[New04project]

2004 b5.5 auto 1.8t AWM - bone stock as far as I am aware

These two log snippets where taken as part of a diagnostic attempt. I'm curious if anything stands out as an issue in them. I don't know enough about these cars of cars in general to understand. They maybe normal.

How or why would a engine load get up to 132%? It seems to be consistent that it gets to that point. Also during this log I never depressed the accelerator pedal past 75-85 %. This was in moderately normal driving conditions. The log shows I was WOT or at 100% many times. It appears that the ecm thinks I was flooring it when I was not?

The next log was during a 2nd gear to redline (or near) to check the MAF. I wish I could have done in in 3rd but I don't have an area nearby that I can go from 0 to 80 safely. I seem to recall a 130 or 140 g/s is near max on a stock 1.8t and I'm getting above 150+ g/s? Is this correct, or is my car perhaps not stock , or my MAF jacked up?

Bottom line, Is 130% engine load normal? Is 100% throttle angle when not WOT normal? And is 150+ g/s MAF readings normal on a stock 1.8t AWM automatic?

 

[PZ]

Check your requested vs actual boost to see if the car is chipped as the MAF readings are a bit high. I don't know about the throttle readings. I wouldn't be surprised if the ECU sees the MAF flow as the engine load.

 

[New04project]

Interesting, I logged boost at the same time as the throttle position and the load. Based on these I would say its not chipped. Check that off the list of things causing other issues. Still the throttle %'s seems strange. I may just have to take you up on that throttle body PZ. I definitely cleaned it and the maf at the same time. Maybe I jacked both of them up.

Side note for anyone that has been following along with my issues and Valve Body rebuild. Yesterday I was driving stop and go, and had a weird 2nd gear shift. Then the TC lockup acted the way I feel it actually should. Today I drove to the store after a night of cooldown and the TC locked up the way I wanted it to. For the first time since I purchased this car the tranny is acting better. The 2-3 shift is still firm, but a major improvement and step forward.

 

[PZ]

Since you are not chipped, I suspect the MAF is bad. What did you clean it with? I cleaned one many years ago in a bag of alcohol, but it didn't work afterward. For your load%, the MAF is showing well over the programmed amount of airflow, which should be how the ECU gets its load%.

 

[New04project]

Thanks, I'm thinking I'll order a Bosch one off eBay. It's worth the 100 to see if it is fudging stuff up. I cleaned it with crc maf cleaner, and cleaned the throttle body with crc throttle cleaner. I'm guessing it was possibly buggered up from the get go. But if the ecu was seeing above normal load, I could see ithe TCM asking the trans to shift firmer than it would normally. Idk it's worth a shot.

 

[PassatCRO]

I would also suspect bad MAF.
Your spec boost seems normal for stock 1.8T, but MAF values not.
For the throttle, what i have found on mine 1.8T manual is that i dont need to prees pedal all to the floor to see that throttle valve angle is on 100%. So i would say that if you press pedal to 80% with your foot, ECU can open throttle valve on 100%. Ecu adapted to your driving style.

 

[New04project]

That makes perfect sense. The way my car accelerates has been erratic since day one. I do typically aggressively press the pedal till it gets going then back off. It creates a smoother take off and expectable shifts for the most part. Thanks for the clarification on the throttle angle. With no codes, and minimal experience this has been a tough nut to crack, hopefully it's cracked. I purchased a maf last night, and will report back with an update. Thanks

 

[New04project]

So as promised, here it is. A post new maf report.

It runs like total crap. FML And by that I mean the idle fluctuates, misfiring on all cylinders, system lean, fuel trims up to 25%, and new codes that have not ever showed up for some reason. All in all I think this is remarkable that it took a new maf to throw these codes pointing to things I've suspected for a while...

For instance, a year or so ago I posted about my braking being different than any car I have drove. Low and behold today, a brake booster code popped up. Another, I've been hearing a "hiss/shhh" for months and suspected a boost leak, or worst case a turbo bearing. Today, pressure drop code between turbo and throttle. Another, my MPG has been absolute garbage but trims were +-2%.. now short 25% and long 18%. How has this car been hiding these codes for months, but install a maf and BOOM, all hell breaks loose. And how is it that I just logged boost last week and the values where so close to matching, but now I have a boost leak big enough to throw a code!?!

4 Faults Found:

17705 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)
P1297 - 001 -
17544 - Fuel Trim: Bank 1 (Add)
P1136 - 001 - System too Lean
17519 - Oxygen (Lambda) Sensor Regulation: Bank 1
P1111 - 002 - System too Lean
17887 - Brake Boost Vacuum System
P1479 - 008 - Mechanical Failure - Intermittent

I realize Im an idiot for waiting for a computer to confirm what I have pretty much known for a while. But at least I am not concerned about the shifts or acceleration patterns.

So the title of this thread remains "Something is funky" over and out.

 

[New04project]

Well I reset all codes, spent the afternoon running all the basic setting tests I could, vac checked the DV, and boost leak checked. Every thing tested ok. Guess the noise I'm hearing is the turbo. Sigh. And there is something up with the braking, but that'll have to wait. Went for a drive and no codes came back except misfires. When parked the car started bucking and misfiring. Went to block 33 to watch the upstream O2 sensor. It was fluctuating wildly from 25% to -25%. Resulting in multiple flashing check engine lights with misfires and then open loop. In closed loop it idles flawlessly. The voltages were ranging from 1.4v to1.7v. I captured this phenomenon on video, feel like I photographed bigfoot.

Not sure what happened with this new maf, or if the car just freaked out with different readings. Regardless it is not idling well. Like it was a year ago. If any of this signals something, let me know.

 

[PZ]

Did you try a vacuum or pressure test on all post-check-valve sections of the hoses? It's possible the vacuum reservoir side has a leak and a normal boost leak test will not check that. It could be the hoses or even the brake booster.

 

[New04project]

With a little spare time today I farted around. The only thing I figured out was that I have a screw in my tire, and it's going flat. I read a post one time about a Passat getting hit on the driver's side quarter panel and it cracked the vac res. Tomorrow I'll try to evaluate that. I'll pinch the line to the break booster and pull a vac on the line going into he wheel well and see what happened.

Strangely enough, I logged the new maf during a 2nd gear pull, and the results are the same as before. Peaked at 150g/s. Not even sure how that's possible, but it seems unlikely both mafs are fudged in the same exact way. Who knows. The idle is still really stumbly, but if it adapted before, it's likely it will agian. Thanks PZ, it'll buff out eventually.

 

[New04project]

So if anyone is following this, something interesting happened today on the mission to figure out the brake issue and stumbly idle. I was checking lines with propane and didn't find anything till I got to the brake vac pump. I jiggled the hose and the engine sounded a little different. I shut the car down and hooked up vag. Looked at the misfire counters. I proceeded to jiggle and watch. Cylinder 3&4 we're going nuts, like 50-70 misfires each. Didn't seem like it was running horribly, but the sensors were picking something up. I'll try and recreate that situation tomorrow and see what's up.

Tried something else today, when the car is running I pressed and held the brake. It slowly sunk to the stop. Engine off, the pedal is rock solid. Not exactly sure what that means? A internal leak in the master cylinder maybe? Like with booster, it's got enough pressure to leak by the piston, but no booster there isn't enough force. The car stops fine but it really seems kind of dangerous in an emergency situation. I'll update this if anything ever gets sorted out.