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P0170 fault code for fuel trim malfunction Bank 1 of 1

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47K views 42 replies 4 participants last post by  RANDY P  
#1 ·
I got this code P0170 fault code for fuel trim malfunction Bank 1 of 1 on my 1996 C 280, I just hang up the phone with AutoHausAZ in frustration. I gave them my VIN # WDBHA28E3TF349999 and they still ask me what month my car was built. (I changed the last 4 digits) For the past 20 years I have been living in the hospital over 12 hours a day,(Radiologist) So I do not know anything about cars, I just drive them. Why people in the car industry give us hard time with tons of questions? All I want to buy is the sensor that is inside the MAF, what is so complicated about this? AutoHausAZ said they have three units for my car, 0280217500 and 0280217517 and
0280218080 how so? and I am the one to furnish an answer? did I make the car? Can someone please help? I am very frustrated right now!
 
Discussion starter · #3 ·
I purchased a can of BG Mass Air Flow Sensor Cleaner $10 Bucks, I removed the Sensor ONLY, but it was very clean, I sprayed it anyway, put it under the sun to dry, I then removed the MAF housing and I sprayed it too! After confirming that all is dry, I put everything back together, I started the car, everything is fine, but the "Check Engine" light is still "ON". I did not erase it, I am now driving to reach over 100 miles and see if it will go away. My office is just 4 miles from home, so it will take a while to reach 100 miles. I believe that the Fuel Filter has not been changed for the last 6 years. I found the Air Filter Very dirty, I went to two auto supply stores and no one have it, and so I ordered a MANN from autohausaz.com, will be in shortly, I cleaned the air filter as well as the housing, vacumed it, was full of bugs, sand, leaves etc. The car runs great and smooth, in fact it starts better than before. By big question to you the Group is: What should my NEXT course of actions be, without making financial mistakes? I really do not think it is the MAF, only because it was very clean already, and I also handled it with great care, and I only sprayed the bottom.
 
Discussion starter · #5 ·
What is an MOT valve? I wish I knew, I would I cleaned it, last Saturday I cleaned the censor inside the MAF, I also cleaned the MAF housing. But I have no clue what is an MOT Valve and where it is located.
 
Discussion starter · #7 ·
A million thanks Randy P

Thanks a million Randy, for the past hour I was reading all your posts about the MOT. I think this is the culprit the MOT. I can't wait till I go home tonight and work on the issue in my garage. In fact I may leave early today, cause it is nice and sunny here in VA. I will buy the CRC Throttle Body Cleaner.
 
Discussion starter · #9 ·
I just used BG MAF Cleaner. I removed the "L" shape little black tube/hose, and it was in my hand and I sprayed it several times, and put it on the table for an hour to fully dry, then the other end rubber hose is longer but I could not take it out, instead I sprayed only on the one end, I then sprayed the actual unit on both ports the "IN" and the "OUT" I then put back all the way I found them, I took the car for about 10 miles to do errands, Groceries, dry cleaners, blockbuster. So I started the car at least 4 times and then went home. The "Check Engine" light is still "ON" though! Oh and I did put the end of a long flat head Screw Driver, and I can feel the KNOCK on my fingers, I also touched my ear on the handle, "BOY" I can hear everything, the unit is working. I will by the break cleaner tomorrow, just to have it handy. I do not know how to erase the code. I need help on that please, and Thanks in advance. On Monday I am receiving the Air Filter from AutoHausAZ.com via UPS.
 
Discussion starter · #11 ·
Hi again, In the event that I will need a new MOT valve, then who sells a genuine? is it BOSCH ? where did you get yours? I am not sure yet that I need one. I just want to be ready to order should the need arises. I will try your suggestion in getting rid of the "Check Engine" light first and see what happens. One more thing, where is a good Under the hood complete diagram to be able to navigate and understand what is what I am looking at under the hood of all these parts, is there a schema or PDF or even a CD/DVD? or even online for the 1996 C 280 please ? Thanks
 
Discussion starter · #12 ·
This morning, I turned the key untill all lights light up, but did not started the engine, I waited for over 1 minute no lights turned off. I then proceeded cranking the engine, so I can go to work. The "Check Engine" light is still "ON" :(
 
Discussion starter · #15 ·
I just used the OBD II and found this time TWO codes, the usual one of P0170 but now a new one P1700, I then cleared them. and drove the car for about 10 miles. NO lights so far, let us see what happens. Now I am running normal with no lights on dash.
 
Discussion starter · #17 ·
if it flips out again, scan the car.

