It Wasn't The Maf Sensor

[NeilTindle]

After what seemed to be typical symptoms of a failed MAF sensor I've replaced it and it's no better. I've tried disconnecting the battery to clear the memory and it seems to be better until the ECM starts to make adjustments to the basic settings and makes it worse again. It seems as though one of the sensors, but not the MAF is giving spurious information to the ECM. Which is the next most likely cause? I've also read that it could be a loose vacuum hose but where to look?

[charles]

Could you be more specific about the symptoms?

I'have had several engine running problems with different causes.

[NeilTindle]

I've always thought it was gutless but have posted messages on here and concluded that's how they are and as it's the wife car I wasn't too worried about it. But now it's virtually undriveable. It starts and ticks over ok. First couple of hundred yards are ok then loses power and won't rev. It will eventually get up to 45mph on a light throttle. If I floor it, it just makes it worse. The engine seems to run very hot, not coolant temperature but exhaust temp, to the extent that the manifold glows red. I now suspect the cat converter.

[Masked Marauder]

I've always thought it was gutless but have posted messages on here and concluded that's how they are and as it's the wife car I wasn't too worried about it. But now it's virtually undriveable. It starts and ticks over ok. First couple of hundred yards are ok then loses power and won't rev. It will eventually get up to 45mph on a light throttle. If I floor it, it just makes it worse. The engine seems to run very hot, not coolant temperature but exhaust temp, to the extent that the manifold glows red. I now suspect the cat converter.

Valve timing should be checked as should exhaust for blockages or a collapsed catalytic converter

[NeilTindle]

As far as I'm aware it still on the original cam belt so the valve timing should be as it left the factory. It's done 68k is it due for a new cam belt yet?

Your suggestion on the collapsed cat is what I suspect. I've got another cc which I'll fit this evening and let you know.

[Andrew T]

It has a lifetime Chain, not a belt.

[Topbloke]

if the cat becomes blocked or breaks up and lodges in a bend in the exhaust it will stop the gasses escaping thus causing a braking effect on the engine ( they use this methord on big trucks and coaches) thus driving it on light throttle will give time for the gasses to get around the obstruction and normal driving it will cause the gasses to back up and cause heat build up in the exhaust system , i have seen same symptoms when a car was backed into a earth bank blocking the exhaust and only allowing the car to start and partially rev up before stoping completly (works the same with a pottato however it will fire it out) great spud gun !!!!!!!!!!!!

[Topbloke]

as an afterthought if the system is blocked (because the cat collapsed ) you will need to find out why, ie old age, overfueling, shock ect

[NeilTindle]

Didn't get it off this evening due to the weather but there's definately something loose in there which is probably blocking in the outlet from the cat. Not sure what caused it to fail but it seemed to happen over relatively short time.

[NeilTindle]

It wasn't the MAF sensor but it was the catalytic converter. What a transformation, it's like driving a proper car now. That for the advise. :unsure: