No Boost - No Codes - SOLVED

5 posts in this topic

Hey Folks,:D

So I finally broke down and decided to have the turbo looked at in my 450 by and independent garage.

A short recap. Last summer, from one day to another I lost boost in the car. The question was always, was it a lack of boost or Limp Home mode?

The car didn't throw a code or CEL so I started digging.

1. the hose from the EGR to the turbo  - It happened to me before when I repaired the intercooler so I reinstall the pipe. - no change
2. EGR is stuck - I remove and check it. I had put a blocker plate last year - Nope slides perfectly
3. intake pressure sensor mounted near the dipstick - Nope
4. intake pressure sensor mounted on the intercooler - Nope in tight.
5. limp home mode. - disconnect the battery for 10 minutes - Still no power
6. leaky waste gate pressure hose (the short one that goes from the turbo high side barb to the actuator head) - Looks good
7. Struck waste gate - Lubed and loosen but seemed OK. I lengthened the arm to see if it was not sitting well - Nope
8, Bad Intercooler - I changed out the Intercooler with a used one but in good condition and pressure tested.
9. Bad turbo - I removed the intake and it looked clean with no broken fins or free play
10. Pressure test with a rubber clip and a plastic plumbing fitting that I connected a fitting to connect to my compressor. Block off the Intake to the motor with a plastic sheet and see if it holds boost. - No leaks.
Finally I brought it to a independent garage I found who deals almost exclusively in Smarts. He found the problem in no time with a more elaborate code reader. His code reader showed a problem with the high pressure pump.
** It was the connector to the high pressure fuel pump. **
Somehow the connector was inserted but not clipped in to the end. When he pulled it came off in his hand! He plugged it back in and the car ran like it was new.
$60 and it was fixed! After all of the hours I spent trying to figure it out.


I highly recommend this garage if you're in the Montreal area and need service for your car. If, like me, you cannot stand bringing your car to the Stealership where you get robbed blind.

The owner is Norman Comeau

200 BOUL LAURIER, McMasterville, QC
J3G 1P8
He is very knowledgeable and showed me exactly the issue without a big production.
I love my 450 and people ask me often if they should consider one. I always have to say that they are great if you know how to fix them because I have never found a garage that knew anything about them.
Also, as some may recall my experience with the dealer borders on litigation.
I can now recommend the car with the knowledge that someone can have it serviced at a reasonable price by competent mechanic.

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There is no pressure sensor on intercooler.  That sensor is for inlet air temperature. 


On our CP1 high pressure pump the pumping element that can be disabled as fitted with a cut off solenoid. As I recall, pump element is enabled when solenoid is not energised. Solenoid simply operates a pin that keeps inlet valve in open position when solenoid is energised. The purpose of the cut off solenoid is solely to allow the pump to operate only two pumping elements, resulting in less engine power being consumed at low engine loads.

Disconnecting connector would therefore make all three pumping elements operate at all times. 

I could of course be wrong so need to check this tomorrow morning.



Solenoid is seen on right hand side of above photo. 



Solenoid pin is just visible in above photo. 


PS. Good news you got yours sorted. 

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Looks like I’ve been a false prophet for many years spreading incorrect information. Pin in last photo of previous post clearly sticks out quite a bit most likely enough to keep inlet valve open thereby disabling that pumping element. Solenoid of course is not energised as disconnected from the car. Must fathom out this issue tomorrow at first light. 

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it took me a few weeks to get mine running after re-installing the engine (i bought it with engine out)


i was close to giving up on it after spending so much time fixing it and figuring out which bolts went where.....then i checked all connectors and the one on my pump was not clicked in enough


it started soon after..thats my only experience with that connector

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Thanks for the clarification of the Inlet air temp in the intercooler and pump Tolsen,

I guess I'm not the first to confront this issue but it seems rare.  It is a major PIA because the clip appears OK until you pull on it and only with a more advanced diagnostic tool does the code show up. The high pressure pump being disconnected doesn't throw a CEL but does put the car in Limp Home mode none the less.

In any case we should add it to the list of possible reasons for a Limp Home mode. Especially if you've been working on the car.

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