ONLY 13 MPGS any ideas?

[rhaigh08]

2002 Intrigue 3.5L just had the transmission rebuilt then it blew again then the valvebody and solenoids were replaced it blew again so it was overhauled again and the wire harness had been crushed so it was replaced. Finally the transmission is running okay, so far but I've only put on 700 miles. Since this last time it was rebuilt I've only been getting roughly 13 mpg. I also just had the brakes done but those need to be redone because my rotors are shot and are spotted with black heat burns in them. The brakes are screeching when backing out of the driveway or turning without my foot on the brakes my guess is thats because they were very cheap. Other than that they are fine. I checked the calipers and those seem fine as well they are all expanding and contracting as they should. But I dont know why I'm getting such bad MPGS. No engine codes, I dont feel a misfire, I have 1 small hole in my muffler, Catalytic converter is new, o2 sensors are new,air injection system is new, I need new tires soon but they are all aired properly. I cant think of anything else that could cause bad MPGS. The fuel filter had been changed before I got the car and I've only put 10k on it since. It seems I notice this gas usage more right after fueling. Can the recent Transmission rebuilds cause bad mileage until it breaks in more? any ideas are appreciated this is getting costly.

[panzer dragoon]

recheck the tranny fluid level (when warm). Look into the owners manual for the procedure.

Brake in those brakes some. I air out to 40psi in the tires now. Check for your parking brake grabbing also.

[cougar214]

I'm having gas issues with mine also...It's a 98 Intrique with the 3800 series 2 in it....I gave the car a tune up and now its using more gas...WTF!....i changed the plugs,wires,fuel filter,oil filter,tranny filter,new tranny fluid,engine oil,flushed the cooling system out.The car purs like a kitten now but its using more gas and I dont know why....Could my o2 sensors need to be cleaned?.....i checked the maf sensor but its not dirty...I had an issue with the electrical system and it threw a code for the tranny shift sensors? or torque converter lock up sensor?....something like that...i know it was code p0741....but that went away when i fixed the battery problerm.it does shift kinda funny....shifts in every gear around 2000 rpm's.....when im going 40 its at 1800 rpms but at 45 its at 1200 rpms?.....doesnt sound right but ok...lol.....any ideas guys?

[dtownfb]

You didn't mention if the spark plugs had been replaced? Also are you sure the transmission is using all the gears? What is the rpm at 60 mph? I would get those brakes looked at like krivasauto suggests. you shouldn't have black marks on the rotors or hear screeching.

[cougar214]

My rpm's at 60 are 2k and yes i did say in my post i changed the plugs.my brakes do need to be done but they are not bad..Just getting to the point where the pads needs to be changed out also if it makes a difference i have 4 wheel disc brakes.I have also seen in other posts users are getting some very good results in using seafoam in their trannies and using a shift kit.I would like to think its something small causing my excessive fuel consumption but i am not a delusional person so im gonna go with the more expensive tranny probability.when i did the tranny fluid and filter change there wasnt any metal shavings in the pan which is a good thing but there was a far amount of gray sludge in the pan.the tranny seems to be shifting the same way it was before servicing it and hasnt gotten any worse which im guessing is also a good thing.but never the less it is still shifting kinda funny.i have almost zero experiance when it comes to transmissions so all the simplest answers and tips would be great.and if you can think of anything else besides the tranny that would be fantastic for my wallet....lol....thanx again guys.

[panzer dragoon]

I can run 70mph+ at 2k rpm. A good touring tire aired out 35-40 psi helps some.

auto trannies are simple = change the fluid and filter, make sure the tranny cooler works. Old fluid breaks down and causes torque converter slippage.

The parking brake is separate from the disk brake in the rear. =follow the manual linkage cable.

http://lucasoil.hodgsoncorp.com/slip...ansmission.htm

[rhaigh08]

The plugs are newer. Dont remember exactly how old they are. I put a bottle of Lucas in with the gas and it seems to have done the trick. As far as the brakes go the squeeking is slowing up so they just needed to be broken in. I'm running about 1800 RPMS at 60 mph. Now I have a new question. I can feel the transmission shift at about 10-15 and again at 25-30mph. So my guess is in and out of 2nd gear. The transmission is in the process of breaking in from a recent rebuild. But I have 2 Intrigues and I cant feel the 1999 shifting as much as my 2002 in or out of 2nd gear. I am wondering if that is normal. It doesnt feel like a slip or a hard upshift and it's not violently shifting. But it is more noticable than any other gear. So im trying to figure out if I'm over reacting or if it needs to go back to the shop.

[rhaigh08]

Cougar214 to me it almost sounds like for peace of mind you should take your car for a good drive maybe an hour or so. Letting the tranny get hot and take it to a shop and have them check the tranny for codes. I wouldnt turn the engine off until they plug it in. The problem I had with mine the first few times is when I shut the car off the codes for the tranny would often clear themselves until it got hot again.

