Hi Kev no there are no fault codes, secondary is going to be difficult because I have to make some plugs between the coil pack and the plug, I don't have them. Today I went for a long drive and when the car is hot the misfire is still there but it isn't so bad as cold. Below 2000 rpm the long fuel trim went -21 and short trim reacted by doing +21. Above 2000 rpm the fuel trims are good.
This car is from another shop and they already had the cylinder head of it, and also put new hydraulic lifters in it, also they have fitted new camshaft position sensor and crankshaft position sensor.
So it is a car with quite a history.
Have you checked the valve timing? And for air leaks at idle, that would give bad fuel trims but would get better as you get further up the rev range.
I had a very similar case on a zafira with very similar fuel trims, everything else had been done by another garage including the headgasket. It was out 2 teeth on the exhaust cam. 10 mins @ idle and watched the fuel trims come back to zero.
Hi hbr,
Sorry late replying, only just got in. Just seen your message about long/short term fuel trim, it appears that you have a very rich mixture!This may now be fitting into a problem that I have seen on the smaller single cam Peugeot/Citroen engines. I have a question for you!! Has the car ever overheated?
Hello Kev, I really don't know the history of this car, I just checked the timing this is good, also did a leak test on all the cylinders this was also good. Removed the camshaft cover and checked the camshafts, don't see anything strange.
What is the problem you have seen on the single camshaft cars?
Hi hbr,
The problem that we encountered on 'all' the single overhead cam engines Peugeot/Citroen KFX 1.4 litre engine code downwards to the 1.0 litre engines, when they had overheated they damaged the injectors! Nearly all over fuelled, after rebuilding the head and reassembling to block there was a problem with engine misfire which initially caused havoc. I never got round to doing a detailed test on the injectors, but a quick check of resistance proved nothing! When we replaced the injectors the car ran perfectly, we've now encountered this problem many times and rectified it accordingly. Of course there are some exceptions to this rule, and the ones that switched the engine off soon enough appeared to have got away with it!
Hello, here is an report for this car. The injectors have been away for testing and cleaning, they where very dirty. After I fitted them back in I thought the problem was still there, so I posted this on autonerdz forum also, and I found some people there who gave the same advice as here, also found that Robski was there also so became the same advice from him there also. Won't do that again posting in 2 forums. But to keep a long story short I started the car yesterday cold and the problem seemed to be gone, also drove the car and the fuel trims where much better as the first I posted here. Started the car again this morning and the backfire and hesitation when you hit the throttle is gone, there is still a slight misfire when it runs, so my thoughts are that the coil pack indeed may have an problem as suggested here, but because the shop before me tried the coil pack with the dirty injectors they didn't notice any difference. Will try to convince them to put on a new coil pack.
Thanks for the advice given here to me, and I hope I may post again if I got a problem car back in.