98 zx2 manual trans, getting 25mpg - is that normal?

Just as the subject says, I'm only getting 25mpg. The car is rated at 33 .. I don't expect it to get that high, but isn't 25 a little low?

I replaced the air filter with a K&N filter that you never throw out, just oil every 60k miles.

On highways I drive ~70mph and use higher gears for city driving to help improve efficiency.

Any thoughts?

is that 25 highway? granted im in no position to say eitherway, my car for the longest time was getting 24-26< mine is auto, and i use cruise like its going out of style. but on long distance drives (say 200 straight) i get about 35-37 on middle grade octane... which i advocate using... it quiets the motor vibration, and i get better milage... by like 2 or 3 miles, but still.

there are also mechanical things. the fuel filter, carbonization on the valves. at work we have a fuel system cleaner... the good stuff, not that crap you buy at wal mart. using that plus the filter replaced... ive seen some cars go from 16 to 32. not bad but it depends on milage.

there is alot it could be.

Well, it's 25 all-around. I just did some math using how many miles I've driven on a full tank, both city and highway. I've never calculated it on a long stretch of several hundred miles.

Can you give me the name of the good stuff you use? Is using a cleaner like that a good alternative to getting a new fuel filter or getting the fuel injector flushed?

basically the walmart stuff (and there are alot of variations) eats away at your rubber and plastic parts, thus fouling the injectors (eventually). what we use at work is a machine... it runs through the lines and the systems. im not sure what its called. it doesnt degrade the lines or the injectors because it doesnt have time to sit in. it runs through and your done in about an hour or 2. but i could also be completely off base here. when was the last time it went through a tune up? like wires and plugs? as i said it could be alot, alot of people think that air alone will help but it takes air, fuel, and "ignition". if you have weak ignition, lack of air, lack or too much fuel in you a/f mixture. basically it all goes to hell the higher the milage (except for air because you change that more often)

So a tuneup is probably in order. If I go to a mechanic, he would run some tests to figure out what, if anything, needs replacing?

at least having a mechanic see it would be in your best interest. (being a mechanic myself, i really cant say if its one thing or another, but based on milage, and year, you can guess; because certain things have a shelf life i.e. your trans fluid... just because its a manual, doesnt mean you can drive it for 100,000 miles w/o a change) but go to where ever you trust (you dare take it to walmart i will kill you. they are on the bottom of the list.) basically the "trusting" of a garage goes like this: walmart>bad, quick lubes>inexperienced mechanics, dealer lots> good (they have dedicated mechanics that know all the tricks, of why this does this, or that does that), but good luck having them show you where on the car,and how. by far the best in my mind is a reputable garage, my boss said it best dealers are like optomotrists< they only specialize in eyes, throw a broken bone into it and they are lost. garages are like general practitioners... they know a lot about everything and have the knowhow to not only fix it, but show you, and explain what exactly something does. my trick for you though is ask to see the origional technicians document, or sit outside and watch them. you want to see the document because the guys out front might omit something and wait for it to cascade into a larger more expensive problem. techs ussually omit minor things like minorly loose ball joints (happened about a week ago but the car was still under warentee, and it was from a place renouned for fuck ups... im not defending the decision if i were the owner ild like to know that, so kinda spy on the techs. with that knowledge have them LOOK at but not touch, yet, your car. they ussally refer to it as a "drivability" exam, they test every damn thing from fluids, brakes, seals, wearing parts... e v e r y t h i n g. bring back what they tell you. and let us know and we can see if we can help.

i get 25 around town....42hw

at least having a mechanic see it would be in your best interest. (being a mechanic myself, i really cant say if its one thing or another, but based on milage, and year, you can guess; because certain things have a shelf life i.e. your trans fluid... just because its a manual, doesnt mean you can drive it for 100,000 miles w/o a change) but go to where ever you trust (you dare take it to walmart i will kill you. they are on the bottom of the list.) basically the "trusting" of a garage goes like this: walmart>bad, quick lubes>inexperienced mechanics, dealer lots> good (they have dedicated mechanics that know all the tricks, of why this does this, or that does that), but good luck having them show you where on the car,and how. by far the best in my mind is a reputable garage, my boss said it best dealers are like optomotrists< they only specialize in eyes, throw a broken bone into it and they are lost. garages are like general practitioners... they know a lot about everything and have the knowhow to not only fix it, but show you, and explain what exactly something does. my trick for you though is ask to see the origional technicians document, or sit outside and watch them. you want to see the document because the guys out front might omit something and wait for it to cascade into a larger more expensive problem. techs ussually omit minor things like minorly loose ball joints (happened about a week ago but the car was still under warentee, and it was from a place renouned for fuck ups... im not defending the decision if i were the owner ild like to know that, so kinda spy on the techs. with that knowledge have them LOOK at but not touch, yet, your car. they ussally refer to it as a "drivability" exam, they test every damn thing from fluids, brakes, seals, wearing parts... e v e r y t h i n g. bring back what they tell you. and let us know and we can see if we can help.

excellent advice, thank you .. i wont take it to a dealer because i simply don't trust them, but there is a pretty reputable mechanic nearby .. i'll pay him a visit one day

jeez altec how do you pull 42 highway? is that with all the little things you have done? or is there one thing that helped more then others?

I have a 98 ZX2, ATX, 129k, and I get on average 37mpg. That is a mix between highway and city. If it's just freeway I can get 40mpg, if i go hotrodding all over town I get as low as 25. If the mileage is all city, I usually average 34mpg. All I have done is a Keman Intake, removed exhaust resonator, and have a Ford Racing ZX2 Borla muffler. I still run Valvoline 5w30 every oil change.

