1.8 making putt-putt noises on idle

DALE_AVANT

DALE_AVANT

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Hi all.

Our 1.8 non-turbo is making putt-putt noises on idle, and is hesitant when pressing the accelerator from 1-2k revs.

It is used irregularly so also turned over before starting but that is just the battery I am sure.

Any ideas at this stage?
 
Any fault codes, could be a coilpack there prone to failure
 
Haven't had it scanned yet, will get it to the mechanic
 
Get yourself a cheap code reader of eBay, about £12, save yourself a fortune on getting it scanned at a garage.
 
Also, there is a blow in the exhaust at the engine end, could this be throwing out the lambda sensor readings?
 
Update time.

Fully serviced with new oil and filter, air filter, fuel filter, spark plugs.

At the same time as the service, mechanic checked car over and scanned, no faults on VAGCOM, and no presence of a blow on the exhaust.

The band and mount on the boxes were corroded but this shouldn't cause this issue.

Mechanic mentioned that it could be the MAF?
 
Will give the MAF a clean with electrical cleaner tomorrow.

Is the throttle body easy to access and clean? Carb cleaner?
 
Yes very easy, do a search on here for all the info you need to do the job, it's well worth the effort.
 
Cheers A3T, looks simple enough. If I ensure the butterfly is where I found it will there be any problems with alignment etc?

Also, what tamper torx bit do I need to remove the two bolts on the MAF sensor?
 
For those that find this thread, you need a TS25 5-point tamper-proof torx bit (star shape with a pin in the middle) to remove the 2 bolts attaching the MAF sensor.

So I have cleaned the MAF but the original issue still remains. Time to clean the throttle body, does the alignment reset itself after cleaning?
 
What is the best way to remove and clean the throttle body? I did not realise that it was also a cable-type throttle
 
audi upgrades
Disconnect battery
Undo 4 allen bolts holding Throttle body onto inlet manifold
Remove boost pipe from throttle body (jubilee clip usually)
Remove vac hose off top of throttle body
Clean throttle body taking care not to get cleaner into electrical part of throttle body (if DBW)
Refit in reverse order with new gasket (pennies from dealer or TPS) and connect battery
Carry out vag com reset of throttle body using guide below (if DBW)
http://www.ross-tech.com/vag-com/cars/throttlebody.html

Job done
 
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Cheers Scotty. How do I disconnect the actual throttle cable (it's an AGN non-turbo, body is to the top right of the engine bay I think)
 
No worries mate, I can't find much about it anywhere, all pics are the 1.8T
 
I had a similar put-put noise on my S3 when idling. took me ages to figure out what it was, turns out it was the heater/air-con whenever it was switched on there was a put-put faint noise, thought it was an engine problem but it was just this. probably not the problem you have but worth a try
 
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Cheers Donfresh, however this affects idle and rough revs under 2000k
 
Have you tried disconnecting the maf electrically to see if it idles/runs better, I know you've cleaned it but that may not solve the issue if it's out of calibration.


Steve
 
Thread resurrection, the car has started doing the same thing, 10 months later :wtf:

Rough idle, rough, hesitant revs, and temp guage takes forever to get to 90.

Earlier in the year we seemed to have solved the problem by replacing the HT leads, cleaning the MAF and a full service with new oil and filter, air filter, fuel filter, spark plugs.

Any thoughts folks, we need to this car to be running right
 
Thermostat for sure. Common culprit which stops your engine getting to 90 degs. Get a genuine new thermostat on there from an Audi dealer, reset your codes and then rescan after a fresh drive to see what's left.

The thermostat is a revised part and the new one should be green in colour (well it is on the S3 anyway). Let us know how you get on.
 
Is this also called the coolant temp sensor?

Is it an easy job on the drive or one for the ramps?
 
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No that is something different and I think it's located in the expansion tank - or perhaps that's the fluid level sensor. I don't recall exactly. Anyway, some people replace both when they have temp problems). The thermostat can be a bit of a pig to get to but is do-able for the DIY mechanic.
 
Good stuff, thanks.

Is there anything else it could likely be?
 
Will take this to a garage tomorrow, any more thought before I do?
 
Just to clear things up a little, this spluttering and rough running seems to be a cold weather issue.

Which specific sensors need replacing to potentially cure this? Thermostat and temp sensor?
 
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By way of removing one thing at a time, is it worth me starting by replacing the MAF as it's an easy job? Would a part from ECP be suitable?
 
OK thank you.

Am I right in thinking there is an air temp sensor AND a MAF (air flow sensor)?
 
*UPDATE

Car was scanned again at a VAG specialist and no codes.

I bought a new MAF and changed it over. Car seemed to be running normally which was great. Had a slight stutter under heavy pedal/4k+ revs but all in all an improvement for sure.

Started the car today, idled at 1.2k - 1.4k revs then started running rough again as before, basically undrivable.

Any more thoughts please?

On a side note, I checked the fuses over and fuses 24 and 25 had totally melted. Replaced them with a new 20A and 25A as the book states. Could these be related? They are for the 'wiper system/washer pump' and 'heater blower/air conditioner'. The strange thing is that these were working??
 
you did a "full service" a year ago and it resolved the issue why not simply do another full service?

I would put your old MAF back on - unless the replacement you got was a posh bosch one as the cheap ebay Chinese ones onlt seem to last for a few days, weeks etc.

weird that your main fuses had melted but not fused?
 
Along with the coil pack/spark plus/ignition leads/MAF/thermostat/engine temp sensor last year, it has been serviced again with new oil/oil filter/fuel filter, and it seems to have solved the issues. The throttle body was also given a quick clean.

Thanks for the help folks
 
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