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  #11  
Old 09-12-2009, 11:19 PM
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Yup thats how it is right now. 2 kids, 2 dogs, 2 cars, and a house will do that to you. A chip is out of the question. I'm not buying a chip every time I want more. Every thing I have set up is fine. I do monitor my motor very well. At this point I do not have one problem with it. I would not change it unless it made it better.

Its hard to find the info I'm looking for. ALLOT of the info I'm looking for seems to be on other forums. I just need to find or have a conversation on this subject. What reads the boost and can you do some thing about it?
 
  #12  
Old 09-13-2009, 12:19 AM
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there is nothing that reads manifold pressure inside the intake piping on a 97. the MAF reads airflow volume, thats it. the boost or vacuum acts on the diaphragm in the fuel pressure regulator increasing or decreasing fuel pressure. that combined with a rough estimate from the narrow band o2 sensor gives fairly accurate fuel injection.

the MAP sensor doesnt have any bearing on performance, its just there as a safeguard so that you dont overboost. the diode mod removes the safeguard. your car doesnt even have a MAP sensor so forget you even heard the words 'diode mod'.

you probably cant pass 14psi because YOU ARE TUNED FOR 8PSI. the car can adapt only to a point. you need to change your software fuel and timing maps if you want to change any engine parameters. if you are intimately familiar with the software you can get 20psi spikes from it, but just throwin on an MBC, like i said, is a great way to lean out and blow your engine. you need to increase fueling, and make sure you are monitoring a/f ratios all the time, if you want to force more air into the engine- which you can not do without a wideband sensor and logging ability.

finding out your engine is knocking by pulling your spark plugs and looking at them is useless. it takes a second to ruin the engine, how fast can you pull and examine your sparkplugs? 25 minutes? thats several thousand times too slow.

the reason those chips are $300 is because someone spent tens or hundreds of hours with a car on a dyno and fine tuned everything for you. all you have to do is plug it in and drive. no guessing if your a/f ratios are good. no guessing if you are dangerously lean or too advanced in timing or too hot or too rich. no possibility of destroying your car. sure you can save $200 if you DIY, but you have to know how first of all, and second- you have to have the time.

do it the right way or not at all. if you want your car to continue to not have a single problem, this is not the way to do it.
 
  #13  
Old 09-13-2009, 01:06 PM
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I understand every thing you said. So there is nothing that reads psi. The ecu reads that its to lean and just cuts the fuel? Now when raising psi thats means the fpr raises to. Dose the fpr reach its max and thats way you lean out? Whats the max psi the injectors can handles before they start spraying funky? I would never buy any bar fpr. AFPR is the way to go as you can fine tune it if need be. As for timing doesn't the ecu adjust timing on its own (to a point). It would be nice to know what that point is (-20-+20)? The ecu will adjust to a point what are these point? I under stand more then you think. Every car every ecu is different. Look at the a4s with the MAP. I have the same thing but that ecu reads it different.

Sorry but you need to read on how to read plugs if you think its useless. Reading plugs is a difficult job. They WILL tell you every thing you need to know (EVERY THING). Yes you would be a jackass to turn psi up by 10 right away. But if you turn it up by 2psi go for a run and then check the plugs. The plugs will tell you what you have to do to keep going. On that run you would find out what your EGTs would be, if your running to rich or lean if your getting knock. The plugs will tell you if you need to change the heat range for the plug. If you need to change the gap or not. Plugs will tell every thing. Do you really think I could spray a 100 shot on high comp 11.1 pistons with stock ecu with out looking at the plugs. Looking at the plugs is the only reason I was able to do that and have it reliable.
 
  #14  
Old 09-13-2009, 01:18 PM
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I don't think he was implying that you were wrong or that there isn't good info to be had by checking out the plugs, just making a point that if you bomb the motor it'll be too late. Also, you're talkin apples and oranges here. What you did with the motor in that link and what you're trying to do with this one aren't the same.
 
  #15  
Old 09-13-2009, 01:33 PM
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that mazda is entirely different, on other cars you can tune thru hardware adjustments only, this is not the case with an Audi.

the ecu doesnt add timing on its own, it only pulls timing when the knock sensors tell it to. you need to hook up a laptop with a vagcom cable if you want to advance timing and play with fuel injector settings (program called lemmiwinks by revo) to actually (roughly) tune your car. if you log the timing in vagcom you should see the ECU pulling zero to 4 degrees of timing at any point in the log. pulling more then 4 degrees or so indicates a problem.

the general rule of thumb for fuel pressure is boost+FPR=6bar or less. if you are boosting 1bar (14.5psi) then you shouldnt have more then 5 bars of fuel pressure, measured when there is zero pressure or vac to the top of the fuel pressure regulator. if you are boosting 2bar you generally shouldnt have more then 4bar of fuel pressure.
Dose the fpr reach its max and thats way you lean out?
they are only 216cc (i think) injectors, they are just about maxed out when more then doubling the boost pressure. however the stock injectors and FPR certainly can work for 20psi because there are chips available with those kinds of numbers. your problem getting past 14psi isnt the stock hardware, its the lack of software settings.

i said looking at spark plugs is useless because its as far from real-time as you can get. they cant tell you if you are 30 seconds away from danger when you are on the highway doing a WOT run. you need real time data, spark plug condition is secondary data.
 
  #16  
Old 09-13-2009, 11:32 PM
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So what is telling the ecu I'm hitting 14psi or is it the o2 reading lean and cant pull any more timing? What is the cut any way, fuel cut or spark cut? The info you have provided is info i need to know (thanks). I'm still not under standing what is telling the ecu to cut the engine down. I read you need to upgrade the fpr when you buy a chip. is this true?
 
  #17  
Old 09-13-2009, 11:58 PM
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I read you need to upgrade the fpr when you buy a chip. is this true?
not usually, the chips you need to change stuff like that for are usually when changing turbo size (like K04 or up). but when you buy a chip, they will tell you exactly what hardware you need to run to make it work. most regular chips that work on the stock turbo do not require any hardware changes.

the "cut" you are talking about probably isnt an intentional cut. its probably just the car not knowing how to run on the settings you have. it doesnt sound like its anything the ECU is doing intentionally. like if you had a big vac leak somewhere, it would cause the car to run crappy. you are just requesting the car to do something its not expecting and it starts running crappy as soon as you cross the threshold where it cant correct by itself anymore, which is around 14psi apparently. if you had the car hooked up to a computer like you should while doing these things, you would see exactly why this is happening and what is causing it.

it could also be due to the type of MBC you are running, is it a bleed-type or ball-n-spring type? the ball-n-spring MBCs have a tendency to make our little turd of a turbo even more torque-ie by opening and closing very fast. it makes for a harsh driving condition and your car might be overcompensating or confused when it sees a massive torque spike, then a massive torque drop over and over.
 
  #18  
Old 09-14-2009, 01:38 AM
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Its a ball and spring type MBC. So the ecu cant adjust any more and then causes this cut. What is this cut though or what do you think it is. Could it be at that psi the stock gap on the plugs are to large. The weird thing about it the cel never comes on. No flash nothing. I have a narrow band a/f gauge lying around. You think that would even help monitor a/f? I had it hooked up in the mazda to make sure I dont lean out when I sprayed. I rather be a lil rich then a lil lean. IDK how well they work on turboed cars and the lights are stupid.
 
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