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Matt
Matt, Mechanical Engineer
Category: Car
Satisfied Customers: 22258
Experience:  BEng hons Mech engineering, in auto industry 22 years
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I have a 2009 vw golf 1.6 tdi blue motion,the car juddered

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I have a 2009 vw golf 1.6 tdi blue motion,the car juddered a bit then stalled I tried to start the car then oil pressure warning light came on then would not start again checked dip stick but oil is ok can you help
Submitted: 2 years ago.
Category: Car
Expert:  Matt replied 2 years ago.
Hello the oil pressure light will come on if the engine revs are low, so unless the oil liight comes on with a running engine then don't worryif it won't start then try checking some basics 1st check forspark by removing one of the spark plugs and plug it back into its lead andrest it on the metal of the engine ( DO NOT hold it on place by hand) then have your assistant turn the engine over whilst you watch the plug. It should give a fat blue spark at regular intervals. If not then check that there's power to the coil pack (at the other end of the plug lead) using a meter. If there’s 12V at the pack but no spark then check the ECU power supply (fuse and relay) and also the connections to the crankshaft speed sensor. If there is a spark and its still not starting then its likely that the ECU isn't opening the fuel injectors, if the injectors are working you can hear them click - its difficult to hear them with background noise so use a long screwdriver like a stethoscope, placing the handle end in your ear and the metal tip against thebody of the injector whilst your assistant turns the engine over.If you can't hear anything check the ECU power is presentby measuring voltage at the fusebox and on its relay socket if OK then checkthe connections to the crank speed sensor and consider replacing this sensor ifthe wiring / connections look OK If the car willstart using a squirt of quick/ easi start into the intake then this confirms the problem is lack of fuel Also its worth checking that the electric pump that feeds the injectors is working correctly, it shouldrun for a few seconds then switch off when you first turn the ignition on. Ifyou remove the filler cap to the fuel tank and listen inside while your assistant flicks the ignition you should hear it clearlyIf the connections to this are corroded or damaged then the pump could stop at any time. Check that its relay switches in and out and the relay contacts are clean and bright– replace the relay if in any doubt and do the same for the fuse, ideally measure the voltage at the pump and check its getting 12V.You should begetting around 3 bar measured at the injector rail check to see if the plugsare getting wet indicating fuel is flowing – if not and the injectors are openingthen there’s a problem with the pump or the filter or even the pressureregulator
Customer: replied 2 years ago.
Hi Matt it's a 2009 1.6 tdi vw golf it's not a petrol
Expert:  Matt replied 2 years ago.
whoops OK my comment about the oil pressure still applies but as for the rest of itI'd check thatyou're getting full power to the glow-plugs, they pull a lot of current so takecare when checking but see if the relay is clicking when the ignition is turnedon first and also check the fuse if this is OK check to see if the engine earthstrap is also OK.If the plugs haven't been changed in the last 20K then they may have to bereplaced.You can test theglow-plugs with a multimeter by measuring the resistance across the plug (between the power connection and the body) it should be around 4-8ohms if itstending to infinity / open circuit the plug is faulty or by using a clip on current clamp, either on the supplywire to glow plugs or onto engine earth, with glow plug light on you should see15-20amps for each glow plug fitted, 4 cylinders would be approximately60-80amps.Also if its not injecting at all then check the connections to the crankshaft sensor, unplug it and check for corroded contacts and broken wiring, and consider fitting a new sensor - do the same for the cam position sensorIf the EGR valve is stuck open then this too can effect starting so try disconnecting it to see ifthis helps or changes anything Could also be an injector leaking fuel back through the overspill pipe, so not getting enough fuel pressure to tell ECU to fire the injectors, this is trickier to find and you’ll need the garage to do a ‘run back’ test to identify which one is the issueLastly it’s also worth considering fitting a new fuel filter as if only slightly blocked thiscan lower fuel supply pressure and choke the main pump, the pump will be more sensitive to this when its cold as diesel thickens considerably with low temperatures.
Customer: replied 2 years ago.
Ok Matt I will check tomorrow thanks for the help
Expert:  Matt replied 2 years ago.
no problem
Customer: replied 2 years ago.
Just so you know Matt it was the ECG valve a common fault for 2009. 2012 VW golf tdi £1100 worth
Expert:  Matt replied 1 year ago.
Hello Ok I take it you mean the EGR valve? as that the part I mentioned may be stuck? still glad you got it sorted Bear in mind that the site takes a deposit from you at the beginning and this is held by the site until you rate my answer at which point the cash is split between the site and the expert. so if my answers have been helpful please rate my answer.
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