Author Topic: low and lumpy idle/stalling when hot  (Read 2364 times)

Offline rowlers

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low and lumpy idle/stalling when hot
« on: 03 May 2005, 18:59 »
Any body got any suggestions as to why my 1990 16v, could be spluttering when hot?? It starts and runs great from clod, and even when only just warmed up. When the engine is hot though (getting worse now weather is warming up!) it start  as if its misfiring, then with a few blips of throtlle it even out and runs great above 1000rpm. However when I lift off throttle approacing a junction or what ever, it idels down to about 400rpm, on the verge of cutting out - it oftens does!

Its got new plugs, leads, dizzy cap and roter. The air cleaner and air flow meter has been cleaned out. The warm air flap "flaps" easily. Any suggestions???


I'm guessing its a temp sensor or something but I'm not a mechanic!! Help!!


Cheers


Rowlers

Offline Gambit

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Re: low and lumpy idle/stalling when hot
« Reply #1 on: 04 May 2005, 09:46 »
sounds like the hall sender within the dizzy itself. the hall sender is the wee electrical connector you see coming out of the dizzy. its breaks down when the car is really warm, i.e been sitting stationary in traffic etc

to replace it you need to remove the actual dizzy then split it down. to split it down you need to remove the pin from the rear of the dizzy

make sure you mark the centre line on the dizzy against the block, otherwise your timing will be screwed when you go to refit it.

alternativily buy a whole new dizzy if you dont fancy attempting to replace it

Offline AudiA8Quattro

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Re: low and lumpy idle/stalling when hot
« Reply #2 on: 04 May 2005, 09:53 »
check your fuel/air mixture.
FOR DIY GUIDES GO TO <br>www.volkswagenaudi.co.uk<br/>BRAKES, SUSPENSION, CV JOINTS

Offline rowlers

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Re: low and lumpy idle/stalling when hot
« Reply #3 on: 04 May 2005, 18:08 »
Cheers for replies, the air/fuel mixture is OK.

It does start when you say - for example sitting in stationary traffic. Is it a big job? Sounds complicated!!! How much do the parts cost???
Does the haynes/bentley manual cover this job??


Thanks


rowlers

Offline Gambit

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Re: low and lumpy idle/stalling when hot
« Reply #4 on: 05 May 2005, 10:35 »
no its not particulary complicated. im not sure if haynes would cover it though

ask stuart from ECP of here for the price for a hall sender, they are £31+vat from EuroCar Parts but he will get you discount as your a member of the site

also, new distributor is £68+vat, with a £60 surcharge on return of your old dizzy to ECP

new dizzy is the easiest/least hassle way to fix it if youdont feel confident breaking your existing dizzy down to replace the hall sender

Offline rowlers

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Re: low and lumpy idle/stalling when hot
« Reply #5 on: 05 May 2005, 16:59 »
Cheers,
I'll order the HSU, and have a go at replacing it was quoted £108 from VW for the HSU!!!

How do I get the discount from ECP?? Can I order online or do I have to phone and ask for Stuart (second Name?)

Thanks Again!

Offline Gambit

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Re: low and lumpy idle/stalling when hot
« Reply #6 on: 05 May 2005, 17:03 »

Offline rowlers

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Re: low and lumpy idle/stalling when hot
« Reply #7 on: 05 May 2005, 17:58 »
cheers gambit

Offline rowlers

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Re: low and lumpy idle/stalling when hot
« Reply #8 on: 17 May 2005, 17:42 »
Just a thought - does the hall sender have anything to do with the cooling? Like a temp sender or something?? The coolant needle never gets out of the white, except when statiomery in traffic and only then a little.
A mate reckons the thermostat is stuck open so the car never gets hot. oil temp reading is normally about 70 to 85.

cheers again you knowledgable ones!

Offline wellfan

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Re: low and lumpy idle/stalling when hot
« Reply #9 on: 17 May 2005, 17:58 »
Your thermostat is definitely stuck open (I had exact same symptoms,ie. low oil temp reading and low water temp reading), however, I am not sure if that alone would account for the problems you are facing. I would try to replace the thermostat first and then see where you are with the problem.