Vauxhall Astra G Petrol - Vauxhall Astra 1.8 16v - Throttle Sensor & ECU..

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Sat 20 Aug 2011 15:31
Vauxhall Astra G Petrol - Vauxhall Astra 1.8 16v - Throttle Sensor & ECU.. - SomeoneElse

Hello guys, I need fast and honest help with my 2001 Vauxhall Astra MK4 1.8 16v.

Symptoms include Engine Management light appearing. Slight reduced power. Pulsing acceleration when ignition is turned on then eventually balances out and idles normally. Delayed acceleration and very sluggish.

I ran the pedal test on my car to determine the fault codes. These were the results..

Error code 1555: Throttle Position Sensor Error.

Error code 1525: Limp Home Error.

Error code 1550: Reduction of power to the engine.

I took my car to a local garage and wiped the codes. 2 hours after this was done, Error code 1555 showed again.. 3 days later these same 3 error codes appeared.

I am completely fed up of local garages giving me various quotes for many different problems that 'could' be wrong with it. So, my aim is to fix the problem as soon as possible and in the cheapest way possible. Any help would be very much appreciated. Thank you in advance.

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Sat 20 Aug 2011 16:12
Vauxhall Astra G Petrol - Vauxhall Astra 1.8 16v - Throttle Sensor & ECU.. - injection doc

The 2nd and 3rd fault code are triggured by the first.

I would recommend making sure the whole throttle body is cleaned first and that the throttle flap can return fully shut ! dirty throttle body may prevent this , thus triggering off TPS fault. ECU's are also common problem on these causing similar issues.

Also make sure there are no air leaks however small. Hint to clean throttle body is with can of carburettor cleaner and a tooth brush, open throttle fully and clean both sides of throttle body untill spotless.

My other port of call to check would be to make sure the car is fitted with vauxhall plugs ! I can assure you I have had so many managment problems in the past caused by what we call in the trade " Electrical noise " caused by High resistance plugs ! Champion are a good cause !

Edited by injection doc on 20/08/2011 at 16:15

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Sat 20 Aug 2011 16:30
Vauxhall Astra G Petrol - Vauxhall Astra 1.8 16v - Throttle Sensor & ECU.. - SomeoneElse

Thank you for your fast feedback. I will try this and inform you of any updates. Thank you.

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Sat 20 Aug 2011 22:33
Vauxhall Astra G Petrol - Vauxhall Astra 1.8 16v - Throttle Sensor & ECU.. - RT

There is a reasonably well known problem with ECU wiring on many Vauxhalls caused by a combination of two things:-

1) The ECU is mounted on the engine so suffers from vibration which can lead to ECU pins solder joints failing.

2) All the sensors are earthed back through the ECU, not directly to earth

If it's an earth pin on the ECU which has failed, the affected sensor can have it's earth cable diverted to go directly to earth.

If a number of sensors are affected in this way, the ECU can be reconditioned by specialists and get all the pins re-soldered.

Check out the Astra Owners Network website for more details - I'm hazy now as I sold my Astra in 2006.

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Sun 21 Aug 2011 14:33
Vauxhall Astra G Petrol - Vauxhall Astra 1.8 16v - Throttle Sensor & ECU.. - SomeoneElse

Thank you guys for your feedback. I dismantled the throttle body, and gave it a thorough clean using carb cleaner.. BINGO!.. The car now starts like a new car. It idles normally and doesnt pulse like it used to. Now I just touch the accelerator and im up to 40mph haha. I havent seen the engine management light yet and fingers crossed I dont. The error codes are still there, but im having them wiped off later today. You've probably just saved me around £500. Thank you very much for your help. God bless.

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Sun 21 Aug 2011 14:54
Vauxhall Astra G Petrol - Vauxhall Astra 1.8 16v - Throttle Sensor & ECU.. - injection doc

well done and thanks for the feed back, I'm fairly sure you will find its fixed.

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