50%.