Poor Fuel Economy

B

baloneyhomie

Member
Hi everyone, I've had an account here since I purchased my Marauder back in January.(I'm not much of a message forum guy, I usually stick to the /r/Crownvictoria subreddit), I have a question that I feel y'all would be more qualified in helping me out with. To start, this is a 2003 Marauder that I purchased with only 35k miles, and have put about 2.5k on, it is now at 38,7xx miles. As far as aftermarket parts goes, I have not put anything on since I purchased it although it does have a Reinhart performance chip, an electric water pump, and underdrive pulleys. Now, I always get 10MPG in my town no matter how I drive it, whether or not I have the performance chip "on" or off (in my specific car the previous owner had set up a rotary dial that allows me to switch to and from the performance mode to what I assume is the stock tune, and a valet mode. The blank selections act as a kill switch of sorts, but I digress). The only time I get even above 12MPG is when some of my driving is on the highway, but I rarely ever get on a controlled access road like that. I have checked the tire pressure and all four are at the recommended PSI, I have changed the oil as of 2 days ago (not sure if that could affect it but worth listing I figure), the transmission fluid is in good shape, but I routinely get 200 miles or so out of every tank (I usually fill up when the fuel light comes on because I hate taking chances with gas, even if I'm in a pretty urban area) even if I have the performance tune selected the entire time, or the stock grandma tune selected. I really cannot think of any way that the only other thing that might affect the fuel economy (the underdrive pulleys) could affect it so much so as to bring it down to barely double digits. For context, I live in Georgia and my area is basically a pancake besides some very soft/rolling hills. It's not really stop and go hence my usage of town instead of city. If anyone has any suggestions, please put em down below. I can survive with 10 MPG since I don't drive often but if there's an anomaly on this car then I'd like to get that fixed or looked at if it's out of my area of expertise. I can provide pictures of stuff if needed, please just give me the word. Thanks.
 
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Given that the advertised fuel mileage is 17/23 (city/highway) IMO you have a DEFINITE ANOMALY. *Especially with the minimal mod's that you have.
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RubberCtyRauder said:
Get rid of the Rheinhart crap. You live in GA. See Marty Ochs, Mo's Speed Shop, Dallas, GA for a real tune.
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About an hour drive from where I live. I'll try and put some time aside to give them a visit this weekend. That being said, what's the issue with the Reinhart tune, or is it more of the fact that Mo's Speed Shop is just better?
 
baloneyhomie said:
About an hour drive from where I live. I'll try and put some time aside to give them a visit this weekend. That being said, what's the issue with the Reinhart tune, or is it more of the fact that Mo's Speed Shop is just better?
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Reinhart was known to many as a hack and a crook. I personally never dealt with him.
 
Let us know what he finds. My mileage generally suffers due to my heavy foot, but my MPG is still generally double your results.
 
I'm pretty positive it was actually the damn tune. Although the fuel gauge isn't really accurate, I've driven her enough to know that I usually get to 50 miles every quarter tank. I took off the tune (It was a weird one that connected to the serial port inside the EEC rather than programmed through the OBDII port. I forget this thing is 17 years old so the computers inside are ancient!) and topped of my tank. I've driven 20 miles already which normally the fuel gauge would be about between the 3/4 tank and full tank, but it's still on the full tank marker. I'm not totally sure, but honestly given how well taken care of this car was I couldn't find or think of any other reason why I got such *****y fuel economy. I'll try and attach an image of the chip and switch so y'all can see what I mean.
tune1.jpg
tune2.jpg

Going to get that Marty tune, methinks. The stock tune is so anemic. It appears the MPG issue was solved, from what I can tell based off the fuel gauge compared to my normal experience. Kinda pissed off I went through more fuel than I could have, but oh well. Thanks for all the help, guys.
 
Peace2Peep said:
when you get that tune...lookout! the "Partay" will begin...it's a better experience in EVERY manner!
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How difference is the fuel economy with the tune or is it basically negligible? I assume I'll lose out on maybe 1 or 2 MPG but it's a far cry from the 10 MPG I was getting with that godawful Reinhart tune.
 
baloneyhomie said:
How difference is the fuel economy with the tune or is it basically negligible? I assume I'll lose out on maybe 1 or 2 MPG but it's a far cry from the 10 MPG I was getting with that godawful Reinhart tune.
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It will go up from what you currently have.

OEM with Lidio tune = 22mpg
Add 410s = 20.5mpg (and well worth it!!)
Add Trilogy with canned Trilogy tune at 350 RWHP = 24mpg
Add Martyo dyno tune, 17* timing, 409 RWHP = 17mpg
Add my custom designed exhaust fabbed by Red at Martyo's with new dyno tune, 14* timing, 436 RWHP = 20mpg (16* timing shot it to 463 RWHP so Jeff had to dial it back as still OEM block internals)

So, ya, you can do better.

Good luck!
 
Not totally sure in your specific case, but with the 4.10's and the tune you should be even or just 1-2 loss from normal. Normal for me was 21mpg
 
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Complaining about mpg with a Marauder is silly. We all know what we were getting into when we purchased this vehicle. We made our bed, we'll sleep in it.

However... complaining about mpg with a valid reason is completely different. As GDMJOE said.. It's an anomaly.

Even with a crappy supercharger or elite amp/sound system, No Marauder should be under 17 mpg. Are the fuel lines clear? Tank empty of debris? Saw another thread (not here on this forum and not a Marauder) that some guy got a leaf or something stuck in the tank and covered the flow from the fuel pump to the engine.

Now, how likely is that on your Marauder? I would venture slim to none. But can't rule out the outliers. One thing I've learned with ownership of this car is that SHE'LL fool you. I hope you figure out your gremlin

Also yes go to Marty for all things modification.
 
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