TheCrust
17-09-2009, 10:25 PM
Hi everyone - first post here!
My father-in-law has a 1998 / S-plate 1.4 16v Golf that has recently started to run really rough at idle.
The problem initially started - so he tells me - when the plastic covering on the camshaft sprockets shattered and ruined the belt, despite the whole kit being less than 2 years old.
He took the car back to the garage - a VAG specialist in Wakefield - who did the cambelt kit, and the guy replaced it saying "never seen that happen before".
Ever since, the car has had what can only be described as a lumpy idle - almost like it's hunting, or misfiring, and a soft irregular popping can be heard from the exhaust. The idle speed as indicated on the tacho can be seen to vary by about 50 - 100revs.
My father-in-law has been back and forth to this place who have had the car on the diagnostic machine and not found any faults but something is clearly not as it should - prior to this the engine was as smooth as you like with a rock-steady idle. They've checked, cleaned and changed a few bits but nothing seems to have had much effect.
From cold, the car starts on the button and idles fine for the first minute or two, then starts hunting. Driving on throttle - such as accelerating or high-speed cruise on the motorway - and it's fine.
Light throttle / low engine speed - such as tickling it along in fourth at thirty - and at idle when warm, and it is lumpy.
I couldn't tell you exactly what has been changed or checked exactly as I'm posting this up from memory and I can't get hold of the old fart - but from what I understand the following has been done:
- Compression tested. Results OK, consistent and within specification
- Plugs cleaned and gapped
- HT leads checked for breakdown and resistance, results OK.
- No faults apparently reported via onboard diagnostics
- Camshaft timing checked and confirmed OK.
I have a sneaking suspicion that the Lambda / HEGO sensor is to blame but but the garage state this has been checked and works - and the car passed its MOT last month in this state so it can't be too far out of whack....
They are at a loss to explain the problem (which doesn't suggest they are much of a VAG specialist!) and have suggested changing the throttle body assembly as a last resort.
So - over to you guys. What do you think? Is the 1400 engine known for poor idle problems? Anything that commonly gives up that could cause this?
If you need me to provide more info I will where I can but the car isn't here with me so it may take a few days.
Thanks in advance!
Jim
My father-in-law has a 1998 / S-plate 1.4 16v Golf that has recently started to run really rough at idle.
The problem initially started - so he tells me - when the plastic covering on the camshaft sprockets shattered and ruined the belt, despite the whole kit being less than 2 years old.
He took the car back to the garage - a VAG specialist in Wakefield - who did the cambelt kit, and the guy replaced it saying "never seen that happen before".
Ever since, the car has had what can only be described as a lumpy idle - almost like it's hunting, or misfiring, and a soft irregular popping can be heard from the exhaust. The idle speed as indicated on the tacho can be seen to vary by about 50 - 100revs.
My father-in-law has been back and forth to this place who have had the car on the diagnostic machine and not found any faults but something is clearly not as it should - prior to this the engine was as smooth as you like with a rock-steady idle. They've checked, cleaned and changed a few bits but nothing seems to have had much effect.
From cold, the car starts on the button and idles fine for the first minute or two, then starts hunting. Driving on throttle - such as accelerating or high-speed cruise on the motorway - and it's fine.
Light throttle / low engine speed - such as tickling it along in fourth at thirty - and at idle when warm, and it is lumpy.
I couldn't tell you exactly what has been changed or checked exactly as I'm posting this up from memory and I can't get hold of the old fart - but from what I understand the following has been done:
- Compression tested. Results OK, consistent and within specification
- Plugs cleaned and gapped
- HT leads checked for breakdown and resistance, results OK.
- No faults apparently reported via onboard diagnostics
- Camshaft timing checked and confirmed OK.
I have a sneaking suspicion that the Lambda / HEGO sensor is to blame but but the garage state this has been checked and works - and the car passed its MOT last month in this state so it can't be too far out of whack....
They are at a loss to explain the problem (which doesn't suggest they are much of a VAG specialist!) and have suggested changing the throttle body assembly as a last resort.
So - over to you guys. What do you think? Is the 1400 engine known for poor idle problems? Anything that commonly gives up that could cause this?
If you need me to provide more info I will where I can but the car isn't here with me so it may take a few days.
Thanks in advance!
Jim