NewBeetle.org Forums banner

1 - 20 of 43 Posts

·
Registered
Joined
·
94 Posts
Discussion Starter #1
Grabbed this screen off my blue driver obd II scanner app.
MAF seems to respond to acceleration. Also cleaned it the other day.

What do you all think?


Sent from my SM-N975U1 using Tapatalk
 

·
Registered
Joined
·
13,410 Posts
To test the maf, you would want to see; the min and max reading @ WOT (wide open throttle), in 2nd gear.


The AEG engine is rated at 85kW @5200RPMs. This converts to 113.9 HP. 80% of 113.9 = 91.12 g/s. So provided the engine good, your peak Grams Per Second reading on a 2nd or 3rd gear pull should be around 91. Different things will effect this reading, but it should be in that ballpark.

It looks like your scan tool/app; is setup, to read in (standard) pounds per minute, vs grams per second (metric). You might look into the app pid preferences and see, if you can convert from standard to metric readings. Otherwise, the 2.0L readings; would be this, converting over to standard.

113.9 HP. 80% of 113.9 = 91.12 g/s (12.05 pounds per minute) max reading
at idle mafs typically read somewhere from 2 to 4 g/s (0.26 to 0.52 pounds per minute) at idle


So, start with scanning for trouble codes and post any you find; then, you could do a minimum and max @ WOT maf test, to confirm, it is working as it should. If you end up needing a new one; stick with oem BOSCH mafs and buy it from a reputable supplier, as there are many counterfeit Bosch parts, being sold in the internet, places like ebay. FCEPEURO, could be a good supplier and offers lifetime warranty, on all the parts they sell.

Also, I would check your fuel trims and see, if it is in the + or - 10% range.


As each new thread is created, we do not have everything in context; it would be preferable to keep things together, so we can refer back to all the things you have tried or replaced up until this point.

I don't know, if when you cleaned it, you replaced the gasket or if you did a throttle body alignment but that is a common thing to do, which can fix many rough idle issues. If you cleaned the throttle body and DID NOT, do the throttle body alignment, the car will run badly, as the settings have been lost. This is typically done with a VW specific scan tool; like VCDS by Ross Tech, OBDeleven or the lesser "VAG" type Chinese knockoff quality scanners.

 

·
Registered
Joined
·
94 Posts
Discussion Starter #3 (Edited)
The very basic test that I did on the MAF seems to indicate its working. Idle was equivalent to .3 g/s and 4000 rpm was about 15 g/s. Btw, does the 2nd gear test apply to Automatic transmissions?

I was really concerned with the O2 sensors readings and especially sensor 2 reading "N/A".

Oh, Throttle Body was cleaned on intake manifold and no alignment was done yet.
 

·
Registered
Joined
·
13,410 Posts
Are your maf readings pounds per minute or grams per second? Your screen shot of your app reading; is in pounds per minute. You can convert this to grams per second if you want using a online converter.

 

·
Registered
Joined
·
13,410 Posts
If in fact, your readings are in g/sec; then you min is good but your max is low!

3 g/s @ idle and max @4000 rpm was about 15 g/s. Typically, idle is 2-4 g/s and max is around 90 g/s.

Basically, we are dealing with the engines max volumetric efficiency; view the engine as a air pump and we want to know, what the mass air flow readings, at its maximum air being pumped through the engine....is!

As to the 2nd gear @ WOT; we are trying to get the engine, at its max ability to pump air and thus, the high rpm, by staying in a lower gear. In the 01m 4 speed; I assume, you can take the selector out of "D" and manual position it in , 2nd gear, then do WOT, to get your max MAF reading.

So, if your readings are posted in grams per second; your maf is under reading and could be defective.

Did you find any trouble codes? I would get the throttle body alignment procedure done; this can affect how the engine runs and affect, other readings as well.
 

·
Registered
Joined
·
94 Posts
Discussion Starter #6
If in fact, your readings are in g/sec; then you min is good but your max is low!

3 g/s @ idle and max @4000 rpm was about 15 g/s. Typically, idle is 2-4 g/s and max is around 90 g/s.

Basically, we are deal with the engines max volumetric efficiency; view the engine as a air pump and we want to know, what the mass air flow readings, at its maximum air being pumped through the engine.

As to the 2nd gear @ WOT; we are trying to get the engine, at its max ability to pump air and thus, the high rpm, by staying in a lower gear. In the 01m 4 speed; I assume, you can take the selector out of "D" and manual position it in , 2nd gear, then do WOT, to get your max MAF reading.

So, if your readings are posted in grams per second; your maf is under reading and could be defective.

Did you find any trouble codes? I would get the throttle body alignment procedure done; this can affect how the engine runs and affect, other readings as well.
I will retake my readings with the software set to metric and see what it reads.

I do have an issue with the Tiptronic switch F189 (plastic piece looks like it broke or slipped out of place) that keeps me from switching gears, but I'm able to get into Drive and Sport mode.

I routinely get a P0300 or variant.

