modify the maf= bad idea

[Mystikal_1788]

i was thinking was modifying the maf a bad idea- i did and i also modded the bcs and now my car runs like shiet has anyone else had probs from doing this 2 simple mods?

 

[turboholic]

-It's a pain to get to, look like a big nut(19mm?) with 2 wires come out and go to a black connector on the intake mani bracket.

 

[Tom N]

Originally posted by Mystikal_1788
good thinking turbholic ill look now! is it hard t see nd what does it look like? behind cylinder number 2

Its really hard to see from the top. its on the back side of the block but if it went bad it would usauly trough a code. When they start to leak they just get real good ears and pull timing for any noice it hears. Your simptoms doesnt sound like just a bad knock sensor. It wouldnt be the cause of the car running real lean. It would just make the problem worse.

 

[Mystikal_1788]

ok i see the black connecter with a black with white strip and a white wire is this it?

i have no codes no lights no nothing idle is good

well tommorow im gonna wire the gauge in and tape it too the dash how ghetto? well any thing else?

 

[Tom N]

Originally posted by Mystikal_1788
well tommorow im gonna wire the gauge in and tape it too the dash how ghetto? well any thing else?

lets just start there. you know where to tap into for your vacuum line correct.

 

[Mystikal_1788]

well there is a few vaccum lines running off from the firewall well the two closest to the driver side the one on the bottom that runs to the manifold correct?

tap in there and run the vaccum line to the guage and then ground the wires

 

[turboholic]

http://gallery.consumerreview.com/car/gallery/files/gauge_hose.asp

-Follow the hose from the end of the fuel rail to the solenoid on the firewall.

 

[Tom N]

Originally posted by Mystikal_1788
well there is a few vaccum lines running off from the firewall well the two closest to the driver side the one on the bottom that runs to the manifold correct?

http://www.myzero.com/gauges/boost.html


you tap into the line from the fuel pressure regulator to the solenoid on the fire wall. just follow the link it is very clear with a pic of what solenoid to use. it shows three of them but if you DONT have a california car you will just have 2 solenoids.

 

[Mystikal_1788]

see i explained it exactly damn im good just messin- ill get it in and boosting so we will post result's tommorow stay tuned


TO BE CONTINUED.............................................

 

[LaserRST]

Dont toss the car man. Detonation happens when the car is too lean. Instead of the combustion chamber burning it explodes, causing lotsa unwanted damage to your engine. Not good. You check engine light should be on. Have you got any of your codes?

If its too lean the ECU is missing counts of air running in your car. Or its not able to deliver gas necessary to run the car right. I would check feul pressure, the ECU for its codes, and most likely the MAS because thats one of the things that was touched. This unit measures the amount of air coming in, if too much comes in and it doesnt know it will run the car lean. If its running so lean why doesnt the O2 sensor pick anything up? This may be a contributor but will usually put out a code. If you are not getting any codes than it could be something else. Check the ECU. I have a home remedy to collect ECU codes. Its cheap and EZ lemme know if you want the recipe.

 

[Mystikal_1788]

so i hooked up the pod today and guess what 9psi in all gears and 18 psi of vaccum exactly what it should be So what is next? laserrst i think you are on to somthing that is what i thought in the first place, actually that is what this thread is about - NO codes none not even a check engine light - but give me the recipe maybe there are codes and im not getting a light - so yeah the gauge told me nothing but my turbo is right where it should be- AHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
sorry i had to vent- i think that it is my god damn maf sensor- i could get one for 70 bucks should i go for it? well i ordered a air/fuel mixture gauge today and i was pissed that i didn't get my single pod so i ordered a duel pod- so laserrst thanks for the input i was leaning towards that but this thread made me think otherwise....... also 90tsiawd what is your input- i got the guage in and it runs perfect

 

[LaserRST]

What you need for the home built code reader for this car is some wire, small aligator clips, and a buzzer or a light that can handle 12v. Next to the fuse box by the drivers kick panel is a connector that is usually covered. This has about 5-6 pins in it. Connect one end to the far upper left, and the other end in the bottom opposite corner, far right on the bottom. With the key in off and it connected, turn it on to start, it should blink, if it doesnt light up or buzz try reversing the polarity. If its just consistently on than that means the ECU is fried, or your connections on the pins might be touching adjacent pins. You can have this installed while the engine is running too, turn the car on and drive with it installed if you git codes on the road and not when you turn the car on. I would try gitting another MAS and see if they will have a return policy too just incase thats not the situation, that way you dont blow 70.00. Good luck.

