Power loss, timing pull, please help!!

[eurofvr]

Hey guys, I am having a little problem with my car that I purchased a couple months ago. Its been acting kinda funny ever since, pulling harder with low than high. At first I thought it was the stock cats restricting airflow but found out that's not the case cuz I just installed APR dp's and test pipes and I'm still having the problem. I did a log on the requested and actual boost and they are very close. The Maf readings went up to 256 and this is with a GIAC 91 octane chip, I think it's the old file I'm not sure though. Boost went up to 2200 on the VAG. After I logged those, I checked blocks 22 and 23 timing pull and I pulled 10.5 at 6600 rpms. I'm wondering if that's the reason my car feels slow. Does it sound like a bad fuel pump? injectors? Thanks

Also, since I'm not running any cats, the oxygen sensors aren't reading so I have no way to log my af.

[The_Jerbel]

The 10.5 you see is the timing correction factor, and that's about normal. A little high, but still within normal range.

You have no secondary O2 sensors, but you still have the primaries, you should log those. You should also get a WB O2 sensor if you really want to fine-tune your car.

[eurofvr]

I thought my car HAD a wideband. Is that why I can't see my air/fuel on Vag-com?

Also, how do you check if your fuel pump is bad? Because sometimes my car pulls the more gas I give it and sometimes I feel no increase in power after 1/4 throttle even though my boost guage shows 19. I'm pretty sure it's not my turbo/s, they are not making any funny noises.

[The_Jerbel]

If your fuel pump isn't making any noise then it's likely still working fine. You can hook up a fuel pressure gauge to it to be sure if you want. I would replace the fuel filter before I worried too much about the pump.

If your car has a WB you'll probably see a gauge somewhere for it. The WB is totally independent of the NB sensors, which allow the car to run properly. The WB is for monitoring purposes only. You should see the air/fuel on VAG com.

I would pressure test for boost leaks and check your codes.

[eurofvr]

Thanks, I'm gonna replace my fuel filter today and check for boost leaks. I am also wondering if the massive voltage fluctuations on my o2 sensors is normal. I see that there is a specified value for each one but a 1 in particular goes up and down drastically.

[eurofvr]

Also, what block do I log for air/fuel?

[Oricle]

Also, what block do I log for air/fuel?

block 31

[eurofvr]

block 31

I'm sorry but that one is for the os voltages.

[exorcet]

I'm sorry but that one is for the os voltages.

reading 'narrowband' o2 voltages will give you an idea of your a/f ratio.. albeit depending on the condition of your o2's it can vary.. but it gives somewhat of an idea where you are.

.86 - .87 is about the range you want them to be in WOT from ~4500rpm to 7000rpm

.89+ is going towards rich, .84- is going towards lean. Again, this will give you a general idea of where you are, but not nearly as accurate as a true wideband gauge.

[eurofvr]

Okay this is what is going on. I put in a new fuel filter and it made a big difference. Can you believe nobody ever changed it? I was dated in 99 [O_O]
So yeah, it sounds better and pulls harder half of the time. Usually when I am going downhill in 6th it has mad power but going uphill it lags. It starts to pull and then backs off. Maybe it has something to do with my bank 1 os's "". Let me tell you what happened. When I removed the stock dps I cleaned both B1 oxygen sensors with maf cleaner. So now, I have the connectors crossed so because I think the pass side os is bad. Since have no cats the os in the test pipe which is now b1 sensor 1 or 2 I'm not sure, has a code for internal resistance too high. I'm wondering if I pull harder down hill because the exhaust isn't hot enough to screw up the os. IDk. I guess I'll find out. I'm gonna do the spark plug defouler thing and see what happens.

Also, I checked block 31 and all four blocks jump around like crazy at idle. Is'nt it supposed to be steady?

[Oricle]

reading 'narrowband' o2 voltages will give you an idea of your a/f ratio.. albeit depending on the condition of your o2's it can vary.. but it gives somewhat of an idea where you are.

.86 - .87 is about the range you want them to be in WOT from ~4500rpm to 7000rpm

.89+ is going towards rich, .84- is going towards lean. Again, this will give you a general idea of where you are, but not nearly as accurate as a true wideband gauge.

1.1 and above is going towards lean. .9 and below is going towards richer.

[Oricle]

Okay this is what is going on. I put in a new fuel filter and it made a big difference. Can you believe nobody ever changed it? I was dated in 99 [O_O]
So yeah, it sounds better and pulls harder half of the time. Usually when I am going downhill in 6th it has mad power but going uphill it lags. It starts to pull and then backs off. Maybe it has something to do with my bank 1 os's "". Let me tell you what happened. When I removed the stock dps I cleaned both B1 oxygen sensors with maf cleaner. So now, I have the connectors crossed so because I think the pass side os is bad. Since have no cats the os in the test pipe which is now b1 sensor 1 or 2 I'm not sure, has a code for internal resistance too high. I'm wondering if I pull harder down hill because the exhaust isn't hot enough to screw up the os. IDk. I guess I'll find out. I'm gonna do the spark plug defouler thing and see what happens.

