Pete47

Hi again. Well I'm about to try a lower Octain but I was wondering if I should get a special type of fuel injector cleaner or something of that sort? Any recommendations or can I just switch fuel octain?

Mikishots

That's low. I get 169 miles average on a half tank, using Chevron 87, and I have a heavy foot. Isuppose a lot of things could account for this, but I have no idea what. Using higher octane fuel is a waste of money for any gain.

stealthscotty

Just switch, Pete. The higher octane fuels have fairly good additives included, so think of it as returning to basic fuel after an extended cleaning. It won't hurt to burn a tank of super once in a while if you feel like it.

Pete47

Stealthscotty? I change the fuel yesterday to a lower grade. I put Chevron regular 87oct and I have driven over 50 miles and the car rides the same and I don't feel no knocking. Thanks buddy for all the help.

I'll keep everyone posted on how many miles I'm getting on 87oct from a full tank. O.... I'll use rednecks_r_us method of calculating miles per gallon.

Thanks alot everyone.

gino

How much you should be getting depends 1) manual or auto tranny, 2) tire pressures,
3) state of engine tune--stock in excellent condition or modified, 4) how the car is driven.

Assuming your P5, like mine, is manual, in excellent tune without major mods, and you drive
fairly aggressively (we're not talking street racing), you should be getting 27+ to around 29+,
based on what others are showing here and what I'm getting with a 2003 P5 and a 2003 ES.

When the tank in either car is showing half-full, the odometer is reading 240-255 miles.

The ES and the P5 both have a MagnaFlow CB and an Injen CAI. Both run on 85 octane fuel at
5280+ feet--you need 87 at lower altitude. You don't need 91 octane. You're wasting money.
An engine needs an octane rating that matches its state of tune. If your timing is at the factory recommended setting, 87 octane will suffice. 110 octane aviation fuel won't make your car any quicker or faster than 87 octane.

I returned from a road trip last weekend of nearly 1700 miles, most of which was run from 85-90 mph and 400 miles was into a stiff headwind. I averaged 28.78 mpg.

BTW, check your plugs, if you haven't and replace them if they're high mileage items. Also, check that your tire pressure is around 35 psi and is even in all the donuts.

Hope this helps.

Pete47

My car is bone stock with 37090 miles. It's auto. I just recently stoped useing 91 and started to use 87 Chevron. I put my tire pressure to 32 like the manufacture states, and I just purchased my car about a month ago. My goal is to make it run at its best and very smooth with very light tunning such as intake and exaust. I would really love to get an ECU to make it run better but it seem like thats hard to find. Maybe even some better brakes and roters.
I noticed that around 1/2 a tank I was around 150 miles is this okay. You mention (GINO) around 250. Thats around 3/4 of the tank for me.
Please w/b with any suggestion or info. Thanks

Pete47

Okay I was driving today and I noticed with the 87octain that I just put in is making the engine knock very lightly is this normal or is this sound in every one elses car?
After this tank of fuel I'm going to try 93 again to see if I hear the light knock.

paulp

PETE -DRAIN THE OIL AND GET RID OF Z-MAX-THEY ARE UNDER INVESTIGATION AND THE REPORT I READ SOUNDS LIKE IT BREAKS DOWN THE OIL INSTEAD OF HELPING IT(assuming we are talking about you using the z max oil addditive)Type in z-max in GOOGLE. automatic always get less mileage.LAZLO123 and my wife both have dx.with a 5 speed I can get 30 city, 33 combo and 38 highway..and like lazlo can get 40. IT IS ALL HOW THAT RIGHT FOOT LETS THE "AIR" IN. YES AIR..you really are presssing on the aor pedal and not the gas pedal--think about it These cars are ulev-ULTRA LOW EMMISSION VEHICLES. IN OTHER WORDS -LETS REDUCE THE DRIVABILITY OF THE FUEL EFFICENT 4 CYL. AND LET THE BASTERS WHO DRIVE GAS GUZZELERS ALONE. 87 oct. is all you need .higher octane burns much slower and less efficent.IF YOU CAR DIDN'T PING BEFORE KEEP USING 91/93 AND WATCH HOW IT WILL. NOW..when your baby gets older it will become carboned up..THEN.. use higher octane to save the pistons,rod bearing etc. THE MORE ***** TO THE WALL YOU DRIVE , THE FATTER YOU WALLET MUST BE

Pete47

. like I mention I just changed gas octain and I hear a little tick now. I'll keep trying out the 87 gas and I'll let you know how my cars doing. Other than that I went on the Purilator web site and seen that we have a pcv valve to change, should I do this change this as well? Where is it? I would like to know whats the best lubes for the car do you recommend any? I'm planning on putting the higest quality oil filter I can get but I dont know which one is best other than the one you recommended. What do you think of oil types like synthetics and viscosity? I personally like to put the best material and lubricants for my car. But I would like to know whats the best stuff.

Mikishots

Lazlo, Gino's units are off...240-255 kilometers is more like it. That about 155 miles or thereabouts. 510 miles (full tank?) is 850 kilometers. Ain't gonna happen, even with Grandma pushing.

Your mileage is the same as mine, no worries.

Two things I did that really helped with fuel economy - I yanked the intake resonator and installed a K&N filter. I got 295km on my first half tank with some aggressive driving sprinkled in. I'm going to run a few tanks like this, and if I find out that the intake resonator was limiting my fuel mileage, I'm gonna be pissed.

Pete47

Did you put the square K&N filter you can get at a local Auto Zone store or did you order the intake it self and diconnected the whole air filter and airbox?

gino

Miki--

The figure I posted--240-255 miles--is just that. Miles. Both cars run anywhere from 390+ to 420 mile per tank. I've gone a tad over 420 a couple of times, but I'm running on fumes.

You mention 510 miles on a tank. Agree it won't happen. But you're doubling the figure 255 I posted for a half-tank reading. No fuel gauge I've seen is linear--as you drop past half full, the needle drops to "E" more quickly.

The figures I'm quoting are after 5000 on both the P5 and the ES. Both have Injen CIAs and MagnaFlow CBs. Both are NA and manual gear boxes.

As the man says, "Your mileage may vary." Mine does, depending on weather and how many times I stuff my foot into it--hard not to. I assume the P5 mileage will drop as some of the mods I have in the works are completed.

Gen 3s just wanna be driven. Hard.

Mikishots

Gino, you're absolutely right. My brochure (CDN) states around 7.5L per 100 km on the highway which translates to around 450 miles per 55 liters of fuel.

I have yet to burn a full tank at highway speed...amazing what kind of difference it makes. Thanks for the correction.

For Pete: the K&N was $50 CDN, and it just replaces the OEM filter. Same size, shape...just different color.

The resonator is the big black plastic muffler right near the radiator top - it keeps the intake noise down and acts as a simple moisture trap for incoming air. The problem is the intake nozzle is stuffed into nowhere! Cool air will have a tough time getting into that.

Two nuts hold it on, and a simple clip just in front of the airbox. If you take it off, put the nuts back on the studs fairly tight so you don't lose them.

gino

Miki--

Of interest, I have 278.9 showing on the reset odometer with a half tank of fuel left since filling up on the way back from that road trip.

It'll be interesting to see what the total mileage is--maybe 30+/per...

Knight

Had my 03 Pro5 for a little over a week, first tank averaged about 28 mpg with 60/40 percent highway/city driving. haven't finished my second tank yet so hopefully it stays consistent or improves as the car gets "broken in".

I agree, just enjoy the ride, but pay enough attention 'cause poor mpg can indicate probs.