Megane Coupe 1.6 Complete loss of power
Discussion
Hi all. Bought a 1999 Reg Megane Sport Coupe 1.6 the other week and just trying to get rid of the problems it has.
This one is about a lack of power from the engine. Basically, when the engine is warm and I accelerate hard, the car sort of loses power (feels as if i've dropped my foot off the accelerator and the brake is being applied slightly). I've noticed that it only really happens at high-ish revs, for example if I accelerate hard it will lose power at around 3k revs in pretty much every gear.
I first noticed it when on the motorway, I would try to accelerate in fifth and it would just lose power.
It varies with how long it lasts for, sometimes it's just a blip and sometimes i have to take my foot off the accelerator for a good 4 seconds which becomes quite dangerous..
So far I have replaced the ignition coils, fuel filter, cleaned up the TDC sensor and cleaned out the throttle body. I then gave up and took it to the garage where they cleaned the flywheel sensor and replaced the coolant temp sensor, but they couldn't find what the problem was. Took it to a second garage and he checked the fuel lines, did engine diagnostics etc but nothing was coming up.
Completely clueless as to what this is and I don't want to take it to Renault to have my money ripped away from me.
Any help appreciated!
Bordtea
This one is about a lack of power from the engine. Basically, when the engine is warm and I accelerate hard, the car sort of loses power (feels as if i've dropped my foot off the accelerator and the brake is being applied slightly). I've noticed that it only really happens at high-ish revs, for example if I accelerate hard it will lose power at around 3k revs in pretty much every gear.
I first noticed it when on the motorway, I would try to accelerate in fifth and it would just lose power.
It varies with how long it lasts for, sometimes it's just a blip and sometimes i have to take my foot off the accelerator for a good 4 seconds which becomes quite dangerous..
So far I have replaced the ignition coils, fuel filter, cleaned up the TDC sensor and cleaned out the throttle body. I then gave up and took it to the garage where they cleaned the flywheel sensor and replaced the coolant temp sensor, but they couldn't find what the problem was. Took it to a second garage and he checked the fuel lines, did engine diagnostics etc but nothing was coming up.
Completely clueless as to what this is and I don't want to take it to Renault to have my money ripped away from me.
Any help appreciated!
Bordtea
The only things that came up on the lcoal garage's diagnostics were something about the Engine Immobiliser circuit (immobiliser doesnt work basically) and the water coolant temp sensor failure which was replaced. I've sent it off to Renault now as they claim they've got better diagnostic equipment, which I'm a bit sceptical about especially as they're charging me £45 for it...
It does feel like a fuel starvation problem to be honest, but the garage did inspect the fuel lines and couldn't see any problems, though I'm not sure if he checked the injectors.
I've also heard of similar symptoms when the cat fails, any opinions on this?
It does feel like a fuel starvation problem to be honest, but the garage did inspect the fuel lines and couldn't see any problems, though I'm not sure if he checked the injectors.
I've also heard of similar symptoms when the cat fails, any opinions on this?
Bordtea said:
The only things that came up on the lcoal garage's diagnostics were something about the Engine Immobiliser circuit (immobiliser doesnt work basically) and the water coolant temp sensor failure which was replaced. I've sent it off to Renault now as they claim they've got better diagnostic equipment, which I'm a bit sceptical about especially as they're charging me £45 for it...
Either the ecu has stored some fault codes or it hasn't. If one garage has already checked those I fail to see how someone else can find any more. A failing fuel pump isn't going to show up a code anyway. Sounds like a waste of money to me.The trouble is with modern cars, or maybe modern garage mechanics is all they can do is check fault codes and when none show up they go into headless chicken mode. In the days before there were any fault codes to check people actually had to think about what might be wrong. Now they don't even have to understand how engines work.
Pumaracing said:
Either the ecu has stored some fault codes or it hasn't. If one garage has already checked those I fail to see how someone else can find any more. A failing fuel pump isn't going to show up a code anyway. Sounds like a waste of money to me.
The trouble is with modern cars, or maybe modern garage mechanics is all they can do is check fault codes and when none show up they go into headless chicken mode. In the days before there were any fault codes to check people actually had to think about what might be wrong. Now they don't even have to understand how engines work.
X2.The trouble is with modern cars, or maybe modern garage mechanics is all they can do is check fault codes and when none show up they go into headless chicken mode. In the days before there were any fault codes to check people actually had to think about what might be wrong. Now they don't even have to understand how engines work.
I'd like to see the fault code for a birds nest in the airbox, anyway... a friend had that happen after long term storage, and "the car is alright, no codes showing so it can't run badly"...
I especially love it on the VW Audi section of pistonheads: regardless of the problem the first couple response say "use VAGCom to read the codes".
I think some people genuinely believe OBD II will tell you how to fix any issue you have, not long ago someone said their car was booked in to have the codes read because their horn wasn't working!
I think some people genuinely believe OBD II will tell you how to fix any issue you have, not long ago someone said their car was booked in to have the codes read because their horn wasn't working!
Well this seems to be the issue with modern diagnostics, garages just seem to plug the car into their engine management and then if nothing comes up it's a case of "wtf do we do".
Seems like a massive waste of 45 quid if I'm honest and if it comes up with nothing then I plan on trying to get my money back as I did tell them that I'd had 2 diagnositc tests done before and as you say either the ECU stores the fault codes or it doesn't.
