Discarding of high fuel consumption with injector replacement

For months I have been noticing a quite high fuel consumption in my truck, I would say that it has increased by 40% compared to what I am used to. The curious thing is that the truck has never shown any symptoms of failure that made me think that the root of the problem is in some sensor or other elements. So I have been discarding step by step the elements related to the fuel system that could be the cause of such high consumption. The pressure regulator remains close to 50 psi, which is common in this type of vehicle. I have not identified any leaks in the hoses, in the tank or in any connection, everything in that sense seems to be fine. I also changed the spark plugs.

Another thing I did was to scan the car, we checked all the sensors and in terms of voltage and parameters are working well, there was nothing to call attention, however, we could draw a conclusion after the scan and it is related to the injectors. After monitoring the injection pulse for several minutes we realized that it remained stable and low, it was about 1.98 milliseconds at idle and when we accelerated it increased normally, so it was not explained by any sensor or parameter because there was so much fuel consumption, so thinking about the injectors was the most logical thing to do. I mean that the most likely was that the injectors had some wear or some physical failure that made them inject more than they should, so the recommendation of the mechanic was to perform maintenance and test them with specialized equipment.

So that's what we did and the results indeed showed that these were injecting a little more than these should, so replacing them became the next step. My truck was using Siemens Deka injectors 33007127, these have only one hole and are quite old, so the thought of more modern ones gave me hope that I could solve the problem.

After researching carefully, I found out that the most recommended replacements were the 0280155710, I looked for them all over the city, but I could not find them, so I had to go to MercadoLibre where they were available and at a very good price, $14 each. Many brands manufacture this type of injectors and the ones I got are ZCN brand, a brand that is unknown to me, but they were the only ones available on the market at a good price. This experience of buying these injectors gave me to understand that they are not very easy to get, I had to travel about 60 kilometers to pick them up in another city.

I changed the 6 injectors immediately after arriving from removing them, I must admit that I was nervous to think that any of them would have a failure since changing any of them meant having to travel to another city again, but in the first ignition all of them reacted positively.

These injectors are 4 holes and with a much lighter shape, I have no doubt that they will improve performance and in fact my initial impression has been positive, the truck has better acceleration response and idle feels much smoother. Well, it is too early to tell, I replaced the injectors just yesterday, so it remains to test the truck for many kilometers to make the measurement and draw conclusions. I hope it has been solved, I know that this truck is naturally high fuel consumption, but even knowing that I found that it was above average, to be more specific about 4.6 km per liter when normally should be about 8 km per liter.

Then I will give you my impressions about it, this situation frankly became quite uncomfortable because the truck has never shown any symptoms of failure and even has not been throwing smoke, which we know is a symptom of an incorrect mixture. All this has been a complex unknown, but I hope it has been solved.