Low MPG Still!

[col1695]

Hi,

I had the Lambda sensor on my 172 replaced on thursday as it was drinking fuel like it was going out of fashion, it seemed to be ok for a few days but now my mpg has gone really low down again, any ideas on what else could be wrong?

I have done the basic diagnostics program that comes with the car and it pops up with the Letters T and H as faults, i know T is an injector fault, could this be part of the problem?

Thanks for the help!

 

[john182rs]

Did you use a genuine renault one, i used a ngk one aswell as a bosch an it was alot lower than when i stuck one in from ktec/renault.

 

[col1695]

to be honest im not sure, had it done at a garage and didnt think to check which one they were using :s

 

[john182rs]

Stick your head under the car and have a look, I found my NGK and Bosch ones to have a short black covering on the wire from the sensor and the one closer to the engine was touching the pipe and had melted through.
The Renault one, even though that is Bosch aswell or so im told, has a slightly longer wire cover and came with a clip to hold it away from the exhaust.

 

[kerry-w]

Got same problem here on my 1.2, the Injection system light comes up on the dash when I start it. So I assume we will have a pretty similar problem, ive also had the lamba sensor replaced on mine about 3 weeks ago so im pretty sure it's not that.

Although I did have a new center pipe and backbox fitted so maybe thats done something with the lambda sensor?

What else could be the problem?

 

[john182rs]

Sorry Kerry, i can not help you with a 1.2. I only had a 1.4 for a year before the 182 came along.

 

[kerry-w]

Sorry Kerry, i can not help you with a 1.2. I only had a 1.4 for a year before the 182 came along.

Id have thought it would be around the same thing causing the problem for both of us, had a google of it and it said something about the coil pack and spark leads :S I can replace them on mine and see how it goes I suppose.

Ill get the lambda sensor looked at too, another garage changed the handbreak cables so could it be possible they could have tampered with anything by mistake?

 

[john182rs]

If your in proper deep south wales have a drive over to ktec and ask them to look at it one day, they will be able to source the problem for you and will more then likely have the parts on site too.
Cardiff to ktec is 108 miles, i know that sounds alot but i do travel from north nottingham to ktec and its more than 220 miles one way.

 

[Dave..]

What MPG are you getting? Might just be high hopes and not a problem?

 

[kerry-w]

If your in proper deep south wales have a drive over to ktec and ask them to look at it one day, they will be able to source the problem for you and will more then likely have the parts on site too.
Cardiff to ktec is 108 miles, i know that sounds alot but i do travel from north nottingham to ktec and its more than 220 miles one way.

Im taking it down to G-Tec in Carmathen when I have some time to see what they can say about it ill check distance to get to Ktec though, will be around 200miles for me too I think though, its 80miles to Cardiff from here.

What MPG are you getting? Might just be high hopes and not a problem?

Im getting 110 ish miles from 20litres, very poor compared to before

 

[col1695]

well mine was gettin 30 before, it went down to 24 so i had the lambda sensor changed and went back up for a few days, nows its back down to about 26, its got a ktec stealth exhaust and its been de-cat too but the MPG should still be higher than 26 :S

 

[kerry-w]

well mine was gettin 30 before, it went down to 24 so i had the lambda sensor changed and went back up for a few days, nows its back down to about 26, its got a ktec stealth exhaust and its been de-cat too but the MPG should still be higher than 26 :S

When you turn the ignition on does the Injecion system light come on for a few seconds? Its a square box with 2 wavy lines going through it