Ford Focus 1.6 TDCi 2008 (FIXED)

[Deleted]

I got lumbered with a Ford Focus 1.6 TDCi today, the customer complaint was that the engine is seriously holding back and will not accelerate over 40 MPH. Difficult one today because I had no scanner to check live data or fault codes, so I asked the boss to check it using his scanner. He said a crankshaft sensor fault code was present and ordered a sensor, I however was not convinced that this sensor would change anything. After trying that and no further on I was asked to check the turbo system operation, however I'd no miti vac to test the operation of the system so the boss told me to go to the auto-electricians and let him test it. After his tests he advised that the vacuum to the turbo was low and that I had a leak?



I brought the car back to the garage and visually checked all the vacuum hoses and did not find a mechanical type fault. Digging around in the back room I was sure the boss had a miti vac even though I'd not seen it for some time. Anyway I eventually found it and then tested its operation to make sure that it worked OK. I tested the vacuum at the pump and got 30 Inch Hg. I tested the vacuum at the VSV valve at the rear lower cylinder block area, the vacuum was at least 25 Inch Hg. I then tested the vacuum outlet and found the vac was 18 Inch Hg. I then moved to the turbo vacuum supply and tested the vacuum there and found 18 Inch Hg. I was happy that the vacuum system did not have a leak. I then turned my attention to the EGR system, thinking that the EGR was vacuum controlled, however I found it is not and so could rule out a vacuum problem there. I asked the boss could he test the operation of the EGR on his scanner, it seemed he could not and told me to go back to the auto-electrician and ask him. he put his scanner on and very quickly jumped through the menus, I thought your not trying and then he said his scanner would not check the function of the EGR. Back at the workshop I was not convinced the turbo system had a problem, and even though the EGR could not be tested, I was not convinced the EGR had a fault either. Before I did all this testing and going to the auto-electricians I did manage to put a hand held OBD reader on the car this morning and found no codes stored and no freeze frame data, which basically told me that nothing was wrong with the systems I've just wasted all my time on.



Anyway tonight talking to the customer I asked him had the car been serviced recently and he said yes, I asked him had the fuel filter been changed and he said no. I said that might be the problem area but I'll not through the parts cannon at it until I'm sure. I decided to let the engine idle and then I put my foot to the floor on the accelerator pedal, the engine revs only achieved about 3800 rpm. I decided at that point that I should test the mass air flow meter. AD advised there is 5 wires and the plug has six positions. I checked for a battery supply which I had open circuit and when connected was 5V. AD advised that the mass air flow meter should produce between 1Khz and 5 Khz between various pins of the mass air flow meter with the ignition on. The maximum frequency I could achieve from the mass airflow meter no matter how many times I tested it was 766 Hz. I've sort of convinced myself with these readings that the mass airflow meter is faulty. I have ordered a new one for the morning and hopefully that will cure the problem. I'll let you know how it goes tomorrow. I don't see this as firing the parts cannon based on the readings recorded from the tests.

[Deleted]

I have been evaluating the differences between the Focus and Volvo Peugeot setups, and these are the differences I have found;





Engine speed (idle) Focus = 790

Engine speed (idle) Volvo = 799

APP position (%) Focus = 0

APP position (%) Volvo = 8.1

EGR valve duty (%) Focus = 19.2

EGR valve duty (%) Volvo = 76

EGR valve position (%) Focus = 0

EGR valve position (%) Volvo = 100

Fuel rail pressure (psi) Focus = 3778

Fuel rail pressure (psi) Volvo = 4281



Everything else looks in order. The car won't accelerate properly and based on the above I'm now sure I should start with the APP position.

[trickydicky]

Dec 18, 2019 0:47:55 GMT 1 @hybrid said:

I have been evaluating the differences between the Focus and Volvo Peugeot setups, and these are the differences I have found;





Engine speed (idle) Focus = 790

Engine speed (idle) Volvo = 799

APP position (%) Focus = 0

APP position (%) Volvo = 8.1

EGR valve duty (%) Focus = 19.2

EGR valve duty (%) Volvo = 76

EGR valve position (%) Focus = 0

EGR valve position (%) Volvo = 100

Fuel rail pressure (psi) Focus = 3778

Fuel rail pressure (psi) Volvo = 4281



Everything else looks in order. The car won't accelerate properly and based on the above I'm now sure I should start with the APP position.

Does APP% change as you push the throttle pedal down??

