Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold

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Thu 12 Dec 2013 06:20
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - matt2324

Hi,

I have bought a Vauxhall Vectra 1.8 (2000) with a x18xe1 engine.

Much of the time idling is very rough and occsionally the car stalls when idle. Lights will dim and RPM will jump around between 300 and 1200. Engine management light is on. Strong petrol smell when idle inside the car.

I also took it for an 80 mile motorway trip yesterday and the temperature sensor was permanently in the blue, it did move up and down within the blue slightly but never above. Heaters blow slightly warm but not hot.

Does anyone know what could cause this? I've read plenty about sensors needing cleaning to solve the rough idle but can't find much about the cold temperature.

Many Thanks

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Thu 12 Dec 2013 07:37
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - The-Mechanic

I'd suggest instead of trawling the net reading about other people's faults that may or may not be relevant to yours, you get the car to garage, plugged in and the error code(s) read.

There are many causes of your type of fault and many sensors that could cause them so the best way to find out is narrow it down by proper diagnosis and not wasting time and money replacing parts that someone else, on an internet forum, with a similar fault said fixed theirs.

Low temp gauge readings could possibly be as simple as a faulty sender which in turn may be effecting the fuelling, causing the engine to run rich and over fuel hence the smell, poor running and EML being on. There again, it may be the thermostat sticking (a known problem on these engines) and a different fault causing the over fuelling which will need diagnosis by computer.

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Thu 12 Dec 2013 08:20
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - matt2324

Thanks for your advice, much appreciated.

I'm not very mechanical, however I notice a replacement sender is only a few quid and looks like an easy job so i'm going to replace it myself and if that doesn't help will get the codes read at a garage.

Cheers

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Thu 12 Dec 2013 09:14
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - matt2324

I managed to do the paperclip test and got the following three errors :

p0100 mass or volume air flow circuit malfunction

p0110 intake air temperature circuit malfunction

p0131 o2 sensor circuit low voltage (bank 1 sensor1)

But I don't have much of an idea as to what they mean

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Thu 12 Dec 2013 09:59
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - Collos25

They are faulty MAF sensor thats the sensor in the air intake,

a faulty sensor in your exhaust pipe you have a bank 1 and a bank 2 sensor one in the first first cat and one after it which is 1 or 2 I don#t know.

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Thu 12 Dec 2013 10:11
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - matt2324

I've dug deeper online and everything seems to point to an earthing problem causing sensors to misread, so i'm going to try the fix later and see how that goes

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Thu 12 Dec 2013 11:31
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - dieselnut

If the temp guage is in the blue & the heater output is low then almost certain to be the thermostat stuck open.

If you start the engine from cold, feel the top hose or top of the radiator after the engine has run at tickover for a few minutes. If they are starting to get hot the thermostat is stuck open. Will be causing poor fuel consumption as well so will be very cost effective to get it fixed.

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Thu 12 Dec 2013 11:49
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - RT

The Vauxhall X18XE1 (1.8 smallblock) engine does have a design issue - the ECU is bolted to the engine so suffers vibration and eventually fatique cracks occur in the soldered pin joints of the ECU. Each sensor is earthed through the ECU and it's the earth circuits that often seem to fail.

The proper cure is a new, or reconditioned, ECU but I have cured the problem on an Astra using the same engine by running an additional earth wire from the sensor - but it's tricky as the wires are very fine ones.

Edited by RT on 12/12/2013 at 11:51

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Fri 13 Dec 2013 00:07
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - matt2324

Thanks for all your help guys.

I did the ground fix and it cured the rev problem and the engine management light has gone off. I'l find out if the car temperature is heating up later when I take it for a longer journey.

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Fri 4 Mar 2016 20:16
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - david123443212000

change maf sensor. it's like magic lol had fueling ideling problem as well. cured 3 engine codes and rough ideling as well

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Sat 5 Mar 2016 15:20
Vectra 1.8 - Vectra 1.8 rough idle & temperature gauge cold - jc2

And the heater????

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