More noise, less power

[Fin]

Well, been down to Mr T, new MAF Sensor £165!!!
I hope that's the cause, guess I'll find out Wednesday when it arrives! If not, their diagnostics are just ovef £50 an hour with vat, which I actually think is quite reasonable.

[Fin]

Thanks Ardent, I've had a read through, and at least now I am sure it's not the VVTi system  s:) s:)
Some good news at last  s:D s:D

[Ardent]

your welcome.
Can not help thinking how usefull a toyota hand held tester would be.
The bay of E

[Fin]

Hand held tester? Haven't seen one of those...
I have an OBDii reader, if that's the same thing??
The write-ups at least explain why I have been having trouble working out whether it was a fuel or timing issue. It appears that the MAF sensor controls both.

[Fin]

Well, I have now replaced everything I can think of (except the radiator, I'll do that this weekend as my new one turned up yesterday).
She still has no power and won't go past about 4.5k except in first  s:( s:(  I've got her booked in with my local Mr T on Tuesday next week, hopefully they'll be able to tell me what it is. I've spent over £1000 on her in the last couple of weeks,money I was hoping to put towards something fun, either getting the head airflowed (has anyone tried that?) or a set of skirts for her  s:( s:(

[Ardent]

keep us updated

[Fin]

Will do. I noticed a couple of threads about temperature senders etc. I'm wondering if it's something along those lines, and it's running on constant 'choke'.... The temp gauge sits nicely in the middle, but does it send a separate signal to the ECU?
That would explain quite a few of my symptoms, including really cr#p mpg figures (down to well below 30 from an average 38 or so). Anyway, I'll have a quick look when I do my rad, but I'm just gonna leave it to Mr T and hope it's nothing serious!!!

[Anonymous]

Did you try and unbolt the main cat to see if it allows it to rev as it might be blocked. Also look for any loose pipe on the air intake mainly after the maf ie around the throttle body.

[Fin]

I originally thought of the cat, I've had 3 'experts' check it over (I even trust 2 of them) they all said the cat was fine.
I've checked all the hoses I can see, and I can't find any leaks/loose ones anywhere. Tbh, I kinda wish it was the cat. I've been offered one at a good price, and I'd probably use it as an excuse for a new exhaust.

[vincenzo]

Maybe you've got a dirty fuel filter giving you trouble?

 l viewtopic.php?f=47&t=46032 l
The thread mentions to depressurize the fuel system first, I don't know the best way to do that???

I read that you spent £400 getting rid of the pre cats, does that mean you got a new exhaust manifold? If so which one?

[Fin]

No, it's the original manifold, but that included 2 o2 sensors and drilling an helicoiling 2 of the 3 amigos.
Just a thought, and possibly showing my ignorance...
I've just done my radiator, chuffed that that went well  s:D s:D , but...
As soon as I turned the key, the water went straight through the system to the rad. Shouldn't it have been held back by the thermostat until it got up to temperature?
Could a knackered thermostat be the cause of my problems???
Just an idle thought, I'm not touching her again, Mr T can sort it out on Tuesday  s;) s;)

[vincenzo]

If the thermostat is stuck open then it will always let water flow straight through, which just means a longer warm up time. Once it's warm everything should run smoothly, but even cold engines will rev to redline if you're nasty.

I thought a fuel filter and pump was one of the most popular culprits for power cutting out at high rpm and as speed increases.
You might as well just ask Toyota to replace the pump & filter and let you know if it needs anything else.

[Fin]

Thanks. The fuel line thing certainly sounds like a possible/probable culprit. I'm working straight through until next Monday  night now, shame as it sounds like a relativelh easy one to check/fix.

[Fin]

Just in case I get bored over the weekend....
How do you clean a fuel filter, it seems an easy job to get at it. I don't know what I would use for cleaning though :/

[AndyWitz]

The fuel filter as you probably already know is located inside the fuel tank. I replaced a friends last week and it was a straightforward job. I'd definitely replace it rather than try to clean it though as it has a very fine mesh and I don't know how you'll be able to tell if your 'cleaning' has been effective or not.
Andy.

