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Daz8161

Daz
Mar 9, 2005
587
0
Belfast
Ok guys, I really need your help, I tried a search but didnt find a solution. My car is a 1.6 petrol.

The situation: Previously the 'Excessive pollution' light had been coming on and off intermittently but the car seemed to drive unaffected. After a month or so I stopped at traffic lights after a 30mins motorway drive and the car started idling really rough. Pretty much like the car was trying its best to stop itself from stalling. The rev needle was flucating up and down as this was happening. When I got to my destination i turned the engine off and after about 10 mins I went back to the car to try and start the car, it wouldnt start. It turned over but wouldnt start. I had to bump start the car to get home. The car ran fine on the way home apart from the rough idling. The car started fine the next day and I took the car to the garage. The spark plugs were changed as they were 'black and carboned up' and I was told the car started fine. When I got the car back after a 10 min drive the car did the same thing as before (rough idle then wouldnt start for 40 mins). It is now currently at another garage and has sat there for 2 weeks.

Initially I was told it could be a faulty relay or broken wire as the ecu wasnt getting a reading. When the relays were checked as fine the crankshaft sensor was checked and was apparently ok. A fault on the EGR was found and was disconnected and still doesnt start when disconnected. A fuel pressure gauge was then put in line and when the 2 times the car wouldnt start the pressure read 6 & 4 barr and also the fuel pressure was very slow to drop down after the car had been sitting parked up. This led the mechanic to think there was a faulty fuel pressure regulating value. I asked him to take the car over the weekend and see if it would give a high reading again if the car wouldnt start again. This time the pressure read 2.5 barr when it didnt start.. The mechanic now says its not the fuel pressure regulating valve.

Since then the car has been sitting at the garage for 2 weeks I really dont know how to fix this and seems to me the mechanic doesnt either. Any ideas guys? Your help and comments are greatly appreciated!



Person to come up with the solution gets an ice cold beer!
 
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Hot starting is in-line with the coolant temperature sensor not working, they fail and not allow the car to start till it cools down.
 
Hot starting is in-line with the coolant temperature sensor not working, they fail and not allow the car to start till it cools down.

Thanks Lee, would this be the issue causing the car to idle like it is about to cut out too? The garage have started the car a few times, letting the engine warm up on idle and yet starts ok. It seems to be only when driven for a while does it start to idle rough and refuse to start?
 
One more thing, the mechanic has said there hasnt been a fault logged on the coolant temperature sensor as it would aparently go to a default reading of -40C if there was anything wrong with it? However come to think of it the garage I had it at before who changed the spark plugs did mention a coolant temperature fault...
 
Just to complete this the problem was a sticking EGR valve and faulty lambda sensor. EGR was cleaned and lambda sensor was replaced, also changed the coolant temperature sensor as a precaution. everything worked fine after.