Random power losses for first few mins of driving.

[blambert]

Had an eventful drive last night.

I set off (cold engine) and as I pulled out onto the road the car was struggling to get above 2.5k.. a little shuddery. Had my foot flat to the floor and nothing, the revs falling off slightly even. Then suddenly off we went at full throttle but then as I changed into second it struggled again and this time was struggling around 3000 but I kept it planted and slowly the revs built up and then kicked in and off we went.

Drove fine, then it did it again (warm engine), so I pulled over and sat for a bit. Lumpy, ill sounding idle, dipping to below 500 and nearly stalling (dash + headights dimmed as it nearly stalled). turned it off then 5 mins later though f**k it I'll give it another go as I had to get home.

It pulled away fine and I drove it at 80mph up the M23/M25/A217.. then pulled over in the BP garage cause I was busting for a piss. Got back in, orange light was on, it took one or two more turns to start than before... pulled out onto the road.

It did exactly the same thing (hot engine)... and then drove fine.

I stopped to pick up some shopping and when I got back in it took slightly longer to start again.. this time I waited and just put 50% throttle on... the revs nerbled around 1500/2000 and after about 30 seconds jumped up to 4000.

Pulled away and drove home 100% fine no problems.

I'm getting normal mpg (37@80). The car might be running a bit rough at idle but I did a 60 - 120mph pull on the M23 and it is definitely not low on power!

Thoughts?

 

[Blue Mez]

At first i thought it may of just been the usual cold start thingy but sound like something else. Fuel filter maybe? you tried filling it up with fuel to the max and giving it a good hammering? similar thing happened to me in my corsa 1.8 and that cured it.

 

[Triki]

Ahhhh mine does that every morning. Currently with added pops and bangs, depending on how it feels.

I am hoping the up stream oxy sensor is the issue. As i have replaced mine today, so i will let you know tomorrow.

 

[Dunn]

maybe clean TDC sensor and change plugs

or get fault reader on as lambda can cause similar issues

 

[Blue Mez]

Ahhhh mine does that every morning. Currently with added pops and bangs, depending on how it feels.

I am hoping the up stream oxy sensor is the issue. As i have replaced mine today, so i will let you know tomorrow.

You have the normal cold start problem, nothing to worry about apparently

 

[Cookson]

Lambda

 

[sophiesdad]

as already said probably lambda sensor.(upstream sensor)
it has a heating element in it to aid emission regulation from cold.
this is more common fault than the actual reading element of the lambda

 

[Triki]

Well mine is a million times better this morning.
It honestly drives so much better, none of the holding back from cold etc that i have had for months. And idle is much better when warm.

I think it would be worth you trying an oxy sensor

 

[blambert]

Cheers guys, I'm gonna get the code read and then change whatever it says.

Sat in it now warming it up andce watched the mpg drop from 36.4 to 35.7 at idle!

Anyone know of somewhere near KT5 that can read codes cheaper than Renault? Cheers

 

[Addicted]

just to confirm without a thread hijack, pops & bangs from cold is normal then? i've noticed it on mine and told it was normal by a friend, just wanting to confirm

 

[blambert]

I’d say no its not normal.

Just got in the car to drive back from asda and we had the same problem but this time with pops and bangs and the revs were inverse to the throttle. ie, more throttle, less revs... ie... its flooding the engine? After about 5 mins it cleared and I drove back fine.

100% lambda now? its slowly getting worse and worse... is that characteristic of them failing?

 

[Silent_Scone]

Lambda

 

[MicKPM]

100% lambda now? its slowly getting worse and worse... is that characteristic of them failing?

Not really a proven diagnosis of a faulty HO2 i'm afraid - To be sure it needs a diagnostic session as the Live data will show you all you need to know (and more). The heater element only really aids the sensor at initial cold start anyway as the sensors only work correctly when hot (hence the addition of a heater to newer 4-wire units over older 3-wire types). If the heater element was the issue then you wouldn't get the problem once the car reached normal temperature so I personally think you'd be wasting cash by forking out blind on a pre or post-HO2 unit.

At first read I thought it was possibly a failing pedal track at fault as it sounds like a tempremental load related issue. It shouldn't be ruled out just yet either but it could even be an issue with the motorised throttle plate or, as mentioned above, the CPS dropping resolution (These are cheap and easy enough to change yourself so worth a punt before splurging out on a diag). Pure guess work without diagnostics though so report back with whatever "DF" codes have been stored as "memory" or "active" and i'll be able to help more.

Mink

 

[sophiesdad]

Anyone know of somewhere near KT5 that can read codes cheaper than Renault? Cheers[/QUOTE]

i can do it , im in KT2.

 

[blambert]

This forum is awesome. PM'd

 

[blambert]

Met up with sophiesdad (Andy) tonight and he did a full diagnostics for me, computer showed both lambda sensors at fault, with the upstream one around 1500mv constantly, or falling but never within proper limits. Gonna replace the upstream sensor and hopefully that'll fix it all.

Andy, this is the price is was talking about:

http://www.northwestperformance.co.uk/product_info.php?products_id=112