Starting or idle problem

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BusterDAN
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Starting or idle problem

Post by BusterDAN »

Hi all, new to the forum and I have just bought a 97 1.6 GL 6n generall y speaking it is in very good condition considering it's age.

There are a few issues though the most improtant one being that the car starts on the key first time... but promptly dies... try again... same thing... and again... again.

After about five attempts the car splutters a fair bit but by keeping the revs around 3-4k rpm the engine is able to stay running. After about 30 seconds like this the car idles a bit lumpy but wont stall... If the car is warm then no problem.... it's just when the car has been left a few hours. Unfortunately this doesn't really bode well for the winter.

To recap the engine fires first time on the starter with a twist of the key... no problems there, but it wont idle at first. I'm not sure this is specifically a cold weather thing but when the engine is warm the idle speed is stable when first started, for example this afternoon:-

For example today... on the key only....

Start... immediately 1k rpm then stall
Start again, same
Again idle just over 1k then down to 500rpm.... holding on.... then stall
Again as above..... hanging in there at 500k then stall
Finally start 1k rpm, lumpy but then stabilised at just under 1k rpm

This was over a time frame of about 20 seconds I suppose.

When I test drove the car I forgot to see if the car was already warm... I reckon I've been a bit misled unfortunately however once the car gets running it is fine so if I can crack this idle issue I'll be happy.

Thanks for your help.
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NOZ
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Re: Starting or idle problem

Post by NOZ »

Got misled similary to you when I first got mine 3 years ago :? Learnt my lesson though.

Anyway, if you can then get the car diagnosed, preferably using VAGCOM. Hopefully it would show where the problem lies.

Other then that you hsould give your car a fully service including the water and fuel pump maybe if the cambelt needs doing.

Check the Distributor, leads and plugs. take the airbox off and check the throttle body isn't dirty. Use some carb cleaner on a rag to clean the TB and reposition correctly. If you can get VAGCOM them use it to realign the TB.

Other problems could be that the Temp sendor isn't working correctly when the car is cold. I'm sure there's other things people will tell you to check that i've missed out.

Good luck.
BusterDAN
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Re: Starting or idle problem

Post by BusterDAN »

I just called the seller and said "whats the story with the non starting"... of course he denied it saying it started first time when I tried it and that it wasn't warm when I did. That he didn't know what I was talking about and it was sold in good faith.... I know one thing this problem hasn't just started happening over night!!

I'm going to try the temperature sensor in the first instance... then go down the throttle body route, thanks.
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NOZ
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Re: Starting or idle problem

Post by NOZ »

Temp senders around £20odd but the TB is cheaper to clean and check.
BusterDAN
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Re: Starting or idle problem

Post by BusterDAN »

Got a new Temperature Sensor today and I think it has done the trick... it looks like the old one was the wrong type and therefore the owner used PTFE tape to seal it! :shock: of course it didn't and clearly there has been coolant loss over the years. The care was cold and started first time, but tonight or tomorrow morning will be the real test when it is much colder.

Thanks.
BusterDAN
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Re: Starting or idle problem

Post by BusterDAN »

Yep the new sensor has definitely done the trick so I am really pleased.
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