May just have to start fiddling about and replacing random bits and bobs. My current suspicions are:
HT Leads
Fuel injectors
Cat converter
Renault are testing it on Monday though so I'll see what they say but I'm not holding my breath tbh.
Seems like a massive waste of 45 quid if I'm honest and if it comes up with nothing then I plan on trying to get my money back as I did tell them that I'd had 2 diagnositc tests done before and as you say either the ECU stores the fault codes or it doesn't.
May just have to start fiddling about and replacing random bits and bobs. My current suspicions are:
HT Leads
Fuel injectors
Cat converter
Renault are testing it on Monday though so I'll see what they say but I'm not holding my breath tbh.
Yeh that's one of the things i'm suspicious of, though I haven't got anything to test so I'll have to just take it to a garage to have it tested if Renault don't come up with anything.
Had a brainwave earlier, could it be a dicky alternator? I've got a slight buzzing noise coming from my battery so initially thought well maybe that could be something to do with it... it can't supply the voltage to get into the high revs when there is load on the engine. Then thought that it's the alternator rather than the battery that supply the voltage once the car's going... if it can't supply the voltage then it won't be able to get above a certain level of revs?
Had a brainwave earlier, could it be a dicky alternator? I've got a slight buzzing noise coming from my battery so initially thought well maybe that could be something to do with it... it can't supply the voltage to get into the high revs when there is load on the engine. Then thought that it's the alternator rather than the battery that supply the voltage once the car's going... if it can't supply the voltage then it won't be able to get above a certain level of revs?
Bordtea said:
Yeh that's one of the things i'm suspicious of, though I haven't got anything to test so I'll have to just take it to a garage to have it tested if Renault don't come up with anything.
Had a brainwave earlier, could it be a dicky alternator? I've got a slight buzzing noise coming from my battery so initially thought well maybe that could be something to do with it... it can't supply the voltage to get into the high revs when there is load on the engine. Then thought that it's the alternator rather than the battery that supply the voltage once the car's going... if it can't supply the voltage then it won't be able to get above a certain level of revs?
Fully charged battery would mask this for a short while.Had a brainwave earlier, could it be a dicky alternator? I've got a slight buzzing noise coming from my battery so initially thought well maybe that could be something to do with it... it can't supply the voltage to get into the high revs when there is load on the engine. Then thought that it's the alternator rather than the battery that supply the voltage once the car's going... if it can't supply the voltage then it won't be able to get above a certain level of revs?
Sounds like it might be to do with the fuel pump, plugs/leads breaking down when hot or even possibly maf/map problem? I'd be looking at the pump first though.
The re checking of fault codes is pretty common these days - not all garages have testers that pick up all the codes.
I'd agree that logical thinking seems to have all but gone in diagnostics thses days - if a computer can't tell them what is wrong, many garages don't have a clue.
The re checking of fault codes is pretty common these days - not all garages have testers that pick up all the codes.
I'd agree that logical thinking seems to have all but gone in diagnostics thses days - if a computer can't tell them what is wrong, many garages don't have a clue.
Magpie, I haven't personally looked at the spark plugs yet but they were replaced around 2 years ago according to history I've got. I also presume that at least one of the two garages would have looked at them aswell, though I will look at them to make sure.
Buff, the second garage told me that he had inspected the complete fuel line and couldn't find any cracks, though I'm not sure if he looked at the pump (though I have heard that generally if the fuel pump goes then it goes completely?)
Vince, what do you mean by the fully charged battery? May just me being stupid... :P
Thanks all
Buff, the second garage told me that he had inspected the complete fuel line and couldn't find any cracks, though I'm not sure if he looked at the pump (though I have heard that generally if the fuel pump goes then it goes completely?)
Vince, what do you mean by the fully charged battery? May just me being stupid... :P
Thanks all
Rollcage said:
Sounds like it might be to do with the fuel pump, plugs/leads breaking down when hot or even possibly maf/map problem? I'd be looking at the pump first though.
The re checking of fault codes is pretty common these days - not all garages have testers that pick up all the codes.
I'd agree that logical thinking seems to have all but gone in diagnostics thses days - if a computer can't tell them what is wrong, many garages don't have a clue.
MAF sensor I'm at a loss at. The first garage did ask me whether I'd cleaned the MAF sensor and I said no as to be honest I don't know where it is on my engine.. 8-) When he opened up the bonnet he made a passing comment along the lines of "this is where the MAF sensor should be) and pointed to the end of the air intake pipe just before the resonator. The air intake pipe I've got obviously isn't stock, it looks like it could be from halfords or something (foil looking).The re checking of fault codes is pretty common these days - not all garages have testers that pick up all the codes.
I'd agree that logical thinking seems to have all but gone in diagnostics thses days - if a computer can't tell them what is wrong, many garages don't have a clue.
You might be able to make out what I mean from this video though it was documenting a different problem (air intake is to the right of the engine):
http://www.youtube.com/watch?v=hM4brpmsgBk&fea...
Again, thanks!
just to check: will it rev past 3k revs, or does it stick there?
Is it the same under load?
I had the above with my BMW. The MAF sensor was to blame: when I put my foot down, the computer would read the open throttle, but the maf would give a different reading, so the fuel would increase but no more revs.
Is it the same under load?
I had the above with my BMW. The MAF sensor was to blame: when I put my foot down, the computer would read the open throttle, but the maf would give a different reading, so the fuel would increase but no more revs.
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