Strong engine vibration when idle

[v530anh]

Yesterday I had to carry several 20kg of tile cement, the guys said it was at the legal limit and I could not carry anything else, and would have to make another 10 mile journey to the store, all is well and dropped everything off at my house. Then I started the car again for the second trip and car was struggling to start. So I took my GPS out of my car socket, and switched the radio off. Still vibrating when idling and I stuck a voltmeter into the socket. The car seemed to struggle to get to 3.9 Volts and then would drop. There is a cheap battery in the car which is not silver calcium, I have a silver calcium in the shed. Normally the battery would charge to 4.3 or 4.4 volts.

 

Another thing, the battery light went on when I tried to start the car for the second trip to the store only once, and when coming back when in idle the revs would increase automatically and I would have to switch  the engine off and on. This happened 3 or 4 times. 

I am guessing it is not the engine mount because when at idle I increase the revs From 800 to 1200 the vibration stops.

[isetta]

"and I stuck a voltmeter into the socket", which socket?  the cigarette lighter socket?   it should read at least 12.6v without engine running and about 13-14 volt with engine running. At the voltage level you mention there is no chance that there would be enough to make the starter motor work. 

[v530anh]

I stuck the voltmeter in the cigarette socket, when cold it was 12.5V. 

[v530anh]

OK Forscan says:

 

===OBDII DTC P1131-C===
Code: P1131 - Lack of HO2S11 Switch Sensor Indicates Lean

Status: 
 - Confirmed - malfunction is confirmed 

Module: On Board Diagnostic II

Diagnostic Trouble Code details

HO2S11 not switching correctly. Sensor indicates lean.

Air leaks at the exhaust manifold

This DTC may be caused by :

Low fuel pressure.

Manifold vacuum leak.

HO2SHTR11 Heater Circuit Malfunction

===END OBDII DTC P1131-C===

 

and ....

 

===PCM DTC P1131===
Code: P1131 - Lack of HO2S11 Switch Sensor Indicates Lean

Module: Powertrain Control Module

Diagnostic Trouble Code details

HO2S11 not switching correctly. Sensor indicates lean.

Air leaks at the exhaust manifold

This DTC may be caused by :

Low fuel pressure.

Manifold vacuum leak.

HO2SHTR11 Heater Circuit Malfunction

===END PCM DTC P1131===
 

Any idea how to fix? Is it a garage job? Cost to fix?

[v530anh]

update

I changed the battery to a silver calcium one - still same problem but I have a spare battery now

copy and past part:

Symptoms of a Faulty Mass Air Flow Sensor
A faulty mass airflow sensor will cause problems similar to low compression or low vacuum, and will also show symptoms similar to when your vehicle has low fuel pressure from a faulty fuel pump. Here are some of the most common symptoms of a faulty mass airflow sensor:

• The engine is very hard to start or turn over
• The engine stalls shortly after starting
• The engine hesitates or drags while under load or idle
• Hesitation and jerking during acceleration
• The engine hiccups
• Excessively rich or lean idling

 

so i have ordered one for 75-10 discount=65 pounds

maybe the cone filter created the problem, so i put my k&n back on

[Tuha]

To check mas air flow sensor simply unplug it and check if car works the same/worst/better. When you unplug sesor ecu will work with default map without it.

Regarding to codes i would advise to check o2 sensor

 

[v530anh]

11 hours ago, Tuha said:

To check mas air flow sensor simply unplug it and check if car works the same/worst/better. When you unplug sesor ecu will work with default map without it.

Regarding to codes i would advise to check o2 sensor

 

It does work better when I disconnect the sensor. But with the sensor connected revs go to zero everytime I have to stop. Also noticed with the sensor disconnected when I go into neutral as I like to roll down my road the revs increase to 2000, but when go has stopped the revs are 900 normal.

Though it is interesting that you mentioned the Lambada sensor, as I remember reading something about servicing it in the Haynes manual but I could not work out where it was. But I think a faulty oxygen sensor will give a warning light.

[Tuha]

It's screwed to you exhaust near engine around catalisator. Looks like hudge bolt with wire. Can't miss it!

i can make picture how it looks on my firsta mk6 if you want

[v530anh]

OK, this is the next thing to do after my Haas maf sensor comes. There are some cheaper maf sensors on eBay, though they say OEM maybe they are imitations?

[Tuha]

You can try to clean old one (green part).(On eBay you can find sprays to do that, just be careful about touching it cause it`s very gentle and it`s easy to brake it)

[FatHead1979]

I clean mine every few months (1.8 TDCI MK2) using electrical contact cleaner and a couple of cotton buds, easy to do if it's similar to the above type sensor.

[v530anh]

I did clean it last year when I fitted my cone filter, and tried cleaning it again when problem arose HO2SHTR11 Heater Circuit Malfunction does suggest a fault with maf. Delivery expected today.

I suspect cone filter was guilty, did some research on the net and it seems they can damage the maf.

Anyway I have not told the insurance company about the modification, so I have put my old k&n panel filter.

[mjt]

53 minutes ago, v530anh said:

HO2SHTR11 Heater Circuit Malfunction does suggest a fault with maf

That sounds to me more like a Heated Oxygen Sensor (H-O2-S), i.e. Lambda sensor in the exhaust. That's just a guess though.

[Tuha]

Agree with mjt.

[v530anh]

I also agree with him, though a bad maf seems to have same symptoms as a bad o2 sensor. Though I have ordered a special socket for o2 sensors from China 22mm is that correct?

[v530anh]

Haas maf not working. Car does not start when it is connected, disconnect it and everything is fine. Have to return it and order a more expensive one from carparts4less.