Loss of power when accelerating

[RubixRonnie]

Hi everyone,

So I thought it was the clutch but I've changed my mind.
When cruising around town, below 60 it's fine.
But, if I try and accelerate hard or get it up the revs it just isn't pulling like it should. It isn't revving out, it's not revving enough and the acceleration isn't there.
Any ideas?

Cheers in advance
Danny

[Carolyn]

Hi everyone,

So I thought it was the clutch but I've changed my mind.
When cruising around town, below 60 it's fine.
But, if I try and accelerate hard or get it up the revs it just isn't pulling like it should. It isn't revving out, it's not revving enough and the acceleration isn't there.
Any ideas?

Cheers in advance
Danny

Has it got a fresh air filter?

[RubixRonnie]

It needs a new one but even with it out there's still a loss of power

[Carolyn]

The next usual suspect for this symptom is a poor earth on the crank shaft sensor.  It's on the bottom of the timing cover towards the bulkhead.

[RubixRonnie]

Thanks I'll have a look.
There is some oil on the MAF sensor cable,  it I've had the MAF off and it looks clean.
Also, I can't remember if these engines run hot and the temp in the car was ok but there was some real heat coming off the engine after a 30minute drive.

[Carolyn]

Thanks I'll have a look.
There is some oil on the MAF sensor cable,  it I've had the MAF off and it looks clean.
Also, I can't remember if these engines run hot and the temp in the car was ok but there was some real heat coming off the engine after a 30minute drive.

'looks clean' and 'is clean' can be two different things with MAFs.  Take the O ring off (so you don't melt it) and spray thoroughly with carb cleaner.

These engine bays can get surprisingly hot.

[RubixRonnie]

Will do thanks so much! I'll give those a go and see what happens!

[RubixRonnie]

Just had the reader on it and these were the codes You cannot view this attachment.

[Ardent]

Possible poor connection somewhere
When get it out. Have a look up inside one of the channels should see 2 fine wires.
Are they intact?

Anyone in your area that could temp swap a maf over?

[RubixRonnie]

Cleaned the MAF and much improved but still not like what I know it can do.
Will check connection, I think it needs a service to be honest, the bloke before said he'd had it done and it's stamped but I'm not so sure.
Also. Air filter is filthy! Ordered a new one.
At least it ain't the clutch!

[jonbill]

the IAT and the MAF are in the same unit. the errors are open circuit. they're probably from when you started the car with the MAF disconnected.

[RubixRonnie]

Possible poor connection somewhere
When get it out. Have a look up inside one of the channels should see 2 fine wires.
Are they intact?

Anyone in your area that could temp swap a maf over?

Thanks, but not sure which channels you mean?

[Ardent]

If we call the bulb end the bottom and the  elec connector end the top.
Turn upside down and look down either side of the main body sort of internally.

Dead easy to show. Not to explain.

[Petrus]

These engine bays can get surprisingly hot.

It is more that they can appéar to be surprisingly hot because at the end where one is standing with the lid open the muffler is stacked on top of the cat. The heat equivalent of stain on stain and the heat wave from that hits your face.
If anything the engine room is relatively cool but for that cramped exhaust lay out.

[Fin]

I had a problem with mine when I first got it:
Everything was fine under low power, cruising etc, but when I pressed the accelerator hard, I got a bit more noise, but a drop in power.
I looked all over the engine for problems, checked everything, replaced the MAF and filters etc.
In the end, it all came down to a blocked CAT (it was suggested to check it on here, but a couple of "specialists" told me it was fine, because some of the gas was getting through, just not enough).
Just another avenue to check...

[shnazzle]

These engine bays can get surprisingly hot.

It is more that they can appéar to be surprisingly hot because at the end where one is standing with the lid open the muffler is stacked on top of the cat. The heat equivalent of stain on stain and the heat wave from that hits your face.
If anything the engine room is relatively cool but for that cramped exhaust lay out.

Still flippin hot in there! Regardless of whether it's cool for where it is. Those crossbars can't be comfortably grabbed when you've had a good run.

It's hot in there.

[RubixRonnie]

I had a problem with mine when I first got it:
Everything was fine under low power, cruising etc, but when I pressed the accelerator hard, I got a bit more noise, but a drop in power.
I looked all over the engine for problems, checked everything, replaced the MAF and filters etc.
In the end, it all came down to a blocked CAT (it was suggested to check it on here, but a couple of "specialists" told me it was fine, because some of the gas was getting through, just not enough).
Just another avenue to check...

Thanks Fin, how would one go about checking if I my CAT was blocked?

[Petrus]

Still flippin hot in there! Regardless of whether it's cool for where it is. Those crossbars can't be comfortably grabbed when you've had a good run.

It's hot in there.

The point is avoiding confusion about it being hotter than front engined configurations.

The MR2 configuration operates coolere than traditional front engine and is only compromised at the rear which is what you feel when the hot air rising from the too compact exhaust hits you upon opening the lid.

With a more freely flowing exhaust, not wrapped but with OEM shields!, even the black heat shield in the back does not get scolding hot on a spirited country drive here.

That observed, all ´modern´ (post eighties) engine installations get hot because of the sound containment wrapping by panels.
Our MR2 is at an advantage because the engine compartment is not pre-heated by hot air from the radiator ánd is vented immediately to the outside world at the rear.

[Joesson]

I had a problem with mine when I first got it:
Everything was fine under low power, cruising etc, but when I pressed the accelerator hard, I got a bit more noise, but a drop in power.
I looked all over the engine for problems, checked everything, replaced the MAF and filters etc.
In the end, it all came down to a blocked CAT (it was suggested to check it on here, but a couple of "specialists" told me it was fine, because some of the gas was getting through, just not enough).
Just another avenue to check...

Thanks Fin, how would one go about checking if I my CAT was blocked?

That was my first thought when you posted about lack of power when accelerating. From what I've read on here, not so much in recent times, is that is symptomatic of a blocked CAT. I didn't like to mention it as the typical  reason for a blocked CAT is breakdown of the precat's.
The simplest way to check if that is the problem would be to check their condition by removing the top two O2 sensors.

[RubixRonnie]

Thanks Joesson,

I'm calling a garage I know in Spennymoor tomorrow who will remove precats.
So I'll get them to check it.
Hope it isn't pre cats .

I'm fairly sure it isn't given after I cleaned the MAF sensor it was nearly up to full performance!

[RubixRonnie]

Booked in on 1st July to check pre-cats, fingers crossed! In the meantime I'll put the new air filter in when it arrives.
Taking it for a spin later so will see how I get on.

[Topdownman]

Once you have had that work done, you could try some redex in the fuel to clean the lines.

Then follow that up with some cataclean to clean the cat.

May not do anything but at least you know its been done.

I like to do a bottle of cataclean a few weeks before the MOT.

[RubixRonnie]

Thanks Topdownman, I'll make sure to do that if the engine isn't already toast and those pre-cats are in tact!

[RubixRonnie]

Took it out for a little run today, and the MAF cleaning hasn't changed anything, which is weird because as soon as I'd done it and took it out, the performance seemed much better. Such a shame, fearing precat issue. Not doing anything else now until it's been into S Cars for precat check/removal/cat clean!

[Ardent]

not a happy read and feel your frustration/anguish.

The pre cats themselves do not fail. Something further up the food chain has caused them to fail. If that's the case. That doesn't make great reading either.