I installed a sct tuner on my truck and used the default street flash and my #3 injector promptly took a dump. Will a tuner kill injectors?

I just finished up oil cooler rebuild studs, blue spring and egr delete.

Now it looks like i have more injectors going bad.

I have 147,000 miles on the truck.

 

If the tuner caused low fuel pressure then it is possible but just the act of putting the tune on there wouldn't cause it. Wide open throttle + low fuel pressure = possible injector damage. Do you have a way to monitor fuel pressure? It needs to remain above 45 PSI at all times including WOT.

 

I dont have a fuel pressure monitor yet. But i just did the blue spring update before putting on the tuner. Should that not make sure i had enough fuel pressure? Should i check the fuel filters now?

 

It should raise the pressure about 10 PSI but if the fuel pump is getting tired or the fuel filters are plugged then it wont help. I had mine tuned with the SCT canned 65 HP tow tune and hit it with WOT and the pressure dropped into the 30's and that was with the blue spring so I replaced the fuel pump now it only drops in to the mid 50's at WOT. So I would take it easy on the throttle until you verify the fuel pressure.

 

ok i will do is there a cheap way to look at fuel pressure? like under to hood?

 

I would suspect the Blue Spring installation is the culprit.

Also trash on the IPR screen

Josh

 

how would the blue spring kill injector?

wouldnt trash on ipr screen affect more than one injector?

 

There are several variations in the fuel housings and lots of extra parts in the Blue Spring Kit. Sometimes 1+1=3 and there is loss in fuel pressure.

Loss in fuel pressure kills injectors.

Just pay attention to IPR% during crank, cold idle and hot idle and watch for symptoms.

Josh

 

A standard mechanics fuel pressure tester will work fine. You could even rent one from one of the chain parts stores (usually for free)Only issue is Fuel pressure test port thread fitting size is M12x1.5. Most gauges are 1/8" NPT so you'll need an adapter that's not usuially in the kit. You can buy one for less than ten bucks online from GloShift or Autometer, or maybe find one locally if there's a hydraulic supply place nearby.

One other consideration that's a little harder to work around is that the 45psi figure is under full throttle conditions. 45psi at idle is too low and even if you see 60psi it could still drop considerably at wide open throttle. The dealership has a FP testing set-up the has a bleed orifice and a small return line that drains back into the tank (at the gas cap) to simulate WOT. So, the options are use a shop gauge and place it where you can see it and watch pressure at WOT, permanently (or maybe temp I guess) install an electric sender and gauge in the truck. Or pay a dealership to test it.

Injectors are expensive and it's worth the effort and cost to know the fuel pressure is correct, especially if you're having running issues and suspect it's not.

 

So I had my mechanic friend come by and hook up his computer.

It turns out that when my #3 injector died the computer was compensating for it.
So fuel pressure is good, but the computer was still compensating like #3 was out still.

#3 injector was out of sync with the rest of the injectors.

So he synced it and reset the cam sensor. It cleaned right up and ran great.

Now that I have started it a few times it feels like it is rough again.

Could my cam sensor be going bad? it didn't throw a code yet.

My crank sensor has a leak could it be going bad to cause this too?

 

Re-synced the injector and reset the cam sensor.

Mechanic speak for; "I have no idea what happened, but I have to make something up to charge you for my time"


Josh

 

He is a military friend that didn't charge me to hook it up. But I still need to know what is really going on.

 

How do you know the fuel pressure is good? The only way to know is to install a gauge start the truck and take it for a WOT run while you watch the pressure. The PCM has no way of knowing what the fuel pressure is because there is no sensor on that system.

 

I was pretty much thinking the same thing.

 

if fuel pressure was low wouldn't you be able to see a drop in injector pressures?