Author Topic: Coolant temp sensor probs  (Read 1951 times)

Offline stace110

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Coolant temp sensor probs
« on: 15 November 2012, 16:33 »
Hi all, iv'e just replaced the CTS and disconnected the battery to clear the code .....mpg has risen which is a good thing But .....now i have a bit of a lumpy idle ,like if i come to a junction it bounces then its fine ....Any ideas ?
1999 AGU, sitting on Dotz 18's,forge 008p, r32 side skirts. satin silver....more to come

Offline topher

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Re: Coolant temp sensor probs
« Reply #1 on: 15 November 2012, 16:36 »
could be a slight vacuum leak somewhere but a throttlebody clean is a good place to start. If you do a search you'll find a guide

Offline stace110

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Re: Coolant temp sensor probs
« Reply #2 on: 15 November 2012, 16:50 »
The thing is ...it didnt do it until i changed the sensor and reset the ecu ....?
1999 AGU, sitting on Dotz 18's,forge 008p, r32 side skirts. satin silver....more to come

Offline stace110

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Re: Coolant temp sensor probs
« Reply #3 on: 15 November 2012, 16:53 »
Also while im at it lol ..For some reason i have no power on the obd port i have to use a self powered code reader .....and i cant use my friends vag-com .....agu lump ....?
1999 AGU, sitting on Dotz 18's,forge 008p, r32 side skirts. satin silver....more to come

Offline topher

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Re: Coolant temp sensor probs
« Reply #4 on: 15 November 2012, 16:56 »
fuel trims get reset when you erase fault codes, and a non-reading temp sender will have been making your ECU do strange things with the fuelling.

Also while im at it lol ..For some reason i have no power on the obd port i have to use a self powered code reader .....and i cant use my friends vag-com .....agu lump ....?
yeah AGU's are pre-OBD2 compliance so they don't have the 12v there, a genuine vagcom will work on it the ebay copies tend not to work too great on the AGU.

Offline stace110

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Re: Coolant temp sensor probs
« Reply #5 on: 15 November 2012, 17:00 »
oh and any idea of the part number for the hose under the inlet manifold that goes to the pcv valve ....mine is split and knackered , Many thanks for the quick responce and answers .
« Last Edit: 15 November 2012, 17:03 by stace110 »
1999 AGU, sitting on Dotz 18's,forge 008p, r32 side skirts. satin silver....more to come

Offline Wazzzer

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Re: Coolant temp sensor probs
« Reply #6 on: 15 November 2012, 18:15 »
That'll be your idle problem then


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Offline stace110

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Re: Coolant temp sensor probs
« Reply #7 on: 15 November 2012, 18:28 »
No ive bodged another pipe on for the moment but did that about a week ago so its not that ....
1999 AGU, sitting on Dotz 18's,forge 008p, r32 side skirts. satin silver....more to come

Offline topher

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Re: Coolant temp sensor probs
« Reply #8 on: 15 November 2012, 18:32 »
06A 103 221 C for the AGU. We usually keep a couple on the shelf they're very prone to splitting

Offline stace110

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Re: Coolant temp sensor probs
« Reply #9 on: 15 November 2012, 18:46 »
Price ?
1999 AGU, sitting on Dotz 18's,forge 008p, r32 side skirts. satin silver....more to come