Also, I checked block 31 and all four blocks jump around like crazy at idle. Is'nt it supposed to be steady?

Your o2 sensor should jump at idle. It means they're working. Lean, Rich, Lean, Rich.

Log 031, 115, 003

Since the late 80's o2 sensors have been self heated. If an o2 sensor is bad that wont have any control when you're wide open throttle. It runs off your tuning map.

[eurofvr]

I did some logs last night and my af is between .85 and .9 from 4500 to 7000rpms, maf g's went up to 265, and block 115 went up to 2240 at 3700 rpms and tapered down to 1820 at 6500 rpms while staying within 150 of the specified the whole way. I also logged block 2 and my injector duty cycle is %90 at 4000 rpms and shoots up to %114 to redline. I am also pulling between 6-11 degrees of timing pull. What could be causing this?

[BastardS4]

sounds like a boost leak.

[Oricle]

I did some logs last night and my af is between .85 and .9 from 4500 to 7000rpms, maf g's went up to 265, and block 115 went up to 2240 at 3700 rpms and tapered down to 1820 at 6500 rpms while staying within 150 of the specified the whole way. I also logged block 2 and my injector duty cycle is %90 at 4000 rpms and shoots up to %114 to redline. I am also pulling between 6-11 degrees of timing pull. What could be causing this?

What tune do you have? Turbos?

Let me get this straight. Your car will have power lower end, drop power mid range, gain power top end?


Anyway you can post the logs?

[exorcet]

1.1 and above is going towards lean. .9 and below is going towards richer.

um, no. Higher voltage = rich. Lower voltage = lean.

[exorcet]

I did some logs last night and my af is between .85 and .9 from 4500 to 7000rpms, maf g's went up to 265, and block 115 went up to 2240 at 3700 rpms and tapered down to 1820 at 6500 rpms while staying within 150 of the specified the whole way. I also logged block 2 and my injector duty cycle is %90 at 4000 rpms and shoots up to %114 to redline. I am also pulling between 6-11 degrees of timing pull. What could be causing this?

o2's look ok. I agree with Bastard it sounds like a boost leak, possibly. what is your exact setup?

[eurofvr]

I have the old GIAC file with stock k03's. APR dp's and test pipes, brand new n75 & 710n dv's.

I will check for a boost leak today tonight or tomorrow. Do I just hook up the tester to the 3" inlet where that is connected to the maf housing and pressurize it? or do I have to clamp off some hoses so I don't get oil in my intake?

[eurofvr]

Well guess what? I have a boost leak. It's in that small y hose going down behind the pass side dv. It's going to be a bitch to replace. I'd still like to know which hose/s I need to clamp off when doing a pressure test. I searched everywhere and did'nt find one diy. What's up with that?

[exorcet]

Well guess what? I have a boost leak. It's in that small y hose going down behind the pass side dv. It's going to be a bitch to replace. I'd still like to know which hose/s I need to clamp off when doing a pressure test. I searched everywhere and did'nt find one diy. What's up with that?

Here are instructions to pressure test:

http://www.awe-tuning.com/media/pdf/...ure_tester.pdf

[eurofvr]

Thank alot! You guys have been great help. I'll replace that hose and do a full on pressure test and hope nothing else pops up.

[The_Jerbel]

Thank alot! You guys have been great help. I'll replace that hose and do a full on pressure test and hope nothing else pops up.

Sounds like a classic case of blown F-hose...

[The_Jerbel]

1.1 and above is going towards lean. .9 and below is going towards richer.

I think that maybe you're thinking in terms of lambda...

[Oricle]

I think that maybe you're thinking in terms of lambda...

That is what the block logs.

[The_Jerbel]

That is what the block logs.

Actually, it logs O2 sensor voltages...

[eurofvr]

I removed my intake manifold and low and behold the f hose has a hugh tear in it along the inner seam. Tomorrow my power gasket will be here along with my new bosch plugs and I should running like a champ. I can't wait!!

[exorcet]

any update?

[eurofvr]

Okay, here's the update: The f-hose was replaced and a powergasket was installed. I changed the plugs to Bosch F5DPOR's as well. I'm still pulling up to 12 degrees of timing and my injectors are maxing out but it feels ALOT stronger. It still feels like I get more power at around half throttle than I do with full. I was told that the timing pull is normal and isnt dangerous but I'm still concerned about my random misfires and max'd out injectors. It might be the chip because it's GIAC file. I'm sending it in next week regardless to have the new one flashloaded as well as the 100 oct file. Methanol injection is also on the menu.

