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Matt
Matt, Mechanical Engineer
Category: Vauxhall
Satisfied Customers: 21851
Experience:  BEng hons Mech engineering, in auto industry 22 years
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P003a code turbocharger/supercharger boost control a has exceeded

Customer Question

P003a code turbocharger/supercharger boost control a has exceeded maximum learning limit
Submitted: 1 year ago.
Category: Vauxhall
Customer: replied 1 year ago.
Vauxhall Corsa 1.3 diesel
Glow plug light flashing and service light on.
Car starts first time
Increased fuel usage and drop in MPG from 65 to 55 since fault occurred
No faults with any fuses.
Expert:  Matt replied 1 year ago.
HelloI'd say that either the turbo is overspeeding or there's a leak thats losing your boost so the system is trying to compensateI'd 1st suggest to first check all the high pressure hoses post turbo/s for any split hoses or cracked metal pipes, also check the ends of the intercooler as its not unheard of to pop the end caps off under high boost. If this is OK then check the small vacuum lines to the turbo and its connected control solenoid on the bulkhead, any cracks or leaks can give turbo issuesAlso have a feel around with your bare hands with the engine running to see if you can feel any escaping gas under your touch. Another method is to use a soap and water solution sprayed onto any suspect areas - if there's a leak it'll bubble up with the engine running Also check that the vacuum hose running to the dump / turbo bypass valve is intact with no leaks as if the dump valve is opening prematurely you'll be losing all your boost If this is OK then remove the high pressure intake hose after the turbo and have a feel of the turbine wheel - there should be no play radially at all - but a little bit of axial / end to end float is normal one other possibility is that the wastegate actuator spring has gone soft so allowing the wastegate to open prematurely - if your actuator has a threaded end you can increase the preload on it to see if this improves things otherwise these units are quite cheap compared to a new turbo so it may be worth trying a replacement If this is OK then check for air leaks after the mass airflow meter - The best way to locate a leak is to have the engine running and warm and then spray lighter gas /propane around each joint in turn. If the engine rev's up you've found your leak.Work your way through each possible joint one at a time and you should find it. I use a slightly flattened piece of brake pipe and some rubber hose from the can of lighter gas to provide a spraying 'wand' and allow a direct blast of gas into each area, especially those difficult to reach with large implements.
Customer: replied 1 year ago.
Could it also not be something to do with any sensors? I've taken the car to the garage and they ran the diagnostics and said they were unfamiliar with the code displayed and that this would have to go directly to Vauxhall.Was hoping it would be something simple to resolve but doesn't sound like it will. The car still drives fine but I have lost some power but obviously don't want to continue driving for long periods incase this leads to further damage.
Expert:  Matt replied 1 year ago.
hello a faulty sensor can produce this issue but the things I've suggested are pretty cheap to check so I'd push on with those 1st if this doesn't help then yes it would be beneficial to pull off the codes with a Vauxhall specialist
Expert:  Matt replied 1 year ago.
hello a faulty sensor can produce this issue but the things I've suggested are pretty cheap to check so I'd push on with those 1st if this doesn't help then yes it would be beneficial to pull off the codes with a Vauxhall specialist