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modify the maf= bad idea

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Mystikal_1788

20+ Year Contributor
258
0
Aug 31, 2002
northfieldmn
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?
 
Explain once more how it falls flat. Any noises or change in engine sound? Just no boost? What does your boost guage measure? Sorry its been a while, bout a week, need some refreshing. We can git through this.
 
My plugs are white, which i see means its running lean. if i rewire my fuel pump, will that fix the problem?
 
took me awhile to read the many pages of this thread and i myself have the same problems with my 2g TSI..... everything was fine excellent condition tune up everything you can think of. so since i had already taken care of all the small tune ups and thing i thought it would be nice to try some basic mods and i did 2 of them.... i cut the dump tube to a respectable lenth and took out my air box and replaced it with a cone K&N filter with an adapter...... ever since then i get the same symptoms through 2nd 3rd 4th and 5th i go and gun it and it runs like a stock civic with no pull at all... my turbo spools up and i get boost fine.. the only thing i can think of is the sound of a hiss when i gun it comes from the bov section of my engine i was thinking my stock plastic bov just went to crap and cant hold over 7 to 8 psi cuz thats wat it feels im running at.... im still working on the problem as well :(
 
well my gauge reads 9psi all the way around there is no change in sound nothing- i have noticed that the belt on the air conditioning is fuuccked turned over and everytime i hit the gas i get the squeel like the belt is loose- could this be a problem- sorry it's been so long for me to write- but comp has been down- write asap- i think this belt has somthing to do with my current prob.- the belt is shredded and upside down- it is not the timing belt or the alternator belt it's the air conditioning belt
 
matt i have pmed you back- i would like to know what you have tried and what kind of results you have had
 
Ok I finally got done reading all seven pages of this thred, and would like to give you some input......I think you are headed in the right direction with the mas, the other thing I might do if I were you is hook in a multimeter into the 02 sensor ckt just to check if the sensor is switching correctly. If i remember right there is a wire for this purpose in the pass kick panel.....Note that this would only be temporary until you installed the a/f gauge.....it's late and i may just be rambling but, but what is your fuel pressure?

one thought, I'm fairly new to dsm's but turn wrenches for a living on gm products...do these things run an intake air temp sensor?

Hope I can stir some other ideas from everyone else
 
Sorry if someone already mentioned this, but I'm in a rush and don't have time to read...anyway

Did you reset your ECU? Properly? So that it can adjust to the new air/fuel mixture?

You probablly did, but maybe reset it again then see...It'll run like #@%#@%#@%#@% for a while as it begins to learn the new settings but after a few days it should run strong again, the ecu does take a while to set.
 
alright, thank you everyone for your posts and suggestions- im tired of this god damn piece or #@%#@%#@%#@%ing #@%#@%#@%#@%- i also put in my air/fuel guage today and it reads exactly what it is suppose too- lean at idel bounces when cruising and rich when wot- i just don't get it - i changed the belt -and still nothing , im pritty sure now that my o2 sensor is running correctly because im getting good readings out of my air/fuel gauge- i honestly have no idea what my fuel pressure is. i think it's good - matt and i are compiling a list of what we have tried and what we think- i hope i solve this soon or the car is going down the road. and im gonna start over. now that i know that im not running lean or rich- i think im gonna get a manual boost controller and turn it up to 15 psi to see if maybe that will solve the falling on it's face- or to see if it is still gonna bog with more psi-
 
and also sense im not running lean or rich im also wondering if the maf is ok - because if it was all wacky then i would run really really lean or rich so im thinking my maf is ok now, am i correct?
 