Robert



Sent from my SM-N975U1 using Tapatalk
 

·
Registered
Joined
·
13,410 Posts

Being, you have the convertible; sounds like you have the 09G six speed trans with Tiptronic feature? If the shift selector is messed up; this can affect, how your tranmission shifts and it should be tested, to see it if is defective. Again, this testing and reading for trouble codes; would require a VW factory level scan tool, like VCDS by Ross Tech, OBDEleven or equivalent, that can read live data and reader blocks.

Here is a video, showing; how you can read live data, for the transmission:


Your current troubleshooting and testing requirements; could really benefit, from the use a VW specific scan tool, to work on your New Beetle. This would enable you to do the throttle body alignment and test your tranmission.

Buying, one of these tools: would definitely pay off, in the long run and are really, worth the investment!
 

·
Registered
Joined
·
94 Posts
Discussion Starter #8
Yes, verified that I do have the 09G. Ive actually seen the manual shift display come up once. Knowing that I think the electronics are ok. What I did notice is that most of the dust cover shield/belt is either missing or broken. After disassembling it today I discovered a small part with a small round magnet. Just where might that go?

Any idea on the best way to fix this?

Robert

251145


251146
 

·
Registered
Joined
·
13,410 Posts
This should help: sometimes, things can be repaired, glue things back on the selector portion or get a used one; typically, you need a new one. While not cheap, this part is crucial, to correct operation of the transmission and it is used, daily, to drive the car. They all wear out and break eventually.

 

·
Registered
Joined
·
94 Posts
Discussion Starter #10
Getting back to my rough idle. I've located a couple possibilities. Throttle body looks okay though.

Breather hose is blocked on smaller tube. Is this intentional?

20200912_140014.jpg


This piece off the brake booster is severely cracked on both ends. Not sure why they used a hard plastic material in-between two soft rubber fittings?

20200912_140003.jpg


Where the heck is the pcv valve?




Sent from my SM-N975U1 using Tapatalk
 

·
Registered
Joined
·
94 Posts
Discussion Starter #12
Did you clean it, replace the gasket, (you did that already) and do the throttle body alignment procedure?
I cleaned while it was still attached to the intake manifold when I had removed it to replace the cylinder head and gasket. So the gasket was not replaced.

Awaiting VCDS scanner to arrive. Then I will be able to do the alignment.
 

·
Registered
Joined
·
13,410 Posts
Vacuum leaks, can definitely affect the idle and fuel trim readings. Replace the brake booster hose; if it is cracked, this is a very common issue.

Is this the same part # on yours?


VacuumPIPE.
1C0612041N Product Image
Part Number: 1C0612041N
 

·
Registered
Joined
·
94 Posts
Discussion Starter #16
Vacuum leaks, can definitely affect the idle and fuel trim readings. Replace the brake booster hose; if it is cracked, this is a very common issue.

Is this the same part # on yours?


VacuumPIPE.
1C0612041N Product Image
Part Number: 1C0612041N
Yes. Looks identical. I will definitely replace that soon.



Sent from my SM-N975U1 using Tapatalk
 

·
Registered
Joined
·
13,410 Posts
Unfortunately, these aren't cheap; from what I can tell, this one is only available as a genuine VW part at this pont. Online, they seem to be in the $80-$130 range, depending on who you buy it from.

For my 1.8T, I was able to get the equivalent hose from rmeuropean; at a really good price, typically if they don't' list it on their website they don't carry it but you might contact them, see if they can get it. European Auto Parts at discount prices | RM European or since your close, contact Largest Car Part Warehouse | Replacement Auto Parts Online | AutohausAZ.


Meanwhile, you can try two ways of dealing with it. Sometimes, you can repair it; by snipping off the split part and heating up the hard hose end with a propane torch or heat gun, then shoving it back on the plastic connecter, then let it cool. I did this on a Audi TT, I was working on and there was enough room left on the that is worked ok but it may not work, if it doesn't reach.

For a temporary solution, until you order a new one; wrap with electrical tape around the split and use a hose clamp, to keep it air tight and secured to the plastic end.
 

·
Registered
Joined
·
13,410 Posts
As to the breather hose; did you clean it out and see, if there is any debris, you can push out, etc? Many of the pcv hoses, get filled with oily and carbon junk; I'm not familiar with that particular hose, I would assume it would breathe, allow crankcase vapors to pass through it but I don't know for sure.
 

·
Registered
Joined
·
13,410 Posts
251197


As to the PVC valve; it looks like, you might have one similar to the 2.5L engine and it is under a black plastic cover, where the silver heat shield is on the intake manifold, on the front of the engine? I haven't worked on this particular engine and can't seem to find anything in the online service manual. You might check it out and see, if it is in fact there.
 

·
Registered
Joined
·
13,410 Posts
The diaphragm, is known to fail on the 2.5L and cause a unregulated large vacuum leak, so this might be a possible reason for your problem? Thankfully, the aftermarket, has come up with a repair kit, that replaces the diaphragm without having to replace the whole plastic intake manifold. I don't know, if this works with the 2.0L or not; you might need to do some more research?


251198
 
1 - 20 of 43 Posts
Top