 

[Mystikal_1788]

well tommorow im going to order the maf sensor for 70 bucks it's used but it's worth a try im also gonna try the recipe tommorow when i can get supplies

the thing is so wierd sometimes it kinda pulls and somtimes it falls flat on it's face

 

[turboholic]

-You can use a multimeter to check your a/f ratio. http://www.myzero.com/electrical/find-o2.html

 

[Mystikal_1788]

well guys what is the next step i hooked up the guage and that told me nothing i changed the bcs- wires and plugs and so far nothing -

is the maf nex or should i wait for the pod to come in and hook up the a/f gauge what i mean i need some info here

 

[LaserRST]

I just created a MBC for $5.50 and this sucker runs HARD!! 12-14psi all the way to 6500rpm. This might help solve the erratic boost problems, but if you are running lean this is a bad idea to try this mod. If you are getting a a/f guage install it so your feul can be monitored. This is neccessary too if you plan on increasing horse power later. If this wasnt in your plans try the MAS. I can share with you the plans for the MBC but, like I said not good on a lean car. It does git rid of the erratic boost problems though. My car did that too on occasions, put me on boost probation. Now that the BCS is out of the picture I am a free man!!

 

[Mystikal_1788]

Originally posted by biddybengbeng
with only a tune up(50 bucks), boost controller(40 bucks), boost gauge(55 bucks) and "free" mods (ten bucks) an AWD with a capable driver can easily be in the 13's. free mods are simple, but effective. remove, or hack the hell out of the 1st gen stock airbox. take off the mas and remove the air silencer. rewire your fuel pump with bigger wire (8 bucks for wire, 3 bucks for a relay). there's a few other free mods that are easy and effective; i wouldn't recommend removing the lower honeycomb as some might recommend. if you do remove it, SAVE IT SOMEWHERE SAFE. when i take mine out, i run crazy lean, and get TONS of knock. the second i put it back in, it's all fixed. NGK BPR7ES spark plugs are a good idea (12 bucks for a set of 4) and new plug wires are never a bad idea (60 bucks). www.dawesdevices.com has a super duty boost controller for 38.50 shipped to your front door. i've run 17 psi on mine with no problems at all... no spikes, no worries.

i would also highly recommend going to www.digitaltuning.com and ordering a pocket logger setup. it is by far THE most valuable thing i have purchased for my car. the great thing about DSM's is that a comperable datalogger for another type of car will run you a LOT of money, but for 150 bucks you can have one

ok so if you look at this - he says as soon as he takes the lower honeycomb out he runs mad lean and then he puts it back in and everything is all dandy again huh i wish mine was that simple-i wanna get some seriuos horses out of this thig but i don't wanna try on a car running lean- i don't want to throw in any more variables- as soon as me and you figure out the lean prb. im hitting you up for the mbc

also can i buy somthing to minipulate the fuel going in so i can just manually fix it by dailing in what i want

 

[turboholic]

http://www.roadraceengineering.com/newafc.htm

 

[Mystikal_1788]

oh yeah that is way too complicated for me !

90tsiawd hey dude i see that you are on- i got th guage hooked up and 9psi all theway around and 18psi of vaccum i have no idea what to tell ya but we are all good there

 

[Tom N]

Originally posted by Mystikal_1788
90tsiawd hey dude i see that you are on- i got th guage hooked up and 9psi all theway around and 18psi of vaccum i have no idea what to tell ya but we are all good there

Ok, we might have a fuel problem how old is the fuel filter and how many miles on the car. i assume you r using to stock fuel pump. Oh just to be sure you r holding 9psi of boost all the way to redline correct and you hooked up just like in the link i sent you.

 

[Mystikal_1788]

yes the thing is dead on 9psi ihooked it up all correct made sure no leaks and help 9psi dead on- ok you may have a point about fuel- my car gets the worst gas mileage in the entire world i know trucks that get better gas mileage-stock fuel pump- the fuel filter may very very very well be clogged i seriously have the worst gas mileage in the world -109,000 on the car and i have no idea how long the filter has been in there? like i said stock pump- but the guage held 9psi on the dot to the redline

also the first week i got it i accidently put 87 octane in and plugged one injector- so i changed the injector's out and the fuel rail- so i know those are good

when that injector whent out i threw a check engine code

 

[Tom N]

87 octain wont plug a injector. 87 octain just wont burn as slow as 93 octain. You could use 87 in your car stock i just dont recomend it. Where did you get the fuel rail and injectors from. I would get a new fuel filter on there and make sure to get one from mitsubishi. The discount part stores seem to not seal right.

 

[Mystikal_1788]

well ill get on that tonight - also somtimes when i start it, it idle's as 500rpms and is a little rough- then it finally smooths out? any thing else wrong? tommorow i will go ahead and get a fuel filter and change and also i will change the maf- one other thing i was kinda in a hurry to gat around a car today and downshifted to 3rd to get better pull- now i was expecting it to bog and it DIDN't it had the power and pull it should- but that was short lived

 

[Tom N]

Do you still have the stock cat on the car. Put the fuel filter on first then drive around and see what happens if nothing then try the maf.

 

[Mystikal_1788]

k well i didn't get on that today but it's on my list for tommorow

 

[rsk_wannabe]

This has been a very interesting string. Can't wait to see how it turns out.

I am having similar problems and would like to see if anyone can answer a question or two or fifty... hehehe.

First the background. Newly rebuilt engine (Wiseco, Eagle, ARP, etc etc) that is missing about 3" of vacuum. (15-16hg vice 18-19hg). I have tried to find the leak, but was not able to build up enough pressure with the hand bicycle pump or the cheapo cigarette lighter powered tire pump. That is the first thing wrong. I have set the timing and had adjusted the idle. For some reason it stays at 1100 for a long while before coming down to 800-900 range. I have not yet checked compression, but will do so as soon as I can.

The mods: 16g (ported not clipped); HKS UIC, Dejon Tool Lower ICP and modded SMIC (2.5" inlet and outlet); I am running the fully gutted MAF without the trap door with an old style AFC; ported O2 and turbo housing; 2.5" mandrel turbo back exhaust.

Boost gauge; A/F guage; EGT gauge; I am running stock boost solenoid since I want to learn how to tune this at stock boost levels first. I have an Apexi AVC-D, but it is not yet hooked up.

I also have RC 550s and an upgrade fuel pump (190lph , I think). No AFPR nor a fuel pressure gauge. I do have a logger. I too have the white colored NGKs.

Yesterday, I hit 1000 miles on the rebuild and tried for the first time to go WOT. Car took a dump. Felt like I hit fuel cut, but the car did not regain itself. ECU threw out a code 44 (coil) and so I swapped out the coil with a spare and everything was as it was before (running but not ideally). I am now paranoid to hit WOT. My logging efforts (to and from work 50 miles one way) show that timing is advanced alot at 3000+ rpm. Knock count is 0 almost all the way through except "very infrequent" occasions when I see 1s, 2s or 3s count. I am rarely hitting 4000 rpm for fear that the car will again take a dump (and I am all out of coils When I do hit 4000rpm, the knock count is still "0", but when after I decelerate and just rev at neutral or 1st or 2d, the knock sensor goes through the roof. WTF?

Settings were -4, -2, 4, 6, and "who cares" since I will never hit 8000 rpm. . I know these are conservative, but I wanted to start at "0" and then start moving + or - as the advance or knock dictated. I am not sure how to attack this.

Update: This evening, I moved up the 800 rpm and 3000 rpm settings to "0" and +2, respectively. Going WOT at 3rd from about 2Krpm to about 5500rpm seems fine, but trying anything close to WOT while in 1st and 2nd has me falling on my face. This really sucks for a FWD car that used to squeal those gears and chirp 3rd. There is no boost in the first two gears. WHY oh WHY?!?

Questions:
1. Is the low afc setting supposed to be full + as suggested by Quadcylla at +40? If so, does that not increase your idle tremendously. Will you not be puffing out gas plume fumes? Or was that only if you did not have upgraded FP and injectors?
2. Any ideas why the coil went KAPUT after that one WOT run?
3. With 550s and an upgraded fuel pump, isn't there more than enough fuel to compensate for the gutted MAF? BTW, I am using the gutted MAF since I used to experience fuel cut on cool nights before the recent rebuild. What settings do you recommend I start at first?
4. Why can't I boost in 1st and 2nd gears?

Sorry for the long post. But I too am getting frustrated and would appreciate any help and advice, except those who would suggest to give it to someone who knows what they are doing.... and you know who you are. ;-)

Thanks in advance.