New DSM owner.. Major problems with gas mileage

[TAndrus]

Hello everyone.

I'm proud to say I just purchased a '95 Eagle Talon TSi AWD. I don't know too much about the car besides the following:

• HKS blow off valve
• Cold air intake system (brand unknown)
• Coil over lowering kit (lowered 1.5")
• Strut tower brace
• 18" Chrome Motegi wheels
• Aftermarket exhaust (brand unknown)
• Whiteface gauges

Im new to driving a manual so I haven't really tried too much with it, but when I floor it, I get up to 16psi on my boost gauge. I really know nothing else about this car. It's got about 119,000 miles on it and the "intercooler gasket" was replaced 1000 miles ago supposedly.

I have found a few issues though that I'd like to ask about. I've found I'm only getting 12mpg which seems EXTREMELY low to what I should be getting. What could be causing this?

Also, I need to buy new headlamps but I can't really find any nice aftermarket ones. Where could I look to find some?

Thanks a ton. I hope to be a long term member of the board and stay active around here.

-Taylor

 

[TAndrus]

Okay. So far I've gathered that I should do the following:

• Boost test
• Replace the spark plugs with these
• Replace the wire set with these
• Recirculate my HKS blow off valve with this

Should I check the o2 sensors also? I don't really have a lot of time on my hands right now so would any local shops do this stuff or is it more of a do-it-at-home type thing?

 

[DSMunknown]

I don't really have a lot of time on my hands right now so would any local shops do this stuff or is it more of a do-it-at-home type thing?

If you have a brain, you will be able to do these simple processes. It's just maintenance.

If you really need help, find a local knowledgable DSMer who is willing to lend you a hand.

 

[TAndrus]

When I got my first DSM, it was getting about 12mpg also. I did all of the tests: boost leak, compression, etc. and they all came up good. Then I searched for "bad mileage" and a post came up about checking base timing. Come to find out, my cams were one tooth off causing my rough idle, low boost, and terrible gas mileage. I read the vfaq.com about timing belts, tackled the job the first time in 10hrs and the second time in 2 hours (messed up oil pump sprocket).

Check your timing, make friends with the search button here, and read through the vfaq.com

Hope things turn out good!

-Jeremy

I looked up the faq on the timing belts and it looks like a hard, complicated process. I'm totally inexperienced so I would be afraid I'd mess something up and I don't have another car I can really drive while I work on my talon.

 

[TAndrus]

If you have a brain, you will be able to do these simple processes. It's just maintenance.

If you really need help, find a local knowledgable DSMer who is willing to lend you a hand.

I suppose you're right. The swapping of the spark plugs/wires shouldn't be hard and as long as I can find the parts for the boost leak test it shouldn't be hard either. Another member mentioned a timing belt check earlier, which was what I was referring to as being difficult. I should have been more specific, sorry about that.

 

[InfiniteGSX]

Welcome! Vatozone sells a really nice little tool for like 5 bucks, it has a socket on one end and a handle in the shape of a T... Get the right size for your plugs and this will make changing plugs very easy. Also change your wires.

Remember one thing, don't touch Iridium Plugs. Very dangerous plug for any sort of forced induction. Those plugs you chose, are perfect!

Something you could try... octane booster or some sort of fuel system cleaner. I doubt that would cause fuel mileage issues tho. It would be more of a studdering or low fuel pressure if you had a clogged fuel system. But its just a thought. I noticed everytime I fill up with Chevron 91, my car runs like crap and burns the fuel very fast. I use Shell or Phillips 91 Octane. I seem to get good gas mileage on those gases... Could be all in my head tho...

 

[silvermitsu10]

Honestly. If you aren't confident in doing something like this you shouldn't even think of attempting it when it comes to the timing belt. Even the slightest mistake could mean an engine rebuild is in your near future. I'd leave that to a pro. but the rest of the stuff is pretty straightfoward.

 

[bjw24]

Get that thing recirculated.. even if it doesn't account for all of your problems it's definitely part of the problem. Good luck

 

[cbrue122]

Yes, I would recommend a new o2 sensor. After 100,000 miles an o2 sensor starts to lose its ability to accurately monitor the AFR due to age and contamination with unburnt fuel, etc. This leads to the engine running richer in closed loop operation than it would with a new sensor. This will help your mileage, however, it will not fully correct the current 12 mpg. Good luck.

 

[TAndrus]

Alright... So it looks like I'll be ordering those spark plugs and wires and hopefully I can do the boost leak test. Also I'll grab one of those recirculation things.

Any suggestions for an o2 sensor? I'll also take a look at my intake filter and see if it's really dirty.

