QuestionI have a check enine light going off and he code comes up Low boost? Just wanted to know what the usual problems may be,and a posible fix ? EX: While going up hills it takes awhile for turbo to kick in! Thanks, John....
AnswerI could not provide a good answer as I would guess that it was a sensor of some sort kicking that light off but I am not good at diesel mechanics so I found you this..
SOUNDED LIKE A START.
I agree that this code only shows up when the truck neeeds some "extra" power. My '96 is mainly a ride to/from work or to the local dump. It's had a pretty pampered life. I replaced the vacuum pump about 2 weeks ago, I know you fellows like the TM instead, I was very, very close to installing a TM myself but at the last minute I backed out.
Blueburby, you said that it could be "waste gate solenoids" You give directions to check a (one) solenoid in the checklist. Is there more than one?? 3. Check the vacuum line running from the actuator to the solenoid(driver side of engine near intake manifold...has two vacuum lines, check these lines for any cracks or breaks, but be careful, it’s easy to snap them(in which case repair any vacuum lines as necessary).
1. Check all battery connections and grounds. This is important as the PCM can do all kinds of weird things without proper grounding. Done on a previous troubleshooting quest.
ENGINE OFF
2. Check that you can freely move the waste gate actuator(mounted on the turbo with a vacuum line running to it)(remove vacuum line and move actuator while placing your finger over the vacuum port, you should be able to get suction and pressure)if you get no pressure/vacuum playing with the actuator, replace actuator. All is good here. All vacuum/hoses were checked w/ my MityVac hand pump.
3. Check the vacuum line running from the actuator to the solenoid(driver side of engine near intake manifold...has two vacuum lines, check these lines for any cracks or breaks, but be careful, it’s easy to snap them(in which case repair any vacuum lines as necessary). All is good here
4. Follow the vacuum line back to the vacuum pump, with the Belt off, see if you can turn the vacuum pump, you should feel resistance due to the pumping action. Also feel for grinding...any grinding or lack of pumping, suspect unit. Vacuum pump is 2 weeks old.
ENGINE RUNNING(belt replaced and hoses reconnected)
5. Check for vacuum at the solenoid. If you have no vacuum AT the solenoid and the vacuum line is good. Replace vacuum pump. Good vacuum here,
6. Check MAP voltage on scanner or with DMM/DVOM, I WILL EDIT WITH THE CORRECT VOLTAGES SOON, if the MAP isn’t responding with the correct range...replace MAP Not done
7. Check for vacuum coming OUT of solenoid(solenoid should activate and buzz when truck is idling)if no vacuum or solenoid not functioning. Replace solenoid. Yes, vacuum. Blueburby has better hearing than I, didn't notice any buzzing over the diesel engine running.
8. Check for vacuum at actuator, if no vacuum at actuator, recheck vacuum lines. All is good here.
9. If you STILL can’t get the system working, the problem may be the PCM. Find a test unit(spare PCM) OR Order a Heath GL-4 and Turbo-Master(if you choose to upgrade, if you want to leave stock or have thrown a ton of parts at it...just get the GL-4/or a factory PCM)
This is just a guide, and you should post back your testing results BEFORE purchasing and replacing parts...we will help you along, and I hope you enjoyed reading my guide
