twingo gt flat spot jerky sensor?

[eddierogers]

Hi all,
I'm posting this for a bit of advice I've got a twingo gt it's got 85, 000 serviced regularly, I've been having problems with a flat spot in 1st and 2nd gears coupled with it being a bit jerky its more noticeable when cold but does do it most of the time mpg seems poor to me only getting 300 to a tank of motorway miles. I changed the coolant temperature sensor due to getting a fault code. I'm not getting any fault codes up now but the problem is still there I'm leaning towards it being an o2 sensor have any of you guys got a more likely sensor that maybe at fault? just don't want to start changing parts on a hunch. Cheers in advance eddie

 

[oscar]

hi eddie, somewhere just over 300 miles per tank in a gt seems about right. in real world driving that's around 40 mpg and anywhere from the high late thirties to mid forties in economy is what we all get in the real world in our gt's. deffinately sounds like a defective lambda sensor as you said it's very hesitant on throttle in the low gears, this would be a lot more noticeable on cold starts especially when the air : fuel ratio is above lambda-1. what you'll need to do is take out the sensor do a voltage test on it. if you get values of 0,1 - 0,5 you can rule the sensors out as they are working fine. if they are noticeably above that, what they are doing is telling the ecu that the mixture has too much oxygen when it doesn't and it is dumping more fuel in to compensate which will result in a loss of power on throttle and a higher consumption

 

[waitey]

If it is lurching about when cold its a trait some twingos seem to have and is referred to as kangerooing, its usually nothing to do with a lambda sensor as it may be trying to get the CAT up to temp as fast as possible.

Renault have released a revised ECU map to fix this issue.

 

[eddierogers]

Thanks for the replies, I've always noticed that its a bit jerky since owning it (about a year) but its more noticable now. I'll let you know how testing the lambda goes. Maybe its just me being a hypochondriac?
Cheers again.

 

[Ash331]

Mine dose this I just thought this was the car when you try setting off normally :/

 

[Noesph]

Yeah, same here. I find mine to be jumpy for the first 2 minutes or so. I think the most I got out of a tank on mine is about 230 miles (well on the last orange square), but that's mainly town driving. Personally it's a bit bad when my old 13 year old 8v 1.1 106 could do 450 miles from a 45 litre tank, and could just about do 500 miles to a tank on a motorway trip.

 

[MovingShadow]

Depending on how I drive, I average get 310 before the needle hits the red.

Best I got is 372 miles on a steady road trip to te UK.

 

[user 980]

Even with short trips round town you should be getting more than 230 miles especially in a GT :s

 

[Noesph]

I know. I did a full service (oil, oil filter, air filter, spark plugs, cabin filter - all renault parts.), new tyres (I check the pressure about once a month, it never really drops more than 0.1 bar from the recommended pressure). I guess something is wrong with one of the sensors, but there are no fault codes, and it seems to run ok as well.

Tank doesn't help either, sometimes I fill it 2 clicks at the pump, go a few miles down the road and I lose a square.

 

[maggi200]

Start pulling em then :lol:

Are the o2 sensors a pain to get to?

 

[singlespeed]

I don't think the Lambda sensors are used during warm up, or wide open throttle at higher revs.

 

[oscar]

I don't think the Lambda sensors are used during warm up, or wide open throttle at higher revs.

i can't remember if they are HOS sensors, i suppose eddie will need to let us know this one by telling us how many wires there are on the oxygen sensor! if it is HOS, they will take no longer than 10 seconds to warm up and are usually half warmed up by the time your warning lights go out and you turn the key to crank the engine

 

[maggi200]

I don't think the Lambda sensors are used during warm up, or wide open throttle at higher revs.

I'll be honest I didn't read the post(s) so no idea when it was doing what

 

[Noesph]

They look to be a ******* to get at. In the haynes manual (for the clio) they reckon the catalytic converter has to be removed with the sensor as there isn't room to take it off separately.

 

[singlespeed]

I read that^^^ as:-
remove air filter and heat shields
Undo the connectors
Undo some clips
Remove sensors.

Cant see the cat comming out

 

[oscar]

guys you don't need to remove anything to test your sensors. simply unplug the wiring harness, red / positive multimeter terminal goes into the middle of the three holes on the plug / clip and then earth it. make sure the engines been ran and warmed up before you do this, turn it on and take readings over 20-30 seconds. it should fluctuate between around 0,5 volts but 0,2 - 0,8 or 0,9 is acceptable. if it reads much higher than 0,8/9 Volts or shows nothing at all basically bin it! there may be nothing wrong with it, but it's better to rule it out before you have a guess!

 

[Noesph]

I read that^^^ as:-
remove air filter and heat shields
Undo the connectors
Undo some clips
Remove sensors.

Cant see the cat comming out

That's from the renault workshop manual, this is from haynes. The cat is behind the engine, making it hard to get to.



I will test it with a multimeter at the weekend.

 

[waitey]

I read that^^^ as:-
remove air filter and heat shields
Undo the connectors
Undo some clips
Remove sensors.

Cant see the cat comming out

That's from the renault workshop manual, this is from haynes. The cat is behind the engine, making it hard to get to.



I will test it with a multimeter at the weekend.

Does that Haynes manual actually have anything in common with the twingo?

 

[oscar]

sorry guys i'm not too sure what you're meaning by highlighting that haynes section? you are testing the ressistance and voltage in the wiring which doesn't require removal of anything. it only requires you to remove a clip, you are testing the resistance of the sensor itself and if the results appear to be within tolerance you then will move on to testing the voltage from the ecu to the sensor. essentially checking resistance to find if the sensor is faulty or working and then confirming that the ecu is sending the correct voltages to the sensor itself, if both are okay then that's that ruled out. you are removing the clip wiring to the sensor, not the sensor itself! resistance check on the wiring on the sensor itself. voltage check on the other clip coming from the ecu. you'll see the oxygen sensor straight away from

 

[Noesph]

It's for the clio 3. But it has the 1.2 (d4f) , tce (d4ft) and 1.6 engines (K4M) in there.

Anyway, Sensor 1 (pre cat) jumps from around 0.1 to 0.75 about every second at idle (say plus or minus 0.05v). Sensor 2 (after cat) is always at 0.46v.

One thing I though was a weird that on the obd 2 reader, the short term fuel trim is -100%