 

[TAndrus]

Welcome! Vatozone sells a really nice little tool for like 5 bucks, it has a socket on one end and a handle in the shape of a T... Get the right size for your plugs and this will make changing plugs very easy. Also change your wires.

Remember one thing, don't touch Iridium Plugs. Very dangerous plug for any sort of forced induction. Those plugs you chose, are perfect!

Something you could try... octane booster or some sort of fuel system cleaner. I doubt that would cause fuel mileage issues tho. It would be more of a studdering or low fuel pressure if you had a clogged fuel system. But its just a thought. I noticed everytime I fill up with Chevron 91, my car runs like crap and burns the fuel very fast. I use Shell or Phillips 91 Octane. I seem to get good gas mileage on those gases... Could be all in my head tho...

What are the Iridium plugs? And when you talk about a fuel system cleaner, are you talking about something you just pour in with your gas that you can buy at like walmart or something? You said something about bogging, and I've noticed bogging when I'm running at low RPM's around 1,500RPM-2,000RPM.

 

[cbrue122]

As for an o2 sensor, I used the Bosch oem replacement unit and it has been working nicely. It was also a very slick install as it hooks directly into the factory plug; no DIY wiring. The oem unit from a Mitsubishi dealer would also work well, but either way it will cost you around $100-120 for the new sensor. If you decide to do this the front sensor is the one to replace as that is the one the ECU uses for closed loop operation.

Iridium plugs are just spark plugs with an iridium electrode. I am actually running NGK iridium plugs in my DSM right now and they have been working well for me. Not trying to change your mind; your plug choice will work excellent as well.

 

[DSMunknown]

What are the Iridium plugs?

Don't worry yourself over effin' iridium plugs. Just purchase the plugs in the link I provided for you. They are proven and effective.

And when you talk about a fuel system cleaner, are you talking about something you just pour in with your gas that you can buy at like walmart or something?

Do not get any octane booster. It's a waste of money. Just pick up some Sea Foam at your local NAPA store. Read through this long thread about Sea Foam and the proper procedure when using it on the engine.

 

[Turbo Talon DL]

Your car should get around 29-31 mpg on the freeway and maybe half of that to two thirds of these figures in the city. I noticed your recirc. tube from your UICP was attached to your air intake BEHIND the MAS while the BOV is vented. You're blowing charged air back into your air intake. Pick up a manual and some basic hand tools in order to change plugs and what not. It is very simple if you just follow what the book says. It tells you how to check the timing also. How do you run your car at 1500-2000 rpm? My car wont do anything much under 2300.

 

[cbrue122]

That is true; Turbo Talon DL is right. Once you get all of your kinks worked out and have a proper running engine it should make around 30 mpg. I usually get around 31-35 mpg while cruising highway/interstate.

 

[TAndrus]

Your car should get around 29-31 mpg on the freeway and maybe half of that to two thirds of these figures in the city. I noticed your recirc. tube from your UICP was attached to your air intake BEHIND the MAS while the BOV is vented. You're blowing charged air back into your air intake. Pick up a manual and some basic hand tools in order to change plugs and what not. It is very simple if you just follow what the book says. It tells you how to check the timing also. How do you run your car at 1500-2000 rpm? My car wont do anything much under 2300.

I don't know what all the acronyms mean. Sorry. But is it bad that the blow off is just going back to the intake?

 

[kairles]

UICP= upper intercooler pipe(I think)
MAS=Mass Air Flow Sensor(AKA MAF)
BOV= Blow Off Valve

if you look at the "1" pic you can see the hose going from just under the bov to just behind the MAS. So some of the air is blown into to the turbo inlet.

 

[BoostFrenzy]

if you look at the "1" pic you can see the hose going from just under the bov to just behind the MAS.

I just noticed that too. To me it looks like your dump tube isn't connected to anything on the blow off valve side. Is it? If it's not, that's bad.

 

[TAndrus]

Where is the dump tube located?

 

[MountainDew]

I noticed you're in Manhattan. If you're ever up in Johnson County (Olathe/Overland Park) I could take a look at the car for you.

 

[DSMunknown]

I don't know what all the acronyms mean. Sorry. But is it bad that the blow off is just going back to the intake?

Click here for a list of DSM acronyms.

No, it's a very, very, very good thing when the BOV is recirculating back into the intake. Alas, yours is not recirculated. Yet.

I just noticed that too. To me it looks like your dump tube isn't connected to anything on the blow off valve side. Is it? If it's not, that's bad.

His dump tube is capped off at the end. Look closer.

Where is the dump tube located?

It is the rubber hose right here (another angle can be seen here of the black rubber hose, with the picture provided by you). You need to purchase the adapter for the HKS SSQV in the link that I gave you in post #9. Please get some local help. Fast. I'm not joking.

