Bob India
Member
- Joined
- Nov 14, 2018
- Messages
- 11
- Reaction score
- 14
- Your Mercedes
- A-Class 2005 A170 PETROL AUTO (W169) Facelift Version
- Thread Starter
- Thread starter
- #21
PROBLEM SORTED.
Today, I had another go at the car. I swapped ignition leads 1 & 2 with each other. Then waited for the OBDII code to change from P0351 to P0352 indicating that he HT Ignition lead I moved from cylinder 1 to 2, was faulty..
In reality, I should have done this right at the start, but was bogged down by the two error codes.
P0068 - Plausibility check of values for components B28(Pressure Sensor) and M16/6(Throttle valve actuator) in idle and under partial load. See above on how this was cleared by cleaing the throttle assembly first.
P0351 - Ignition spark insufficient at cylinder 1.
Some Background info.
This car is very low mileage. Used to belong to my mum who didn't drive it much. It's a 2005 car and in 2008 it had only done about 6,000 miles. Only used now and again. In 2008, my parents went abroad for 4 weeks. The car was left on the drive. One night I noticed a cat waiting by one of tyres. I moved the cat on. My parents returned, started the car and the engine was struggling and running Very Rough and shaking like mad. I managed to drive it to my local garage. They tried a coil from German Swedish French Parts supplier, (GSF), but no joy. Then they tried replacing Ignition leads on cylinders 1 & 2. still no joy. They gave up. So I took the car to Mercedes. They had the car for two days. I thought with their STAR diagnostics they would have the problem sorted in no time. On Day two, I told the Service manager, I wanted a diagnosis and was surprised they could not diagnose the problem in one day and that I wasn't going to pay for hours and hours of investigation !! We agreed a maximum amount. Later on day two in the late afternoon, he said the mechanic had noticed some wire had been cut above one of the ignition coils and that it would need a new wiring loop at considerable cost. I thanked him for his diagnosis and asked him to put the car back together. I picked up the car and took it to my usual garage. I took out the Air filter box and looked under the Air Tubes. I found what looked like chicken wings bones. Clearly, Rats had seen the car was not moving and had made their home under the air tubes, which is a hollow area in the engine. They had then proceeded to chomp through the primary coil supply wires. I bought some wire heat-shrink, trimmed the wires and soldered them. The car was back in operation.
We have a KFC and other fast food outlets at the top of my road. Dirty disgusting people eat their food as they walk down the road, or sit on garden walls and discard their leftovers in our gardens. I actually had my old Honda Accord in my garden which I was going to sell when I could get round to it. It was left in the garden for 6 months as I had bought another car. When I got round to starting the car, it was dead. RATS had chomped through the big bundle of wires coming from inside the cabin, to the engine. There was no way to fix the car without alot of expense and a new wiring loom. I had to throw that car away.
In a way I was lucky with the Mercedes. The rats had only chomped about 3 wires close to the ignition coil. Anyway, back to the story. I have read read on some forums, ignition leads should last at least 100,000 miles. This may be true for genuine leads. My mechanic had bought some CHEAP and NASTY leads from German & Swedish Car Parts. These leads were still in the car to this day. Lead on cylinder 1 had failed after just 25,000 miles. I had not realised the original genuine leads had been changed but I had been given the genuine leads and two cheap leads in a bag, which have been sitting in my garage for years. I put the original leads back onto the car and now the car is running sweet..
On a last note. When anyone comes to these forums looking for help and sharing their experiences, it is important to have a conclusion to their story when and if they resolve their problems. Even if they had to take their car to a garage. Let us know how and what was done to resolve issue. It will help the next person. Also, take a photo of your work progress. It's easy these days with mobile phones and auto uploading to Google photos..
I hope my experience and pictures helps someone else, and for budding mechanics who want to have a go themselves, you will need an OBD scanner of some sort. I used a ELM327 mini with the Torque Lite App. It won't do full and complex diagnosis like ABS and air bags and custom specific manufacturer features like the LAUNCH system will, but will help with some PowerTrain diagnosis. There are better and more comprehensive OBDII dongles and software, so it all depends on your budget..
