VW Beetle Forum banner
1 - 5 of 5 Posts

·
Registered
Joined
·
17 Posts
Discussion Starter · #1 ·
just had a coolant issue I described in another thread - had a cracked hose that was leaking at only certain rpms - mechanic fixed this. coolant had leaked out and was visible under the hood but not sure where it touched. now CEL light has come on and I've experienced for some weeks where feels like it will die while idling. has never died but feels weird, also feel some hesitation. codes P0172 and P1127 came up. had MAF replaced already this January. could it be dirty MAF? my mechanic is very reputable but couldn't seem to find the problem when I complaied about the rough idle earlier - however codes had no come on yet. confused! could it be o2 sensor? do they normally replace that with MAP replacement? anything else?

thank you.
 

·
Registered
Joined
·
15,839 Posts
16556/P0172/000370 - Ross-Tech Wiki

http://newbeetle.org/forums/new-member-forum/58776-trim-bank-lean-p1136-rich-p1127.html


P1127 Volkswagen - Long Term Fuel Trim B1 System Too Rich

PDF Share Code

0 P1127 Volkswagen Comments | Add Comment
Possible causes
- Faulty HO2S
- Faulty Mass Air Flow Sensor
- High fuel pressure
- Canister purge solenoid stuck open
- HO2S harness is open or shorted
- HO2S circuit poor electrical connection


Read more: P1127 Volkswagen Long Term Fuel Trim B1 System Too Rich OBDII Engine Light Trouble Code | Engine-Codes.com

Lots of possibilities; as you can see from the links. What kind of scanner are you using; can you read live data/trim levels? Is the issue; less or more severe, if the fuel tank is fuller or with less gas? Looking for vacuum leaks and testing the fuel pressure; would be a good place to start, based on the info from the above links/codes. Are you willing to work on the car yourself or want others to do the repairs? Give us more info about your scan tool, mechanical abilities and willingness to be "hands on" with the repair and we will go from there...
 

·
Registered
Joined
·
17 Posts
Discussion Starter · #3 ·
Hi Billymade,

thanks for you reply.

I'm using a cheap scanner which didn't come with an operating manual and just shows the code and a brief description. I don't think it showed details about trim levels and I inadvertedly also deleted the codes from the vehicle using same scanner... which is unfortunate as my mechanic doesn't hear the touchy idle issue I've described in the past and now doesn't have the code info. don't notice any difference in how it is acting with more or less fuel but haven't really been looking for that. it did idle much more roughly at one point and I believe I actually WAS very low on fuel.

I would love to work on the car which is why I am here actually. but don't have a garage, just have basic carpentry type tools, and biggest problem is I have trouble identifying parts under the hood. I was able to identify the MAF, however and it looks clean atleast from the outside- no oil in top of it or anything and looks pretty new (as it was replaced in Jan this year). didn't get into the filter but I believe I have identified the filter housing and looks like you jus thave some screws to take it off? I cannot find the o2 sensor - is it under the plastic for the motor or elsewhere? also confused about vacuum tubes - how do you know which tubes are the vacuum tubes?? there seems to be tubing everywhere. where do they come from and where do they go? are there many? sorry, I am pretty lost...
 

·
Registered
Joined
·
15,839 Posts
16556/P0172/000370
Contents [hide]
1 16556/P0172 - System Too Rich, Bank 1
1.1 Possible Symptoms
1.2 Possible Causes
16556/P0172 - System Too Rich, Bank 1

Possible Symptoms
Irregular behavior
Possible Causes
Fuel system
Excessive fuel pressure
Leaking or contaminated fuel injectors
Leaking fuel pressure regulator
Low fuel pressure or running out of fuel
Vapor recovery system
Air leaks after the MAF
Vacuum leaks
Improper seated engine oil dipstick
Stuck EGR valve
Oil overfill
Cam timing
Cylinder compression
Exhaust leaks before or near HO2Ss.

The 02 sensors are on the exhaust system of the car; under the car and are screwed into the exhaust system/pipe. Replacing them; is not hard but the car would have to be jack up and you might need a special socket to get it off and a ratchet. Checking the fuel pressure; would require the use of a fuel pressure tester, which can be borrowed from most auto parts stores. Exhaust leaks; can be found by examining the exhaust system but the car would need to be jacked up or put on a lift.

What brand and model of scanner are you using; can it read live data or trim levels? To look for leaks; I would take the engine cover off and start looking at all the rubber hoses and look for anything cracked, broken off or not connected anymore.

Here is a link; that shows a common hose problem.

http://newbeetle.org/forums/2-0-liter-gas/53806-misfire-rough-idle-when-start-cold-wheater.html

If you can; scan the car now and post any more codes, you are getting.
 

·
Registered
Joined
·
15,839 Posts
If you wouldn't mind; filling in your "public profile" with the year, model, engine, trans etc. info of your car; that would be helpful as well.

Once we get that info and any current trouble codes; hopefully we can help you more intelligently.
 
1 - 5 of 5 Posts
Top