I have a 99 cummins with no major mods cat turbo auto trans. the problem i am haveing is that the truck doesnt have much power on takeoff and it will switch through the gears but the turbo will only hit 10 pounds of boost untill u hit 40mph then it will spool up and take off screaming info on possible problems woupd be very helpful???

 

Any codes? They sure would be helpful for diagnosing.

 

Low boost sensor voltage and overboost code

 

Could be your MAP sensor, or the wiring to it. It would be a good idea to inspect the harness, plug, and sensor for any damage.

 

I will check that tma i have a fuel leak on a injector line at the head woul that cause it? Any info on fixing that leak would be helpful as well i am new to cummins

 

Unless the fuel leak is excessive, it shouldn't effect performance much. If the fuel that is leaking has gotten into the MAP sensor it may cause your issue.



1. Lift Pump
2. Fuel Return Line (to Fuel Tank)
3. Fuel Supply Line (Low Pressure, to Engine)
4. Fuel Heater
5. Water-in-Fuel (WIF) Sensor
6. Fuel FilterlWater Separator
7. IA T Sensor
8. Map (Boost) Sensor
9. Fuel Drain Manifold
10. CKP Sensor
11. CMP Sensor
12. Overflow Valve
13. Drain Valve
14. Fuel Pressure Test Potts
15. ECM
16. ECT Sensor
17. Fuel Injection Pump
18. Throttle Lever Bell Crank and Apps
19, High-Pressure Fuel Lines
20. Fuel Injectors
21. Fuel Heater Temperature Sensor (Thermostat)
22. Oil Pressure Sensor
23. Fuel Injector Connector
24. Drain Tube
25. Intake Manifold Air Heater/Elements

As for the fuel leak, try tightening the fitting where the fuel is leaking from.

 

The fuel was leaking bad out of the number 4&5 injector lines out of the head and it got just about everything on the left side wet! Do u have any idea what could be causeing that leak at the injector lines on the head

 

If the nut that screws into the head is loose it will leak, or if the connector tubes are damaged. This will cause high pressure fuel to leak out. There is also an o-ring on the connector tube, and it seals return fuel into the head.

 

I just ordered the new orings today so i hope that will cure the problem as far as the map sensor i will check tht tma! Would that map sensor cause it to do it all the time bc it only does it every now and then

 

If it is an intermittent fault, it will cause intermittent results.