Thank you all for your help and comments..
Regards
Bob India.
(I chose this user name after Ed China from Wheeler dealers.. You can learn alot from watching that program!!)
Today, I had another go at the car. I swapped ignition leads 1 & 2 with each other. Then waited for the OBDII code to change from P0351 to P0352 indicating that he HT Ignition lead I moved from cylinder 1 to 2, was faulty..
In reality, I should have done this right at the start, but was bogged down by the two error codes.
P0068 - Plausibility check of values for components B28(Pressure Sensor) and M16/6(Throttle valve actuator) in idle and under partial load. See above on how this was cleared by cleaing the throttle assembly first.
P0351 - Ignition spark insufficient at cylinder 1.
Some Background info.
This car is very low mileage. Used to belong to my mum who didn't drive it much. It's a 2005 car and in 2008 it had only done about 6,000 miles. Only used now and again. In 2008, my parents went abroad for 4 weeks. The car was left on the drive. One night I noticed a cat waiting by one of tyres. I moved the cat on. My parents returned, started the car and the engine was struggling and running Very Rough and shaking like mad. I managed to drive it to my local garage. They tried a coil from German Swedish French Parts supplier, (GSF), but no joy. Then they tried replacing Ignition leads on cylinders 1 & 2. still no joy. They gave up. So I took the car to Mercedes. They had the car for two days. I thought with their STAR diagnostics they would have the problem sorted in no time. On Day two, I told the Service manager, I wanted a diagnosis and was surprised they could not diagnose the problem in one day and that I wasn't going to pay for hours and hours of investigation !! We agreed a maximum amount. Later on day two in the late afternoon, he said the mechanic had noticed some wire had been cut above one of the ignition coils and that it would need a new wiring loop at considerable cost. I thanked him for his diagnosis and asked him to put the car back together. I picked up the car and took it to my usual garage. I took out the Air filter box and looked under the Air Tubes. I found what looked like chicken wings bones. Clearly, Rats had seen the car was not moving and had made their home under the air tubes, which is a hollow area in the engine. They had then proceeded to chomp through the primary coil supply wires. I bought some wire heat-shrink, trimmed the wires and soldered them. The car was back in operation.
We have a KFC and other fast food outlets at the top of my road. Dirty disgusting people eat their food as they walk down the road, or sit on garden walls and discard their leftovers in our gardens. I actually had my old Honda Accord in my garden which I was going to sell when I could get round to it. It was left in the garden for 6 months as I had bought another car. When I got round to starting the car, it was dead. RATS had chomped through the big bundle of wires coming from inside the cabin, to the engine. There was no way to fix the car without alot of expense and a new wiring loom. I had to throw that car away.
In a way I was lucky with the Mercedes. The rats had only chomped about 3 wires close to the ignition coil. Anyway, back to the story. I have read read on some forums, ignition leads should last at least 100,000 miles. This may be true for genuine leads. My mechanic had bought some CHEAP and NASTY leads from German & Swedish Car Parts. These leads were still in the car to this day. Lead on cylinder 1 had failed after just 25,000 miles. I had not realised the original genuine leads had been changed but I had been given the genuine leads and two cheap leads in a bag, which have been sitting in my garage for years. I put the original leads back onto the car and now the car is running sweet..
On a last note. When anyone comes to these forums looking for help and sharing their experiences, it is important to have a conclusion to their story when and if they resolve their problems. Even if they had to take their car to a garage. Let us know how and what was done to resolve issue. It will help the next person. Also, take a photo of your work progress. It's easy these days with mobile phones and auto uploading to Google photos..
I hope my experience and pictures helps someone else, and for budding mechanics who want to have a go themselves, you will need an OBD scanner of some sort. I used a ELM327 mini with the Torque Lite App. It won't do full and complex diagnosis like ABS and air bags and custom specific manufacturer features like the LAUNCH system will, but will help with some PowerTrain diagnosis. There are better and more comprehensive OBDII dongles and software, so it all depends on your budget..
Thank you all for your help and comments..
Regards
Bob India.
(I chose this user name after Ed China from Wheeler dealers.. You can learn alot from watching that program!!)