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MPG Loss...

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Posted by: Dark_Majesty_06

I have done a search.. but only turned up old post.. nothing that helped... I was getting great mpg about 2 weeks ago.. even in the stop and go of city and stuff.. I was getting 20.2.. after I changed my plugs and put a new paper air filter in.. i'm only getting.. ONLY ... 17 mpg.. I was doing really good for awhile.. on the highway.. used to.. I would get mid 20's.. even driving home.. cuz its all straight and flat.. I was getting low 20's.. what could cause this..? I have a new fuel filter.. but could my o2 sensors be bad.. or what? I'm not getting a sulfer smell or anything... what could cause a horrible drop like this.. I understand.. when i gun it.. it will drop.. but i'm hardly gunning it anymore.. afraid of loosing more mpg... and hurting my tranny...

Posted by: Battery

How many miles are on the car? Have you ever replaced the O2s before? How is it idling?

Posted by: Sal329

Bad tank of gas? Try a fuel cleaner and see if that helps.

Posted by: Dark_Majesty_06

Oh man brother.. its at 203k and climbing rapidly because I drive alot.. and oh man.. have I tried... 2 weeks owning the car.. 2 cans of seafoam.. tank and crank.. multiple fuel cleaners.. just to make sure... I'm assuming the o2's have never been changed in thier life.. so that could be the problem.. idle.. good idle.. only 2 times.. in the whole ownership of my car.. has it idled up.. to 1k.. down to 5 hundred and died.. only 2 times.. it does hesitate on take off sometimes.. only when its completely cold.. IAC or TPS?

Posted by: unity

Are you using premium fuel?

What did you gap the plugs to?

Posted by: Dark_Majesty_06

gap is set to .048.. exept for one.. which is the front passanger side.. I couldnt get it out.. I forgot to gap.. so I went back and pulled all of them.. by the time I got to the last one.. I was mad.. and it wasn't commin out.. so I just left it.. but the pre gap setting is .045.. does it make a diffrence that I went to .048 or is it because that one isn't gapped right.

Yes.. Premium fuel!!

Posted by: mespock

Don't worry about the miles except that the miles may mean it's time to replace parts like the 02s. Also don't run anymore fuel system cleaners... Looks like You've done that enough.

Posted by: Battery

It hesitates on take off sometimes? Ever replaced the fuel pump?

Posted by: unity

Spark plugs are usually not "pre-gapped". When I buy them they are gapped all over the place....

But which park plug you get?

Posted by: Dark_Majesty_06

I got the Ap24.. I wanted app724.. but at the moment.. money was tight.. still is.. well true.. some are pre gaped.. others are just poohed on... no more fuel cleaners.. I'm afraid anymore.. and i'm gunna clean my car to death.. lol.

No fuel pump change.. fuel filter is sitting around waiting on a nice sunny day after work when my house isn't flooded... I'm hoping once I get a radio.. and front bags... then i'll get a walbro.. or something along those lines...

Posted by: Battery

I've only used motorcraft copper spark plugs and they work great. My guy got them for me for a little over a buck a piece.

Posted by: unity

Ya, those Motocraft AutoLite 764 are pretty much the best you can get, and the cheapest. Anything else will diminish performance and economy.

5th grade physics, copper is the best high heat conductor. Silver or gold would be great but never hold up. Platinum, iridium, etc.. those all conduct less.

Posted by: Dark_Majesty_06

Yeah.. I'm going to pull'em out today.. and make sure thier all gapped correctly.. Now since I don't have the app series.. do they still need to be gapped at .048? Also.. I know this is totally off my own subject.. but do I really have to have a special tool to remove my fuel filter?

Posted by: mespock

Quote:

Originally Posted by Dark_Majesty_06

Also.. I know this is totally off my own subject.. but do I really have to have a special tool to remove my fuel filter?

Yes you will need the tool, but they are not expensive should be less than $20 at any auto parts store. Fuel filter is easy but sometimes they like to be a bit of a PITA, at least the top fitting.

Posted by: Dark_Majesty_06

dag nab it.. I always have to wait for this crud.. lol.. okay.. well then fuel filter will be this weekend.. after that.. I guess next big project is fuel pump..

Posted by: mespock

Ah the fuel pump. Make sure you have the tank almost empty to make it easier.

Also it is not a real PITA but at times can be. JD Auto Parts is a great place for a good 255 pump...

Posted by: 98CobraStarLSC

what i see a lot of the times is when you replace plugs that have been in the engine for a long time, the cylinders carbon track the the spark of the old plug. when the new one is installed, it will fire completely different. it usually take a couple of tanks of gas to get a new carbon track in the cylinders. don't worry. you should notice the car doesnt start quite as easy as it did with the old plugs unless they were misfiring. Just FYI, give it a few tanks.

Posted by: Dark_Majesty_06

Okay thanks a whole lot cobrastar! I sure appreciate that information.. I will give it a few tanks and see if everything gets back to normal!!

Posted by: unity

Quote:

Originally Posted by 98CobraStarLSC

what i see a lot of the times is when you replace plugs that have been in the engine for a long time, the cylinders carbon track the the spark of the old plug. when the new one is installed, it will fire completely different. it usually take a couple of tanks of gas to get a new carbon track in the cylinders. don't worry. you should notice the car doesnt start quite as easy as it did with the old plugs unless they were misfiring. Just FYI, give it a few tanks.

I can say I have never heard of that in a modern engine. Whenever I replaced plugs that were bad the vehicle immediately ran smoother.

Can you imagine all the people that would be taking cars back to dealers or tune-up shops if this was at all common?

Posted by: Battery

Yea I've never had that issue and I've change plugs for a handful of people with these cars.