[exorcet]

Okay, here's the update: The f-hose was replaced and a powergasket was installed. I changed the plugs to Bosch F5DPOR's as well. I'm still pulling up to 12 degrees of timing and my injectors are maxing out but it feels ALOT stronger. It still feels like I get more power at around half throttle than I do with full. I was told that the timing pull is normal and isnt dangerous but I'm still concerned about my random misfires and max'd out injectors. It might be the chip because it's GIAC file. I'm sending it in next week regardless to have the new one flashloaded as well as the 100 oct file. Methanol injection is also on the menu.

make sure to 'clear codes' with vag-com and drive around to let it re-adapt. might help your timing/fuel get better. that's good they're reflashing it for you.

[Oricle]

Actually, it logs O2 sensor voltages...

Really? It's ironic how multiplying the "o2 value" by 14.7(even though it even says lambda) in the logs ends up very similar to my A/F ratio that my car was dyno tuned at. Not sure why as the "o2 value" goes down my car gets richer.

[The_Jerbel]

The O2 voltage (value) actually gets bigger as the car runs richer...

[Daft]

Okay, here's the update: The f-hose was replaced and a powergasket was installed. I changed the plugs to Bosch F5DPOR's as well. I'm still pulling up to 12 degrees of timing and my injectors are maxing out but it feels ALOT stronger. It still feels like I get more power at around half throttle than I do with full. I was told that the timing pull is normal and isnt dangerous but I'm still concerned about my random misfires and max'd out injectors. It might be the chip because it's GIAC file. I'm sending it in next week regardless to have the new one flashloaded as well as the 100 oct file. Methanol injection is also on the menu.

Timing pull is normal but, 12 degrees is excessive. What is your actual O2 voltage from the pre-cat O2 sensors while under WOT?

[Oricle]

The O2 voltage (value) actually gets bigger as the car runs richer...

Directly from ross-tech website

If Lambda is greater than 1.0, then there is a surplus of air and the engine is running lean. If Lambda is less than 1.0, then there is a surplus of fuel and the engine is running rich. It should be noted that the ratios are mass-based, not volume-based.

[The_Jerbel]

Wow, just wow. I understand very well how lambda works, thank you. I don't need your coles notes tutorial on how to read it.
You need to understand that O2 VOLTAGES ARE NOT A READING OF THE LAMBDA SCALE. As O2 voltages go up, it is an indication that there is more fuel in the exhaust, which signifies a richer mixture.
/thread

[Oricle]

Wow, just wow. I understand very well how lambda works, thank you. I don't need your coles notes tutorial on how to read it.
You need to understand that O2 VOLTAGES ARE NOT A READING OF THE LAMBDA SCALE. As O2 voltages go up, it is an indication that there is more fuel in the exhaust, which signifies a richer mixture.
/thread

What you seem to be missing is the block 31 logs lambda value.

[Daft]

What you seem to be missing is the block 31 logs lambda value.

Do you have an S4? Block 31 is O2 sensor voltages for banks 1 & 2.

Actually, my A4 was and my A6 is the same too.

[eurofvr]

Here's another update: After replacing the f-hose I have noticed increased power and a much smoother throttle response compared to before I had the leak. I am still noticing however, that I am pulling harder using less throttle than at full. Also, when my engine is warm, it seems to be lacking power compared to the other gears. I believe 6th gear at %75 to %80 throttle pulls harder than 3rd, 4th or 5th. I did a couple of logs and I am still pulling 12 degrees at times and my injectors are maxing out at around 4000 rpms at full throttle. I try not to use full throttle now. What I do is I push the throttle until I don't feel it pulling anymore and then back off slightly and THEN it starts to take off. I'm wondering if it's my fuel pump or injectors, or maybe even my ECU/chip. I plan on doing another pressure test to make sure there are no more leaks and then I will do some logs and see if I can't bring the timing pull down with lemmiwinks or something. Thanks for all the help

[Daft]

For now, you can definitely take a couple degrees of timing off the top with Lemmi just to add a little more protection until you find the source of the problem.

As for the remaining ussue, it sure sounds like you are running lean and the ECU is then forced to correct the timing. Both APR and GIAC will request a fair amount of timing but typically, they both like to see CF less than 10 degrees.

Personally, I like to see less than 5 degrees......

[exorcet]

What you seem to be missing is the block 31 logs lambda value.

http://www.ross-tech.com/vag-com/m_blocks/030-049.html
031 - "oxygen sensor voltage"

you don't know what you are talking about.. so stop being argumentative! =)

[exorcet]

I plan on doing another pressure test to make sure there are no more leaks and then I will do some logs and see if I can't bring the timing pull down with lemmiwinks or something. Thanks for all the help

that's what i was going to recommend - another pressure test. Especially considering you installed a power gasket - they can be finicky with regards to getting a perfect seal.

Make sure to use a bottle filled with soapy water and spray down everything during the pressure test.. a lot of times there are leaks to small to be heard (especially when crankcase is gargling) and you'll see bubbles form in these areas. Helped me find a few i couldn't hear.