5w-30? i thought that throws the vct codes. thus the switch to 5w 20.

Nope, no codes at all, runs real strong and has never given me problems. Always starts fine in cold or hot.

good driving (under 3k at all times), nice weather, Intake and a PCM from ford with a nice A/F ratio..... (ive seen stock codes do 10.5:1, cars love to do 14:1...im doing 12.8:1)

what's a PCM? can you give me the part number so i can take a look?

thanks

its the computer in the car, there are like 40 different possible pcm's you could get/have lol there is like 4 for each year, not couting amy "updates" ford released to correct for emissions change

You can look on the passenger door jam(by the hinge) for a sticker with the code (ie ngp0, xhg3, mta8, mta5)
98's tend to have one that starts with MTA...they are tuned more for a smooth ride rather then power or gas.

its the computer in the car, there are like 40 different possible pcm's you could get/have lol there is like 4 for each year, not couting amy "updates" ford released to correct for emissions change

You can look on the passenger door jam(by the hinge) for a sticker with the code (ie ngp0, xhg3, mta8, mta5)
98's tend to have one that starts with MTA...they are tuned more for a smooth ride rather then power or gas.

What's the code on yours?

What's the code on yours?


I have an S/R........the S/R PCM is in a league of its own :) Total FordRacing performance tune.

how many s/r 's were there... ild like to someday find one?

were they limited edition or something? i can't find any for sale online

according to altecs zx2 guide in progress ( its near the bottom of the page now... but personally it should be paper clipped to the top and stay there so we can glance at it... and add if needed) there were only 2000 made... which would be like the saleen mustang of the zx2's.

2000 in 2000
106 in 1999

Heh, wonder if I can find one in a ZX2 in the local junkyard...

aside from the PCM and intake, not much is worth taking

but your a 98...so you will need to do some wire work

was there any one upgrade that gave you the most noticable increase? and did you ever get that intake manifold work done?

havent tried, NGP0 is the best for power/fuel combination, XHG3 was good on gas, heared CWQ3 was. anything 2001+ is just gonna BLOW on gas, 99-00 are the best PCM years.

i have an 01, whats it take to swap the pcm? i saw a thoroughbred in a junkyard, what is different about those?

thoroughbred? a s/r pcm will pop right into a 99.5+

Yeah, it said thoroughbred opposite the ford emblem on the trunk lid. looked like an 02/03. i got a taillight off it, bout the only good thing left on it. made me wonder.

sounds like a thing a ricer put on

could be, but it looked very professional, like it came from the factory. will the s/r pcm work in an auto? i was reading on zxtuner and it said the one they sell works on all 99+ with a manual trans.

s/r pcm's dont have the ability to tell an auto trans when to shift

so, whats a good pcm for an auto? the ngpo? or is it only for manuals too?

I was geting about 25 mpg then when I changed the timing belt, I noticed the timing was way off. I assume it's from the factory because i bought the car new and it never had timing work. Anyways when I corrected it I went up to about 37 at a 50/50 mix of highway/city and the engine ran much smoother. I have a feeling that more than a few of these cars were carelessly assembled at the factory. Either that or that friction bolt on the intake sprocket slips out of wack every 100,000 miles or so but I have never got over 25 until recently.

I was geting about 25 mpg then when I changed the timing belt, I noticed the timing was way off. I assume it's from the factory because i bought the car new and it never had timing work. Anyways when I corrected it I went up to about 37 at a 50/50 mix of highway/city and the engine ran much smoother. I have a feeling that more than a few of these cars were carelessly assembled at the factory. Either that or that friction bolt on the intake sprocket slips out of wack every 100,000 miles or so but I have never got over 25 until recently.

So, wait .. you just replaced your timing belt and the efficiency went up? Do you know what the specific timing problem was?

I am assuming that stupid intake sproket was slipping. I lined up one cam, turned the other cam to make it line up. took off the belt. and gave the crank a good turn before it hit the timing peg. Reguardless the intake cam was not lined up with the crank. I never know where I'm at with that exhaust cam I just take it off take out the VCT and start from scratch, just line up that single hole at 12 oclock and hope that it still lines up once you reconnect it and rotate the engine a few times. I only had to do it 3 times before I was happy. Plus it was 95 outside. I was in a pissy mood. :banghead:

so, whats a good pcm for an auto? the ngpo? or is it only for manuals too?

the good Auto PCM's are EMA0 and JZB1....you can find them on ebay, they let the auto tranny rev out a little farther.

was there any one upgrade that gave you the most noticable increase? and did you ever get that intake manifold work done?

Going from XHG3 to NGP0 the car felt much better due to the added timing, the pully made the car feel like it was more rev happy, and pullig the knock sensor made the car just feel VERY smooth in the powerband(ad is according to my dyno)


Im working on a SVT mani swap.

i get 25 around town....42hw

I get 36/42 city/hwy as well, all I have is Zmax treatment, knockoff brand tornado fuel saver, and bosche platinum4 plugs. And a manual trans. of course.

i get 25 around town....42hw

Imagine if these cars had a wide ratio six speed like they need to cruise around at 2KRPM@60. I guarantee they could get 45 or more mpg.

Here jldude here's a Christmas Present for you!

https://www.zxtuner.com/displayProductDocument.hg?productId=214&categoryId=17