Posted by: stang99x

4x4 mags have done several articles about how they lost mpg after a routine tune up. If you don't neglect it in the first place you'll be fine. The copper plugs are the best you can get, 5th grade physics and all. You can get a cheap fuel line remover made of plastic for about 5 bucks. They work about 3 or 4 times before they are shot. Run a real intake fuel system cleaner before changing the plugs, not seafoam. Then see how she runs.

Posted by: unity

Ya know, I wonder is something broke after moving all those parts around to get to the plug covers.

A vacuum leak could also cause these issues. Everything from a cracked line to a bad seal of the intake tube to the throttle body.

Posted by: mespock

Quote:

Originally Posted by unity

Ya know, I wonder is something broke after moving all those parts around to get to the plug covers.

A vacuum leak could also cause these issues. Everything from a cracked line to a bad seal of the intake tube to the throttle body.

Vacuum good thought. I just changed cracked vacuum lines my daughters car.

Posted by: Dark_Majesty_06

If its not stinking raining today after work.. I'll check my Air Intake to TB seal.. and i'll check all the surrounding vac lines.. I did a reset yesterday on my MPG.. and it was being stupid.. it was registering like.. 29.6... I don't think my car is getting that.. well.. it went down to 18-19 after I hit 125... Totally off topic here.. sorry.. but our cars aren't meant for high speed are they? My car felt like I was floating.. I was all over the road...

Posted by: unity

Quote:

Originally Posted by Dark_Majesty_06

If its not stinking raining today after work.. I'll check my Air Intake to TB seal.. and i'll check all the surrounding vac lines.. I did a reset yesterday on my MPG.. and it was being stupid.. it was registering like.. 29.6... I don't think my car is getting that.. well.. it went down to 18-19 after I hit 125... Totally off topic here.. sorry.. but our cars aren't meant for high speed are they? My car felt like I was floating.. I was all over the road...

In my eco-tune from Torrie I get 30 to 32 MPG. In performance at 65 I get 27 or 28 MPG. 29.6 is possible thanks to the locking TC the trans has.

As for floating, it is air-ride which helps a lot. Do you have it lowered? Is the air-ride working correctly?

Posted by: Dark_Majesty_06

Ok well then i'm not complain then... lol. As for air.. yea.. as far as I know its working.. it lowers after 55.. and no its not lowered yet... I dunno.. lastly.. one last off topic question... what all is required for changing front brake pads..? Do I have to take it to ta dealership.. or can I do it myself.. ? What all is exatly needed to do the job? any special steps I can't do myself?

Posted by: mespock

Quote:

Originally Posted by Dark_Majesty_06

Ok well then i'm not complain then... lol. As for air.. yea.. as far as I know its working.. it lowers after 55.. and no its not lowered yet... I dunno.. lastly.. one last off topic question... what all is required for changing front brake pads..? Do I have to take it to ta dealership.. or can I do it myself.. ? What all is exatly needed to do the job? any special steps I can't do myself?

Front Brakes easy job.. Do them yourself... Just don't tighten the caliper bolts too much they'll break..

Posted by: mespock

Quote:

Originally Posted by Dark_Majesty_06

Front Brakes easy job.. Do them yourself... Just don't tighten the caliper bolts too much they'll break.. Not

Posted by: mespock

Quote:

Originally Posted by Dark_Majesty_06

Front Brakes easy job.. Do them yourself... Just don't tighten the caliper bolts too much they'll break.. Not that I've ever done that

Posted by: unity

ECHO!!!!!

:P

Yes, front brakes are easy as Rich has pointed out often. LOL

As for floating, remember that is a Lincoln. If you want the feel of a tighter ride I suggest doing the sensor lowering or getting a module where you can adjust the height on the fly. It certainly helps!

Posted by: Dark_Majesty_06

10-4!! I figured as much.. but people were mentioning a pressure bleed on other topics.. but those were rears too... Okay.. well thanks so much.. ya.. sensor lower.. as soon as I get my front bags from rich.. cuz at 125.. floating like that.. is quite scary... to say the least.

Posted by: unity

Unless I have new tires, I never try to push those speeds. 100 max for me!

Posted by: chickenviii

no wonder rich has 10k posts!!!!!

Posted by: Dark_Majesty_06

Lol.. I know i keep asking off topic questions.. but I just want to ask in here.. so I don't take up room out there.. I'm feeling a big surge of power at about 3 1/2 k.. I mean.. putting me back in my seat.. but it feels like its kicking it at 3 1/2 k... I mean.. no missin or nothing like that on the low end.. its still pretty good on low end.. but its kind of gotten a little worse since i bought it.. maybe.. fuel filter? Plug wires? Fuel pump? Thats the only thing I can think of that would make my car... jump.. so to say... at that rpm.. any suggestions? also.. on the brakes.. anything I need to be aware of before doing?

Posted by: unity

The "kick" is the IMRCs opening to provide more high end power.

Posted by: Dark_Majesty_06

oh okay.. I guess since my car is running right now.. I feel that kick now.. thats great.. never felt it before last night.. I like that feeling!! Lol.. I want that feelings through my whole rpm range...

Posted by: mespock

Quote:

Originally Posted by chickenviii

no wonder rich has 10k posts!!!!!

You are just jelous.

Posted by: Dark_Majesty_06

Well... I offically tested mpg yesterday in town.. and i'm back up to around 18.7-9ish in town.. with my heavy foot.. so it might get around 20 in town.. it really helped changing those plugs.. now I can't wait to get 9mm wires.. change fuel filter.. and get that pesky third cat off.. free up even more exhaust flow.. and i should be doing good on mpg!!