If NO CODES show up, then do the key trick.

don't reset if there are no codes, don't drive around with scanner plugged in it pisses the car off and the CEL goes on in protest.

I know all about this since I chased my own tail for a month - I would drive around with the scanner plugged in since the CEL always came on but no codes then discovered it was the tester doing that to the car.

rjp

The check "Engine LIGHT" came back ON. go figure!! :(
 
Discussion starter · #20 ·
I contacted The Brinson Company since they are located next door to me here in Virginia, They said that for my car I cannot buy just the MAF INSERT Sensor, cause it is round in my car 1996 C 280. The sensors only part is rectangular for newer than 1996. they quoted me $250.00 So now I rearened that I will have to buy the whole MAF assembly. Any thoughts ?
 
Discussion starter · #22 ·
I did not buy anything yet, I am close but did not. The code has always been the same, it is the code that is now imbeded in my mind 24 hours a day night weekends, my life is on hold due to this code P0170
P0170 fault code for fuel trim malfunction Bank 1 of 1
This code never goes away, I cleaned the MOT purge inlet/oulet, I cleaned my MAF, I replaced the AIR Filter, I replaced the GAS filler CAP. I replaced the OIL filler cap, In January I had my oil and oil filter changed. In February I had my Body Throttle sprayed with BG Body Throttle spray. This past summer 2010 I had a tune up, spark plugs replaced. I shall never forget this P0170 code, and YES my "Check Engine" light is still "ON" and yes I am still driving around with the light "ON" what is strange, is that there are no symptoms, the car runs fine! why don't I ignore that light and go on with my life?
 
Discussion starter · #25 ·
171,133 exacttly as of THURSDAY morning. Please help me figure it out Randy, the car runs like new though! nothing wrong with the car other than the "Check Engine" light is on. When I use my friends OBD II to erase the light, the light comes back on after 50 miles or so. I am embarrased on keep asking my friend at the office to erase my light, one of these days, he will tell me to buy my own!
 
Discussion starter · #28 ·
Yes, I will order the MAF from Autohausaz, I am wondering though, what does the MAF has to do with "FUEL" or "FUEL TRIM" I did not see any lines that passes fuel inside the MAF! what exactly does the MAF do? and why is it there? I will also do some googling and see what is the role of a MAF and why my code points to FUEL TRIM Bank 1 of 1
 
Discussion starter · #30 ·
I FOUND THE CULPRIT

measures airflow and adds fuel to the appropriate amount so the engine runs right

When it goes out of whack the other sensors try to compensate but once you get past a certain point it can't add anymore and you get a nice MAF code.

Fck, I hate MAF issues.

rjp

I open for my final inspection before going to the internet and spend $200 for a MAF, and here is what I have found. There is a rubber tubing that is bent like a half circle that goes onto the MOT, one end is all cracked and, I cannot replace it, because there is a white mini tubing in the center of the half circle rubber balck tubing, I will need to order it. Please help me find the part number. Please review the pictures below. Please help, I am close in fixing this problem. Byt for now and for a TEMP solution I put some 100% silicone caulcking where the crack is.
 

Attachments

Discussion starter · #31 ·
measures airflow and adds fuel to the appropriate amount so the engine runs right

When it goes out of whack the other sensors try to compensate but once you get past a certain point it can't add anymore and you get a nice MAF code.

Fck, I hate MAF issues.

rjp
Here is the silicone on the top of the tube to seal the air TEMP
 

Attachments

Discussion starter · #33 ·
A2024760123 Part Number

I hope it works. YOu sure you can't just replace the hose with some universal fuel approved stuff from the auto parts store? I don't recall mine having any plastic insert to deal with...

rjp
The good news is that after that I put 100% silicone around the crack, that cracked tube has been SEALED and therefore the vaccum leak is fixed, and no longer get the engine light anymore, I drove the car for 300 miles and no more engine light. The bad news is that the cracked tube is a unique part that only the dealer sells it, and they want $30.00 plus tax for this small tube, I called AutohausAZ and they do not carry it nor order it, and they do not know who does, so my question is, what other online parts store should I TRY? I know I can get it a lot cheaper than the dealer, but do not know who sells it, Part Number A2024760123 or without the A 2024760123. Thanks
 
Discussion starter · #35 ·
go to pelicanparts.com they'll probably get it.

Beware, since it's dealer only there isn't going to be much of a discount either way.. BTDT with these parts stores.

If it's leak free, just leave it alone?

rjp

HELP! I got the "Check Engine" light back ON after 400 miles
Same fricking CODE! Hey! is Bank 1 the passenger side or the driver side ?

P0170 fault code for fuel trim malfunction Bank 1 of 1