Larsson

I didn't had much time to do any testing on the truck past year. But I started again to solve the problem once and for all. I think the high pressure fuel pump is a bit faulty. I did some testing to see if the long and short term fueltrim is ok. With the engine warmed up I first plugged the crankcase ventilation to see if the long term fuel trim stays in spec. It read -3.9% at idle. Then I connected the crankcase ventilation and it read -10%. (Bank 1 and 2 read about the same percentage) So I think the high pressure fuelpump is leaking fuel in the oil. When I turn on the ignition to check the fuelpressure it stays at 250 kpa. And at idle it bounces around 250 kpa and 460 kpa. Even at 3000rpm it doesn't go above maybe 380 kpa. And the fuel rail pressure reads 400 to 500 kpa. So I think I'm going to replace the high pressure fuel pump. It could be a faulty injector but because the fuelpressure is a bit low I think the best way to go is change the fuelpump. What do you guys think?

Hi guys, I recently replaced my thermostat that was stuck open. And now it's working fine again. But I was curious about how the system works. I saw two thermostats. One small one and one big one. How does this operate? I hope to have a learning experience

It seems that the check engine light only comes on when I do short trips of 3 miles or less. Like going to the supermarket at the other side of town and give grandma a lift. When I do longer trips of like 60 or 80 miles it has no issues at all. The coolant temperature hits 210°F at these short trips, especialy now it's summertime and the outside temperature hits 80°F or more. I'm trying to apply the systemtest of Asilverblazer but I'm still learning/ experimenting how all of the tests work in combination with hptuners.

If you look at the fuelpressure which is around 360 kpa in the freezeframe, do you guys think it is a bit low? And what about the fuelrailpressure?

According to my dianostic check the troublecodes are p2097 and p2099. The last time after I reset the dtc only a p2097 popped up. As you can see in the last picture of the freezeframe. Your dianostic aid is very helpfull but the links don't work here in holland. For example, when I click on the "fuel system diagnosis" , I get a no access message on my computer. It's like the website is blocked off. Or maybe it's only for people in the US? I don’t know. Is there perhaps a different way to check the fuel and injector system? Maybe a different link? Thanks for the great input by the way.

Today I got a new check engine light. This is the freezeframe. I noticed that the downstream O2 sensors give different voltages now. So maybe it was just " domb luck"? I'm going to change all 4 of them and go from there.

I did some highway driving last week. About 400miles and the check engine light didn't came on since the last time I cleared the dtc's. Maybe the O2 sensors where a bit dirty? My plan now is to change all 4 O2 sensors and check the wiring from the two sensors past the cat. I keep you guys posted about the outcome. In the mean time every suggestion/help is welcome

I finished work early today so I had some time to check the connectors and wires of the O2 sensors. Everything looks normal. No damaged connectors or wires so far I can see. So I don't know how both the downstream sensors put out the same voltages. Maybe it's an idea just to replace all 4 O2 sensors and see where this leads to?

I'm going to look at the problem this saturday. If the weather stays dry. Let you guys know what I found. In the mean time tips are more than welcome.

I looked back to the photo I shared and noticed it too. Maybe there is a short in the wirering somewhere?

Never changed the oxygen sensors. Maybe start there? Do I have to change all 4 of them? The ones before and after the cat? And only use gm genuine

Does this help to pinpoint the problem?

I'm going to look at the fueltrims this weekend, if I have the time to do so. I'll give you an update as soon as possible. Is it a good idea to pour some cat cleaner in the gastank? Just to see if it helps?

Thanks for the reply. According the YouTube clip it is a problem with the cat. Is it a problem that relates to a lot of short trips with the truck? I have the oem headers installed.

Hi guys, my 5.3L silverado has a strange dtc code which keeps on popping up. I can read the dtc with the hp tuners OBD2 scanner/reader but I can't figure out what the code means. I can delete the check engine light message but after a few hours it comes back on so there is something going on according the computer. The problem is I can't figure out what is going on. Does anyone has an idea? I took some pictures from my laptop of what's wrong according to hp tuners.