[Fin]

Ok, thanks. I've been speaking to Mr T' who is looking at it on Tuesday.
The lower part of the filter is about £12, and the housing is just over £35.At that price, it's not worth messing around trying to clean the old one.
On the grounds that this sounds like a good lead, both are coming in on Wednesday. They come from Belgium, so they take a day longer.
It's still booked for a diagnostic, so fingers crossed on fuel starvation!!!
Seems stange that this all seemed to start when I cleaned my old MAF sensor, maybe a dirty MAF works best with a dirty fuel filter?

[wizzard1983]

Hi there,

Im having exactly the same issues as you on my 2000 mr2 with 99k miles. i have changed the maf + o2 sensors, had a garage look at the exhaust system and my local garage has had a look and cant see anything wrong. please keep us updated...

[Fin]

Hi wizzard, sorry to hear that   s:( s:(  
I know it's frustrating, I've been chasing my tail for a month on this one!!! I should have a firm answer on Tuesday, the good news is that the filter is looking like a solid possibility. It would mess things up the same as the other bits,but it's mechanical so there's no error code   s:roll: :roll: s:roll:  
I'm hoping that's the case, a new one is just over a tenner plus vat from Mr T (I haven't checked the price with Chris from CTP), and there's an excellent write-up on here how to change it  s:) s:)  
Does yours get worse when the engine warms up?

[wizzard1983]

i hadn't even considered the fuel filter... i do hope that's it as that isn't to expensive! yes mine gets worse as it warms up, it drives fine and idles fine up until about 4k then acceleration in 3rd gear is non existent. so much for my local garage... if it hasn't got an engine light on they wont even try to look into fixing it!

[wizzard1983]

Any news? i have taken my after market ecu out and still have the same problem.

[Fin]

Well, I took it up to Mf T.
They had a good look at the air intake, couldn't find any leaks  s:) s:)  
They checked the compression, all looks fine   s:) s:)  
They checked the fuel flow, all good  s:) s:)  
They checked the ignition, all good  s:) s:)  
They checked the exhaust manifold, all good  s:) s:)  
They spent about an hour going through everthing, and charged me exactly nothing at all!!  I had to check I'd heard him properly, I was expecting a bill for about 100 quid   s:crazyeyes: :crazyeyes: s:crazyeyes:  
Anyway... they are convinced that the cat has collapsed. Tbh, that's what I originally thought, but I've had it checked a few times and they all said it was fine. I have been offered one at a good price, just got to convince the other half that she fancies a bit of a drive  s;) s;)
Not sure whether to do the filter tomorrow anyway, and see what happens there. Or get a cat, and do both. Apparently, nobody pressure checks cats any more, but that's what their database says is most likely.

[wizzard1983]

Thanks for the update Fin, i have the car booked into the garage tomorrow for a fuel filter now so will go ahead with that and look for a cat on ebay.

[Fin]

How did you get on with the filter? Has it made any difference?
Be careful if your cat is blocked, the back pressure has been known to torpedo the engine!

[vincenzo]

A restriction anywhere in the exhaust would only reduce the exhaust noise, or so I thought anyway.
More than one exhaust shop has flow tested the cat already right? It would be good to unbolt the cat and test, but that could be a bit of a pain... Less painfull than paying for a new cat that wasn't needed however.

A poor fuel supply will sure cut power, but it won't make the car sound like it has a tuned exhaust as you mention in the op, it would be more like sputtering/coughing/pulsing.
Maybe you should record the sound upload it somewhere so we can hear it.
I wonder if a dirty or sticking/faulty injector could be the cause? Possibly causing a lean or rich condition, affecting sound and power?

I'm surprised at mr t's diagnosis, with no cat flow test or visual inspection, just an expensive guess, although i've noticed heaps of reports of mrT having no clue about MR2's, causing people to blow heaps of cash.

[wizzard1983]

Well the filter made no difference at all, however the mechanic at the garage said he was 99% sure it was a blockage in the exhaust most likely the cat as he took out the o2 sensors and the engine reved fine! I have now ordered a new cat on eBay for £185 and if that doesn't work then I have no clue what it could be.