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Matt, Mechanical Engineer
Category: Vauxhall
Satisfied Customers: 24150
Experience:  BEng hons Mech engineering, in auto industry 22 years
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I have a o8 astra 1.7cdti, it starts from cold but takes a

Customer Question

Hi i have a o8 astra 1.7cdti, it starts from cold but takes a few turns, gets hotvand takes longer to start, now wont start at all as its hot,
Had a service and all filters changed and glow plugs redone,
And also diagnostics check all came back with one fault saying a glow plug was naff, but the problems worse now?
Theresno lights on the dash,
I drove it 200 mile otherday and after 130 mile it went i to sort of limpish mode, wouldnt rev above 3000 and no power when foot down on acelorater.
Drove another long journey and all ok,
In need of advice?
Submitted: 6 months ago.
Category: Vauxhall
Expert:  Matt replied 6 months ago.


I'd check that you're getting full power to the glow-plugs, they pull a lot of current so take care when checking but see if the relay is clicking when the ignition is turned on first and also check the fuse if this is OK check to see if the engine earth strap is also OK.

You can test the glow-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 its tending to infinity / open circuit the plug is faulty or by using a clip on current clamp, either on the supply wire to glow plugs or onto engine earth, with glow plug light on you should see 15-20amps for each glow plug fitted, 4 cylinders would be approximately 60-80amps.
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 sensor
If the EGR valve is stuck open then this too can effect starting so try disconnecting it to see if this 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 issue
you can also do a reasonable run-back test yourself by disconnecting the electrical plug on the injectors and the downstream pipe of the leak off, crank the engine over and if you see a noticable difference if the flow in the leak off then that the likely problem injector.
Lastly it’s also worth considering fitting a new fuel filter as if only slightly blocked this can lower fuel supply pressure and choke the main pump,

Expert:  Matt replied 6 months ago.

My goal is to give you the best advice that I can and I hope that I've helped today. Please remember to rate my service by selecting from the 5 stars at the top of the screen before you leave. If you need more help, use the reply box to let me know.
If you're not pleased, also let me know because rating bad does not result in a refund, there are better options. Rating now will not close this post nor prevent further replies
Thanks Matt

Customer: replied 6 months ago.
Hi matt,
Thank u for the reply,
I had the glow plugs and fuel filter changed a month ago, ive managed to get the car started again, im not a mechanic but got a rough idea, im going to book it into a vauxhall garage,
I will check the glow plug fuse first��
Expert:  Matt replied 6 months ago.


if my advice was helpful please consider rating my advice appropiately