[rhaigh08]

I didnt really have any real symptoms for my transmission acting up. accept my shift points were off and I could feel the shifting in all gears not violently but they were there. Took car to shop had all solenoids replaced. It was fine for 95 days then it started shifting violently. Took it to a different reputable local transmission specialist they ended up replacing the Torque Converter, Filter,EPC Solenoid, TCC Solenoid, 4th clutch Hub, Torrington bearing, Parking Gear Bearing, another Torrington Bearing, Banner kit, Channel Plate Sleeve, Sonnax AFL Valve kit, and a Torque Signal Valve. Then after a first failed rebuild they rebuilt it again and then it failed again and the rebuilt it again, and then found the wire harness was crushed so they replaced that this last time.

[cougar214]

Wow.Did you come to an Automotive Forum to give English lessons?I'm not being rude but I was looking for an answer to my car troubles.I didn't come here to reminisce over high school.Don't forget this is,after all,the internet.Avid internet users know how to read even when things are typed up really fast and mistakes are made.We still get the point.

Now,If you have anything to offer regarding my post I would love to hear about it.If not then please grade my paper and move along.Thank you for taking the time to teach me the proper way to write.I almost forgot.

P:S Do I get at least a B+ this time?

[LittleHoov]

Your tires are the correct size right?

Also assuming you are calculating your mileage using miles driven/gallons filled not just by going off the gauge?

Those are the only things I can think of that haven't been covered already.

As for the grammar issue, I agree that its much easier to read and process information if its laid out in a way that makes it easy to read, as opposed to a solid mass of text.

If you wrote a paper with just a solid mass of text, most teachers would count off. Yes this is "just the Internet", but that doesn't mean we have to turn into a bunch of pre-pubescent teens texting their BFF's. We're all intelligent adults here, I think we can take the time to at least communicate like them.

Go around typing giant masses of text on any forum and you'll have someone point it out. It's not just here.

End of rant.

[cougar214]

No.My intake gaskets aren't leaking.The engine purs like a kitten.I checked the maf sensor and it appears to be clean.There is however some carbon built up inside the throttle body.I'm not sure if this would be enough to cause the troubles.

[cougar214]

My tires are 225x75x16".I believe.I know they are 16's.They are a little low on air but they do however call for 30lbs and they now have 32lbs in them.I was told 35 psi was good for them though.

And yes I have been calculating my miles per gallon.i was getting around 22-24 mpg when I first bought the car.I am now getting around 18-20.

These are of course ballpark figures as driving habits never stay the same.I did take my maf sensor and throttle position sensors off and cleaned them the best I could without TB cleaner.

It does seem to have improved performance so I will go ahead and get some TB cleaner and do the job right.

[LittleHoov]

Well, factory tire size is 225/60/16. If your tires really are the size you stated its no wonder your mileage is terrible but Im thinking you are mistaken, those tires would be nearly 3 inches taller than stock, I dont think they would even fit, those are almost the same size tires I have on my Jeep! haha.

Also, have you considered doing a compression test? Might be a pain on the 3.5, but if youre really convinced something is wrong it cant hurt.


Another thing is what sort of gas do they have where you live? I know I lost a couple mpg on average when Missouri passed legislation requiring all gasoline 91 or lower to contain 10% ethanol. Something to think about.

[cougar214]

Yes your correct.They are 225/60/16.

I live in North Carolina and they also add 10% Ethanol.

I haven't really considered doing a compression test because the engine does run very well.

My only concern is for the way she shifts.To give you a better idea of what I'm saying I'll give you an example.

When I start driving the car and it takes off in first gear,I'm tranny dumb so I assume it starts out in first gear,the tack will shoot up to 2500 rpms and the rpms will go down to 2k once it shifts to the next gear.

When it shifts to the next gear the tack will raise to about 2100,shift,and drop back to 2k.Then when it shifts into I'm assuming 3rd gear the tack will drop to 1500 rpms and thats where I get the bucking back and fourth.

As my speed starts to raise to 40 mph the tack will also increase steadily to 2000 rpms.When it finally goes into 4th gear the tack will drop to 1500 rpms and the bucking stops.The tack will not increase to 2000rpms again till I reach a speed over 65 mph.

Now here is what I find strange.At 45 mph my tack reads 1500 rpms.But at 40 mph my tack reads 1900 rpms.Shouldn't your tack read less rpms at a slower speed?

This is where I believe I may have a soleniod problem or at the very least a soleniod switch problem.I could be wrong but I don't believe the rpm's should be hovering around 2k for every gear till I reach fourth gear.

I can make the rpms drop and the tranny shift a little smoother if i let off the pedal just a little till it shifts and then press the pedal back down again.