 

[dsmulla]

MAS- mass airflow sensor...........it is located inbetween the air filter and the intake pipe which connects to your turbo.
BOV- Blow Off Valve...................thats the HKS BOV you have that everone is telling you to recirculate.
UICP- Upper Intercooler Pipe......that is the pipe where the BOV is attached and it connects to the throttle body and the intake manifold.

Yes, you are suppose to recirculate the BOV back into the intake pipe. That way the ECU will see the right readings and send the right signals for you car to run right.

I have had many bad experieces with O2 sensors and YES it did hurt my gas mileage. So take a look at it and see if it needs to be replaced and go from there. The front O2 sensor is the one you should be concerned about. It is located right after your turbo where the exhaust starts to exit the engine bay (O2 housing is what we call it). If you are facing the engine bay look directly after the turbo towards right hand side in front of the motor. You will see the O2 sensor sticking out and you also will be able to trace a the harness which connects to another harness on the left side of the head (motor). You can see what I mean in your PIC#5. You can see a wire loom going across the heat shield which is directly above your turbo.

Also change your plugs with the ones suggested above. There is a black cover right above your valve cover (valve cover is where it says DOHC 2000). You will find 5 phillips screws that attach the black cover to the valve cover. Once you take that off you will see the SPARK PLUG WIRES going into each cylinder (4 cylinders). Just gently pull on each wire and they will come out easily from each cylinder. Inside each cylinder where took out each wire from are SPARK PLUGS. You will need to purchase that socket that is mentioned above to take each one out. They will just screw out. You will require that socket, a rachet and an extension. Just screw them out one by one and swap them out with new ones. Make sure you gap the plugs properly. You can also by a tool from almost any autoparts store thats helps you gap the plugs. You need to gap them to 0.28. Its like a thin ruler like thing that gets thicker from one end to another. You need to insert that at the bottom of each new spark plug and gap them to 0.28. Once you get the tool you will understand what I mean. Swap each plug with the new ones and you are good to go. If you are buying new wires this will a good time to swap the new wires. This part should be straight forward. Each wire goes from one cylinder to the ignition coils. You can trace back the old wires and you will see what I mean.

Conduct a boost leak: http://www.vfaq.com/index-main.html
Got to intake and scroll all the way down to the 6th last item on the list and click on that link. INTAKE TESTER. Just follow and make a tester. Then you will attach this tester to your turbo inlet. The air intake pipe which starts of with your air filter, your MAF and then goes to your turbo inlter. Take the pipe of the inlet, attach the tester. Now I am not sure if you have boost gauge inside the car yet. I am asking that there is no way you can tell how much air you are pumping into the turbo system. Mix soapy water together an spray on throttler body, intake manifold, intercooler pipes (all of them upper and lower), BOV and aroundthe turbo. See if you can see any leaks or even hear them.

I hope this helps and if you need anymore help just go ahead and PM me and I can assist you. I went through the same stage (we all did at some point) about 14 months ago. Now I have an almost complete toolbox and have become the grease monkey of the neigbourhood. Goodluck with everything and like I said if you need anymore help let me know! Also use this page to your advantage. It will help you get familiar with your engine bay. Welcome to DSM's my friend!!

http://members.shaw.ca/costall/1000Q/
There is another link which I am trying to find but no luck. It has a virtual engine bay where you can click on stuff and it tells you a desciption. Maybe someone else can chime in.

Osman

 

[BoostFrenzy]

http://members.shaw.ca/dsm.1000q/Engineprimer/2G/index.htm

That is what he (^) was talking about I think.

 

[dsmulla]

Yeah thats exactly the one, thanks BoostFrenzy!

 

[BoostFrenzy]

No problem dsmulla. I have that little tidbit bookmarked .

His dump tube is capped off at the end. Look closer.

I see it now. Kind of hard to see. Thanks for pointing it out to me.

 

[TAndrus]

Alright..

So I opened up the hood today and took a look at stuff. I'm going to buy some new spark plugs this weekend and I'm going to run some seafoam into my vac hose to clean out that stuff. I might run some through the gas too. I looked at the spark plug wires and they look relatively new and since I'm a little short on money right now I'm going to hold off on getting new ones.

Then the issue with the blow off valve I'm still unsure of what I need to do. I'll buy that little $12 dollar part, but once I get that, what do I do? I was also given the stock little gadget that was there before the HKS valve was installed. I could use that if needed, but if I'm ordering the $12 fix, I'll stick with the HKS.

A few more questions I've got that I thought about today. For some reason my first gear is kinda difficult to push the shifter into.. Is that normal? Also, is it possible to get 15psi boost off the stock turbo that's installed because that's what my boost gauge reads at times, but my friend seems to think that's impossible.