Car not revving right

nd

Hi, so a relatives car isn't revving properly. It was revving ok in neutral but was not revving well in gear and was struggling to maintain 50 kph.

Now it's struggling to get over 2k revs even in neutral.

I took a quick video of how it sounds. This was open throttle.

It had a mixture too lean engine light. And had a long term fuel trim of about +25. I tried disconnecting the front o2 sensor just in case that was faulty but the engine performance is still the same.

Any thoughts?

Thanks.

nd

Anyone know where or if a 02 almera has a fuel filter? I've read online that it hasn't one but micksgarage sell them.

Can anyone tell me what the thing circled in red is?



Thanks.

joujoujou

Don't know what is in a red circle, but I'm almost sure fuel filter is in the fuel tank.

Greyfoot

thats an aftermarket fuel pressure regulator, feeding to injectors. Trace the filter the other way, along the goldish line.

JohnBoy26

The fuel filter is in the tank and is accessible from under the back seat. Im not entirely convinced its your issue though.

CianRyan

Fuel filter I think it on the bulkhead, near the passenger wing. Could be getting mistaken though.

That sounds like the ECU is causing a fuel cut, there could be a fueling issue that it's detected and it wont let you over rev and destroy the engine?
That could be all bollocks but well, that's the first thing that popped to mind.

JohnBoy26

CianRyan wrote: »

Fuel filter I think it on the bulkhead, near the passenger wing. Could be getting mistaken though.

That sounds like the ECU is causing a fuel cut, there could be a fueling issue that it's detected and it wont let you over rev and destroy the engine?
That could be all bollocks but well, that's the first thing that popped to mind.

That's was the older model

CianRyan

JohnBoy26 wrote: »

That's was the older model

Read the year wrong, was wonder why the engine looked odd to me.

nd

JohnBoy26 wrote: »

The fuel filter is in the tank and is accessible from under the back seat. Im not entirely convinced its your issue though.

thanks

Is it part of the fuel pump? I looked under the rear seat yesterday and saw the fuel pump there. There is plenty of petrol being pumped by the fuel pump, so would that rule out a clogged fuel filter?

Any guesses as to what might be the issue?

I suppose it could be 101 things.

Waterson

Try disconnecting the air flow meter and see if this improves driveability. A LTFT reading of +25 is obviously way too high. The ECU is increasing duty cycle of injectors to compensate for bad readings I would suggest from faulty lambda sensor or MAF (without live data hard to say for sure). Check the waveform of the lambda sensor should be fluctuating between roughly 0.2 to 0.9 V when driving at a steady speed. MAF readings should increase from about 1.5 V @ idle to around 4-4.5V at wide open throttle and should have a linear waveform when plotted against engine speed.

CJhaughey

Sounds like the worn timing chain issue that Almera's have.
Check the tensioner and see how far it is extended, is its more than 12mm its at the limit of adjustment.

nd

Waterson wrote: »

Try disconnecting the air flow meter and see if this improves driveability. A LTFT reading of +25 is obviously way too high. The ECU is increasing duty cycle of injectors to compensate for bad readings I would suggest from faulty lambda sensor or MAF (without live data hard to say for sure). Check the waveform of the lambda sensor should be fluctuating between roughly 0.2 to 0.9 V when driving at a steady speed. MAF readings should increase from about 1.5 V @ idle to around 4-4.5V at wide open throttle and should have a linear waveform when plotted against engine speed.

Thanks. i tried disconnecting the Maf sensor and it didn't seem to make a noticeable difference, other than stalling when I initially disconnected it.

The front lambda sensor is pretty much on 0.1 volt constantly. When I disconnect it it defaults to about .4 volts. But doesn't make a noticeable difference to how the engine is.

The maf reading goes from about 4g/s at idle to about a max of 21g/s.

nd

CJhaughey wrote: »

Sounds like the worn timing chain issue that Almera's have.
Check the tensioner and see how far it is extended, is its more than 12mm its at the limit of adjustment.

Thanks. I'll have to have a look online to try to see how to check that

nd

CJhaughey wrote: »

Sounds like the worn timing chain issue that Almera's have.
Check the tensioner and see how far it is extended, is its more than 12mm its at the limit of adjustment.

Well seems like this is the issue so thanks again. Just needed to remove the rocker cover to see it.

The tensioner looks to be out to about 20mm or so.



Has anyone ever replaced a chain on this model almera? Is it a possible diy job?

If not anyone have any idea of the labor cost from a mechanic?

Thanks.

CJhaughey

nd wrote: »

Well seems like this is the issue so thanks again. Just needed to remove the rocker cover to see it.

The tensioner looks to be out to about 20mm or so.



Has anyone ever replaced a chain on this model almera? Is it a possible diy job?

If not anyone have any idea of the labor cost from a mechanic?

Thanks.

DIY, yes if you are very competent and have access to air tools.
I would say a good indy would be a better bet. Maybe ~400ish or so?