well it turns out im wrong- as soon as i gun it from a dead stop it goes to rich and then as i go through 1st to 2nd it starts to drop to lean and then it doesn't even read on the guage- but on the other hand cruising normally and then punching it, it stays rich ?
i have no idea
 
it did it to me on the way to work today too i punched it to go around a car and rich for a second and then fell all the way too lean and then didn't even read on the guage- so what is the next thing to try- and what is a code 44
 
should i just unplug it or what? what do you mean take it off- sorry, and thank you for your reply you have been very helpful
 
k i read your last post and i see that you have a gutted maf- and such- do you think that i should change out the coil? and could my coil just be weak and not fully gone- im just frustrated and not very good at this stuff- this is the first car i have really put some time into and effort and it is taking a dump on me- im not throwing a code- but on start up very rarely i will and it idels at like 500 and when i rev it to bring it back up to 900rpms it has a really deep growl sound like a bog and it slowly revs
and the light go's out - the other time i threw a code- was i just passed someone at wot and when i let off the gas to let it come down it came on til i hit the gas again- and the light went out
 
Okay, since it seems you are about at the end of your rope, here is my very jaded advice. As background, I have had this car for about five years. I enjoyed it for probably a total of two years. For the other three years the car has been down for every imaginable reason including broken stud bolts which broke in the head, broken timing belt which ruined 8 valves, excess blowby caused by a detonated piston precipitating one rebuild (done by me) which lasted 300 miles and caused 4 detonated pistons. Now, finally, on the second rebuild, the car is working fine. Except that now I think one of the carrier bolts broke in the block, not to mention I have a snapped exhaust manifold stud in the head. Its deja vu all over again. LOL...

My advice is to sell the car since it will give you nothing but pain and misery. If it wasn't for the fact that I am an obstinate prick, I should have sold this car years ago. Now although it does have some power even without the boost controller, it is only enjoyable when going above the speed limit. The ride sucks and is too stiff. The car rattles and you are never quite sure what will go next. I am being 100% truthful here. Unless you want to fixing the car every weekend and give up any semblance of normalcy in your life.... get rid of it.

If that is not an option, then the next suggestion is to bring it back to stock. If you have put in the bigger catback exhaust and put in some gauges fine. But once you get to the bigger turbo, bigger injectors, fuel control, MBC/EBC, bigger fuel pump, etc...then you are just asking for trouble. If you must mod, then put in as many gauges as you want (fuel pressure, oil pressure, mechanical boost, AF, EGT, etc etc). Buy a logger. Learn everything about the car first. How it supposed to run as the engineers who designed it intended it to run.

Don't worry about timeslips. If your car is faster than someone else's, who cares? Guaranteed that your stock configured car will be more reliable than any car that is modified for speed.

Just enjoy the car which pumps out about 200hp and has the added advantage of AWD (in most cases). You are already quicker than 1/2 the stock cars out there. Give it proper maintenance and you should enjoy it for a long time. As an older car, you will even save on insurance.

In short, go back to almost stock! Heck, even lowering the stance will give you headaches. Replace the coil (go to the trader for a used one unless you have a couple of $100 for a new one), return the MAF to its original condition, verify that the car is in tip top shape in stock form (compression, timing, etc....) and ENJOY the CAR!

I case people think I am being hypocritical, the fact that I stick with the car is partly stubborness and partly because I have too much invested and just want to get my money's worth at this point. Last, I drive 100 miles to work and do not want to put too many miles on my other car.
 
WOW, that was the most harsh thing i have ever read- ok well i have put some thought into it, and the car is still running and i really don't have anything invested- i was thinking of just driving it into the ground and living with it's current condition- this way i could save up some money to put down on another car that i could store in the shop and mod to my liking - this FfUuCkKIGNNdNGdgfd Piece of shdhfisdit is driving me insane so i give up- unless anyone has any idea's that will fix it!!!!!! i don't care about modding it all to hell anymore i just want the power i should have
 
If this post covers issues already addressed please just ignore it, I just wanted to give you my quick idea and did not have the time to browse the all post (I started but it became a bad nigthmare after 3 pages!). Anyway, if you're still using the BCS and it looses power in 3rd, 4th anf 5th gear you could have actually closed the bcs when removing the reducer (you mentioned having troubles with it) so you don't blead any pressure back into the intake thus causing the wastegate to open early, as you mentioned in the very early stages of this saga. Please don't bother cussing at me if somebody already suggested, just trying to help.

