Need correct PSI reading at fuel pressure rail.

[Mysilvi]

Hey guys, my truck crapped out pulling out of my driveway and it didnt want to start initialy. I had to turn it over a couple of seconds before it started then let warm up and as I was pulling out it just died. I put a guage on the fuel rail and it was reading 60ish PSI. If I recall I think it should be greater than 60 right?? which makes me believe that its the fuel pump for the 5TH time!!!! Thanks in advance..

 

[Aloicious]

this is a vortec right?

if so it should be around this:
58-60psi with key on engine off and the pressure should hold there fairly well, it shouldn't bleed off too quickly...

idle should be 55-58psi

 

[Mysilvi]

Thanks Aloicious, you would think since its the 5th time I would have writen it down or somthing... But I think it was at the value you mentioned and that makes me think somthing else is the problem. Yes its a Vortec 5.7 litre and I tested it when it was dark out so really dont remember the PSI that it exactly was but do know it was over 60PSI with the engine cranking over and held over 60 when stopped with no drop off. I am at work now took the Tahoe in and when I get home will further look into it. Thanks again for the much needed support!!!

 

[jdyates]

Thanks Aloicious, you would think since its the 5th time I would have writen it down or somthing... But I think it was at the value you mentioned and that makes me think somthing else is the problem. Yes its a Vortec 5.7 litre and I tested it when it was dark out so really dont remember the PSI that it exactly was but do know it was over 60PSI with the engine cranking over and held over 60 when stopped with no drop off. I am at work now took the Tahoe in and when I get home will further look into it. Thanks again for the much needed support!!!

Do you run it low on gas a lot? Someone once told me that our fuel pumps overheat VERY easily when the tank has I think under 1/4 gas in it. I'm not sure if that's just us TBI guys, but something to think about.

 

[Mysilvi]

Funny thing is I was on my way to get gas then work. It was just above E when it happened but was only running for about 3mins before it died.
I have heard about this from guys that work at Nappa when I bought my last pump and tank replacement..

 

[jdyates]

Funny thing is I was on my way to get gas then work. It was just above E when it happened but was only running for about 3mins before it died.
I have heard about this from guys that work at Nappa when I bought my last pump and tank replacement..

Might be on to something. I've had my truck about 2 years and haven't had to replace my pump yet, it's been on E a total of twice. My OCD (not really lol) doesn't let it go under half EVER.

 

[Mysilvi]

Im starting to think it might be ignition issues and the rain. We had a heavy rain over night and when my truck angled down the driveway I let it sit for a sec to get all the water out of the bed and when I went for the gas it died. NOW thinking back a month or so when it was Reaelly humid out I did some local running around and my truck was kinda sputtering but would not die when idled. I would get on it like the plugs were either fowled or somthing was wet and try to burn it off...Have to check for spark, need to be home but its great to get ideas now!!

 

[Mysilvi]

Ok, I am ruling out the fuel problem and test confirms this by pressure readings of 63PSI when key turned on but not starting engine and a dropp off to 58PSI very slowly 5mins. I have no spark and think its the coil. I tried to test for power out of the coil and have nothing, tried reading through the coil and had infinity which tells me the coil is open. I do have power going to the coil at the orange wire so the coil seems to be the problem do you guys agree????

 

[Mysilvi]

Hey just an update finally got around to testing today and Found that the ICM seems bad. Will change it out tomorrow stupid little thing is 80 bucks!!

 

[Aloicious]

did you already buy the new ignition control module?