High adv. timing on a 04 40-50 dregees?

[Sobie]

What would cause high adv. timeing. It happens when i let off the gas. The car runs the timing around 35-40 during normal driving. Don't know what to look at or fix?

[dsmuts]

It's supposed to do that.

[Sobie]

When I put the scaner on another car 05 gt it never went over 34 degrees.

[dsmuts]

Is the 04 a gt?

[Sobie]

Yes it is a 04 gt and the car I put the scaner on was a 05 gt

[FriboRage]

This sounds normal, I see 30-40 sometimes when I let off and coast at high speed/going downhill

[Sobie]

I was thinking that that was bad. Because the car will only get 19mpg on hwy and has little power. I friend at work get 25-28mpg on hwy with there 04. I haved changed about everthing a know too get the mpgs better. Is that bad for mpgs?

[dsmuts]

High timing is good for gas mileage

[Sobie]

But to high timing could be bad an burn up the motor, and you lose some of the powerstroke then you lose power?

[Fivefingerdeathpunch]

It would help if you listed parts you have replaced.

Like what have you done, any check engine lights? What speed do you drive at?

For a NA car 35-40* adv sounds pretty normal for crusing speeds. When you let off the gas, its cutting fuel supply and will raise timing some then come straight back down once the gas is touched again. These cars can handle alot of cruise timing, many people with tuners try and get them to stay around 35-40 for S/C cars on the freeway.

[Sobie]

Sorry I did get back I have a hard time getting in too the forum.
I have replace the cat and o2 sensor, all the injectors, 10,000 on new plugs and wires, cleaned the throttle plate and change at fluid 25,000 ago and did intake and valve gaskets. The tires I run on the hard side. There are no code on the car. I did my testing at 55 on a straight road that is fairly flat.

[Sandman]

I run 35-45 when cruising on my GTP.

[Sobie]

The car is a stock na 3.8. It just seems high?

[Sandman]

50 is to much, I believe after 45 or so there's no benefit/loss in power.

[Sobie]

My 2001 gp seem too have more power then the 04 gp. I will check the 01s timing when i get it fixed. Would there be a sensor or some thing that is not just right?

[matt5112]

Its a stock car, don't worry about it.

[Sobie]

Yes it is Thanks I try not to lose any more sleep over it. lol