[WhiteSpyder]

This may, or may not be a good question. I am fishing here. I got my GT back together in February. After fixing a bunch of emissions stuff, I had to run it a bit to reset the fuel trims before I could get it smogged. It passed, and I have been driving it. Then I decided I wanted to put my cold air intake back on it. Would there be any reason to do something with the fuel trims again seeing as it flows a lot more air ? Not sure if anything should or could be done. Anybody have any imput ? ...J.D.

 

[WhiteSpyder]

I agree. Nothing to tune there. My thinking is just that being as there is more airflow the trims might need a bit of a "tweek". The computer should take care of it if I reset it. Thanks. ...J.D.

 

[WhiteSpyder]

More air to the MAF tells the ECU you need more fuel. I don't think there is going to be any BIG change, but there should be some difference in fuel trim settings. ...J.D.

 

[WhiteSpyder]

The MAF [for Mass Air Flow] measures the volume of air coming into the engine. This tells the ECU how much fuel to supply INITALLY. In the Eclipse the MAF also includes an air temp sensor which the ECU uses to calculate air density. That information is then modified by the readings coming from the O2 sensors. The O2's give the ECU "feedback" so it can correct the mixture if it needs to. ...J.D.

 

[WhiteSpyder]

The purpose of using a Cold Air Intake is just as the name implies, to route colder air to the engine. Colder air is denser allowing for more fuel to be supplied by the MAF. ...J.D.

 

[WhiteSpyder]

UPDATE: I've only run 24 miles since I restarted the fuel trims. I can tell it is changing but not enough miles yet. Cold idle has changed a bit, and it is playing around It's idle speed, but throttle responds seems to be improved already. Just bought $50 worth of fuel just now and it only got me 8.47 U.S. gallons, so I am not driving any more than I have to. I guess I'll have to wait a bit to see how much difference re-setting the trims will make. ...J.D.

 

[WhiteSpyder]

Back when I started this thread I had put my long tube intake back on and was less than impressed with how the car was running. It seemed a little "dead". I disconnected the battery so as to re-start the fuel trim process.. I have not had a much reason to drive it so it took a while to draw some conclusions. Fuel being at almost $6 a gallon right now has slowed my driving a bit too. Now I am seeing a marked improvement in throttle response. It took it a bit to readjust to the new air intake, but it takes a lot less throttle to get the job done. My conclusion is yes, I would recommend if you are putting on a cold air intake to reset the throttle trims. ...J.D.

 

[WhiteSpyder]

Sorry to drag this on more but had an interesting observation on this. I got the Spyder out yesterday. It is warm and sunny here. It was almost 90 deg, I had to go to a neighboring town to a doctor's appointment. The car has now settled down to a very even idle at about 700 rpm. The interesting part is when I first fixed the EGR problem and got it smogged it would smell very HOT under the hood after driving it a while. After re-setting the trims [50+miles later] the hot smell is now gone and the throttle response is "spot on". My THEORY is it was a bit lean after reconnecting the EGR, and adding the CAI. The re-setting the trims corrected that. Looks to me like the factory has these set up on a very thin margin mixture wise.
Just a theory mind you. ...J.D.

 

[WhiteSpyder]

Probably does not do much just to change out the air box. Just more noise. Really need to draw air in from outside the engine room. Where I live the ambient air in the summer is well over 100deg.F in the daytime almost all summer long. Under hood temps get "out of sight". Someday when I am bored I'll tape a remote digital thermometer under the hood and put the meter in the driver's compartment. Would be interesting to see just how hot it gets. The 92 octane surely cannot hurt though. ...J.D.

 

[WhiteSpyder]

I use only premium fuel. I have seen a high temp here of 117 a couple of years back. This spring I am changing to a semi-synthetic oil 20w-50. The car has 143,000+ on the clock, and runs solid. Not taking any chances with lubrication.
...J.D.

 

[WhiteSpyder]

My 3g has had a busy life. It was originally leased to a rental company in Las Vegas new. I purchased it in 2005 and it became my commuter car. I tried using lower octane fuels a couple of times. Both the car and I have been retired since 2008. I "resurrected" it this year after 4 yrs. in storage to become my plaything. I never use anything but high octane fuel anymore. Lower octane does not improve fuel mileage for this high compression engine. It just makes it run like a dog because the ECM retards the timing when it detects pinging. ...J.D.