CP3 psi ?
- Thread starter AdaMax
- Start date
Next question , Can injectors that balanced ok be bad and cause a knock in the engine that sounds low ?
Here's the story . Its my local townships truck . It started smoking and they drove it a few miles back to the garage . I go up and change the fuel filter and bleed it . I hooked up my insight gauges to it and it only builds up to 1000psi of rail pressure while cranking . We gave it a little shot of ether and it started up . The rail pressure bounced from 3600to 5200 while idling and the injectors balanced with a low of -3.2 to a high of +3.8 .
When running it has a knock that sounds low in it . Here's the kicker it only has 14,xxx miles on it but its out of warranty . They are going to contact GM to see if they will help with it but I don't see it happening .
When running it has a knock that sounds low in it . Here's the kicker it only has 14,xxx miles on it but its out of warranty . They are going to contact GM to see if they will help with it but I don't see it happening .
the knock stays with it and it gets worse as it runs . They said it was ticking and had lost a little bit of oil pressure compared to where it usually runs when they parked it .
yes you do. they can be returning all the fuel. That is one of the common problems. Smoke at idle, Fuel in crankcase, returning fuel is the 3 main reasons youll find bad injectors.
Check the balancer to see if it is running true. Sounds also like it could be a broke crank. Just a thought
Built motor , duel fuelers , 60's overs , gtx4202r
Built motor , duel fuelers , 60's overs , gtx4202r
the loping idle could be bad fpr
dont spray it with ether again unless you have it hooked up with efi live and the glow plugs relay shut off!!! bad bad bad bad!!!
dont spray it with ether again unless you have it hooked up with efi live and the glow plugs relay shut off!!! bad bad bad bad!!!
Ether can be bad news if used wrong, if your using a baby shot of it to build enough crank speed to build rail pressure you will more than likely be fine. I have done it MANY times and never had any issues.
Where I see bad stuff happen is when people bury them in cold weather and it pools up in the intercooler until it catches then bam enough uncontrolled easy burning fuel to hit 8+k rpm instantly and 8 broken exhaust bridges and bent push rods.
Where I see bad stuff happen is when people bury them in cold weather and it pools up in the intercooler until it catches then bam enough uncontrolled easy burning fuel to hit 8+k rpm instantly and 8 broken exhaust bridges and bent push rods.
It was a baby shot just to get it to start . Its not really loping just smoking and knocking . The thing that scares me is they said the oil pressurer dropped 20# below its normal operating psi when this happened .
super diesel
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Low oil pressure and lower end knock? Is the oil pressure still kind of low? If it is, I agree with blackdirtymax. It sounds like a spun main bearing or broke crank you got there. It will get louder with RPM.
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