Does not receive a sign an injector, Fiat Uno Fire 1.3 8V

Hello friends of this page, a while ago that I do not enter and my amazed how much it has changed !!! I have my problem, I have a FIAT one Fire 1.3 8V 2.006. One day he began to fail, pull until he was 3 cylinders. He took him to the workshop, we changed the injectors but did not get a signal to one of them; Make the central to repair which was ok, when I put the central one again, the only thing I did was clean the mace of the central and was perfect. I take it again to the workshop and go out to try it, a clock. The following day he began to pull down until he was at times in 3 cylinders, that is at times he fails to a greater or lesser extent and at times he is perfectly. I thank you for spending time and reading this and if they could help me much more. angel...

The artenerodeangel wrote: Hello friends of this page, a while ago I do not enter and my amazed how much it has changed !!! I have my problem, I have a FIAT one Fire 1.3 8V 2.006. One day he began to fail, pull until he was 3 cylinders. He took him to the workshop, we changed the injectors but did not get a signal to one of them; Make the central to repair which was ok, when I put the central one again, the only thing I did was clean the mace of the central and was perfect. I take it again to the workshop and go out to try it, a clock. The following day he began to pull down until he was at times in 3 cylinders, that is at times he fails to a greater or lesser extent and at times he is perfectly. I thank you for spending time and reading this and if they could help me much more. angel..

Check that all injector pins always have contact when installing it, and uses clean contacts to discard sulfate inside due to lack of connector insulation (environmental humidity entry I don't want to say that this is completely wet just by some moisture that avoids optimal contact or in the case that you find the engine without taking precautions) and the other checks with a test. Discard that the problem is from the connector to the ECM (if that were the case you must check the connector pins and also use clean contacts)
Are you sure it is an injector and not spark or any sensor? It is that for that symptom it may be due to many more things.

Czech muscle is very right that is not a spark or compression problem, it first detects the cylinder that has problems and then performs the spark plug, changing the cable to see how you go, you can change the position injectors, to see if the fault persists in the same cylinder to discard.

Musculorots thank you very much and apologize for the delay p The answer !!! I did what you told me about the pins, check them and closed them a little more doubts and continuous failure. I have not washed the engine just for fear of what you have written. What I could not do is measure them with the Tester PQ I don't have. What I did was take it to Viedma that is 150 km d where I live, to the official agent D Fiat and connected it to the computer, the diagnosis was that the problem is in the cables of spark plug or in some d pins (nothing that you have not said without seeing the car !!! Check. Thank you for your time and you are already welcome your QM solutions have served a lot !!!