[Deleted]

So I got very confused with this diagnosis using my latest snap on scanner. The live data on my older scanners would immediately react to throttle changes and the observer would see the digital data change, however on this scanner which uses a scan module so is wireless connection the data on screen does not seem to change. I started to believe that there was something wrong with the react time from the ECM and was advised about checking with Ford for a software update, however I decided against this and after comparing the Volvo data, which for some reason seemed to react faster than the Focus but was still slow, I thought today I'll use the pin data and check out all the sensors and actuators on the engine system and see where that leads me. So I rang the boss this morning and asked him to get the younger lad to put the Focus on the class 7 ramp so I could do some testing. When I got there the other bloke was working on the car and told me that the turbo vacuum pipe was leaking, and I replied no it is not I checked that more than once and pressure tested it also, and then he said he had used windscreen washer tube to bypass the vacuum pipe and had the engine running normally, but it was then intermittently failing. When I pointed out that there was nothing wrong with the vacuum pipe he said he had wished he had not touched the car and walked off, thus I was then left to sort it out.

The scanner data shows the turbo to be working and after comparison to the Volvo turbo (same setup) I only saw marginal differences but had to also take into consideration the engine speed variations. After comparing these two engine setups and sort of convincing myself that they are from the same family, I was sure that the differences seen pointed to a problem, however experience has shown that comparing data like I have done above should not be done as it is and will be misleading, thus sending a person down the garden path. I think I have learned a valuable lesson there. 

The boss was convinced that there was something wrong with this length of vacuum pipe that I was more than adamant there was nothing wrong with it, he wanted me to believe that the pipe could be collapsing internally when the vacuum was applied, I suppose he had a point, but my experience based on the Ford vacuum pipe fitted was telling me that it was a proper hard re-enforced vacuum pipe and unless it was somehow permanently kinked, which would cause all vacuum to be lost and not part of it, then my view that the pipe was in good working order must stand until proven otherwise. 

I went in today to get the scope out and go through a full and proper test routine but the boss was having none of it, get the parts cannon out and fire some more parts at it. So the boss goes out in his car and then rings me from the side of the road somewhere and starts going on about this vacuum pipe, which I said there is nothing wrong with it, where he then said that the power loss was intermittent, which I had never experienced with this car during any road tests I'd done, and I've done about three or four. I said to the boss if you believe that the fault is intermittent then the best option is to order a VSV valve for it and try it. he told me to ring Ford and when I did the guy on the phone could not identify the valve. I explained it was fitted at the lower cylinder block face above the driveshaft, but the parts computer probably does not show it, although I did not know the proper name of it, I did explain it was for the turbo vacuum system. The Ford guy asked me if any part numbers were on the valve and I said I'll need to ring you back and remove it. After removing the valve I could not see any numbers on it, so quick thinking I popped next door to a group of young ladies who by average must have better eye sight than us old gets, and one of the younger ladies could see numbers and did write them down for me, which turned out fruitless because the Ford guy said they did not cross reference to anything. 

The boss is now searching the web for one of these valves which he is now holding in his hand. I started to look on his computer at what he was looking at and I asked him what are you looking at and he said, "I don't know because I don't know what the valve is called", so I said why didn't you ask! He was looking at fuel injectors?

After identifying the turbo boost valve which was available on the net but needed it today if possible the boss rang Ford back and now they could identify it they wanted nearly £300 for it, which put the boss off and he said, "what if that does not cure it"? Well I said you'll just have to get one and try it. I know I'd of liked to of have the opportunity to test the systems out first but that is not his way. We managed to get one from a local factor and when I fitted it I revved the engine which sounded much better. I then took the car for a road test and the car drove fine. I got back to the garage and put the under-shield back on and the engine cover, and decided to do another road test now with the scanner connected again.

Interestingly comparing the data up to now I can't see anything different, the turbo operation looks the same as previously. I can only assume that the boost valve electrical function side of the valve had failed, but if that is the case, what I can't then understand is why did the scanner not pick up a fault code for it, but today with a new valve fitted the scanner has actually recorded a fault code for the boost valve? I cleared the fault code and did not experience it coming back, but why did the old boost valve not produce a fault code, I'd had that valve off previously also?  

The other confusion I had was with the vacuum system operation at the turbo. I used a separate vacuum pipe to the turbo waste gate and applied vacuum to the turbo watching the operation of the waste gate rod. I applied enough vacuum to operate the rod over its full working stroke, which was about 18 in Hg. The engine operation (engine revving) never came clean and the engine acceleration never restored. So I had to conclude that the power loss was not caused by the engine vacuum supply, but the electrical function of the turbo boost valve itself, which is more than likely why I did not recognise a problem using the scanner live data function.