Leo

P.S. I would test the BCS, supplying it with 12V and verifying it opens or closes, I do not remember now, plus check if the signal from the ECU gets there OK.
 
i changed the bcs and no luck, but thanks for your reply it was much appreciated- if you have anymore idea's please please post- i would also like to kow about the coil- could my coil go weak from over gapped plugs- but still be able to run the car- because i hear if the coil goes bad the car won't start- i was thinking maybe my coil is just weak
 
ok i have decided to do something about this car because if i ever wanted to get rid of it- im sure it will be worth my time and effort to fix-
ok here is my options
1.the power transistor
2.the ignition coil
3. the maf
4. the injector's

so they are in the order that i think is most likely it- starting from one
please give me your opinion and that is were im gonna start-
 
Sounds like the same plan I had. I guess it is because you think there is a fuel delivery or spark problem that causes the bogging. I can not really help you with pinpointing the problem, but after reading over the string and seeing your first diagnosis of when the problem started, it seems that you should be able to just reverse the steps to get back to where you started fairly simply.

You stated that you already tried to swap out the BCS, but I am not sure if you mentioned that you put back the honeycomb in the MAS. Until you have tried to do both of those at the same time, then you may be spinning your wheels. Figuratively speaking.

I realize that it should not matter much with those two minor mods, but each car is different. So give it a shot.

Also, the gasket thing you found while sifting through the engine belongs to the EGR valve which is located just below and attached to the throttle body. If you are missing it, there may be some leakage there. The EGR has two vacuum hoses attached to it. You may wish to check all of your hoses too for possible tears/leaks.

Finally, try looking at your ECU and see if there are any leaky caps. Perhaps this common problem may be causing your bogging issues.

Good luck.
 
I broke down the head this last weekend, checked my valves to see if this was my problem from bogging. And everything looked good, to my amazement. So i replaced the headgasket, and looked at the EGR, cleaned it up. I also replaced the Throttle postion sensor too, thinking this would help! Took it out!!! ANd the piece of crape still does it! To top it off, I shred my tire from my wheel bearing being bad (this is a whole other store, that i don't wanna talk about though, basicly i had to go to "SATAN" to have the bearring changed. While i was there i paid them the extra stinking 75 bucks too look at the car and see what was possiable wrong! Not having anyfaith in Satan, the where actually pretty cool! They pulled my turbo off, because they said i wasn't getting proper air pressure, I asked how this was because I was getting ok read outs on my boost gauge. They thought at first it was a bad, gasket on the turbo. Instead it was a bearing in turbo was bad, causing oil not to travel threw properly. I thought the were just messing my stuff up, when they where poking at it. Though they provide me wrong, this is where i was amazed by satan, they put another turbo on my car?!?!?! An let me drive it to show it was my turbo that has been FU@ked the whole time! Oh it felt so good to drive it and feal the pull!!!!!!!!!!!!!!!!!!!!!!!!!! Changing my mind about my car, unfortunly they took the turbo back and put my crape back on, they offered it to me for 1230. and some change, i told them they where out of there mind for a stock Turbo. They told me they understood.
So i know where this leaves me, build more horsepower once again. MIS, I don't know if this is you problem, though pull your turbo off or at least check the shaft play and see what its like. I understand your problem, though i've only been dealing with it for the last month not thinking it was my turbo.
-Matt
 
huh maybe i could of #@%#@%#@%#@%ed the turbo i mean it has 111,000 on it and it is still the original-so maybe ill try to pull it off and take a look i mean it's worth a shot can anyone give me instructions on how to take one of these things off- and also thanks matt for your help- my satan has ffuucckked me twice now so i have no faith in my satan- can anyone give me instructions on how to take the turbo out
 
the honeycomb and the bcs are both back in the car and nothing so im thinking else where now- and my air/fuel ratio is good 95 % of the time
 
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