Weird engine noise coming from my MR2 Mk3..
Discussion
I've recently noticed a strange (and slightly concerning) noise coming from my 2001 Toyota MR2 Mk3's engine and I was wondering if anyone could suggest what it might be based on a rather poor description!
The best way I can describe it is as follows:
Basically, the noise only emanates from the engine when I press the accelerator. Everything sounds great when it's idling/turning over. I first noticed the noise mainly when in 2nd or 3rd gear and at low revs (1,200 - 2,200rpm). However, now it is more obvious even at higher revs and sometimes in 4th gear. The sound itself is obviously mechanical (!) and of a higher pitch than the DOHC generally makes. I'd suggest it's almost tractor-like. I've also noticed a drop in performance. When I press the accelerator the power delivery, especially in 1st and 2nd, seems rather slow and sometimes a bit jumpy. I often find I have to rev more than I'd like (fuel economy is important these days!) in order to pull off smoothly. Even then, sometimes the power delivery and forward motion is poor indeed.
I've check all the fluids. Engine coolant is fine. Oil is fine. I cannot see anything loose or worn on the engine. It has done 73k but passed it's last MOT with flying colours and I've never had any issues with Toyota's before.
Anyway, I think that's as best I can describe the problem. Any help you can provide would be much appreciated. I will, of course, visit a garage should the noise get much worse. I just thought I'd use the power of this forum first! Cheers.
The best way I can describe it is as follows:
Basically, the noise only emanates from the engine when I press the accelerator. Everything sounds great when it's idling/turning over. I first noticed the noise mainly when in 2nd or 3rd gear and at low revs (1,200 - 2,200rpm). However, now it is more obvious even at higher revs and sometimes in 4th gear. The sound itself is obviously mechanical (!) and of a higher pitch than the DOHC generally makes. I'd suggest it's almost tractor-like. I've also noticed a drop in performance. When I press the accelerator the power delivery, especially in 1st and 2nd, seems rather slow and sometimes a bit jumpy. I often find I have to rev more than I'd like (fuel economy is important these days!) in order to pull off smoothly. Even then, sometimes the power delivery and forward motion is poor indeed.
I've check all the fluids. Engine coolant is fine. Oil is fine. I cannot see anything loose or worn on the engine. It has done 73k but passed it's last MOT with flying colours and I've never had any issues with Toyota's before.
Anyway, I think that's as best I can describe the problem. Any help you can provide would be much appreciated. I will, of course, visit a garage should the noise get much worse. I just thought I'd use the power of this forum first! Cheers.
OlberJ said:
I'd put my house on it that the bottom end has gone chocolate on you.
Budget £600-£1000 for a facelift engine swap and gut the pre-cats while it's out.
Based on replacing about 15 of them over 4 years on cust's cars.
Sorry, can you please clarify what "...the bottom end has gone chocolate on you." means?! Budget £600-£1000 for a facelift engine swap and gut the pre-cats while it's out.
Based on replacing about 15 of them over 4 years on cust's cars.
The pre-2004 engines have "issues".
Generally they use a litre of oil every 500 miles or so. A lot of previous owners do not keep up on this and they run dry. They then top them up and sell them on.
Usually, due to this oil use, the lambda sensors get clogged and go very often. This shows up on the dashboard EML.
Again, some types remove the feed to this bulb and sell the car on. Check when you are ignition on and the car not started the EML lights up for a few seconds.
When they let go, the bores go oval and the crank tends to go rather soggy. Shells spin, pistons flap about and lots of heat is created. Some just knock their head in and smoke like a chimney, others go bang properly.
As i say, i've replaced about 15 over the last 4 years due to this and it sounds like yours is in the early stages of going.
Monitor it, keep the oil topped up and see how you get on but i'd be budgeting for a new engine in the near future. While it's out, get the pre-cats in the exhaust manifold gutted. They do nothing but break up and can end up causing issues with bits of ceramic floating around.
Just my tuppence.
Generally they use a litre of oil every 500 miles or so. A lot of previous owners do not keep up on this and they run dry. They then top them up and sell them on.
Usually, due to this oil use, the lambda sensors get clogged and go very often. This shows up on the dashboard EML.
Again, some types remove the feed to this bulb and sell the car on. Check when you are ignition on and the car not started the EML lights up for a few seconds.
When they let go, the bores go oval and the crank tends to go rather soggy. Shells spin, pistons flap about and lots of heat is created. Some just knock their head in and smoke like a chimney, others go bang properly.
As i say, i've replaced about 15 over the last 4 years due to this and it sounds like yours is in the early stages of going.
Monitor it, keep the oil topped up and see how you get on but i'd be budgeting for a new engine in the near future. While it's out, get the pre-cats in the exhaust manifold gutted. They do nothing but break up and can end up causing issues with bits of ceramic floating around.
Just my tuppence.
OlberJ said:
The pre-2004 engines have "issues".
Generally they use a litre of oil every 500 miles or so. A lot of previous owners do not keep up on this and they run dry. They then top them up and sell them on.
Usually, due to this oil use, the lambda sensors get clogged and go very often. This shows up on the dashboard EML.
Again, some types remove the feed to this bulb and sell the car on. Check when you are ignition on and the car not started the EML lights up for a few seconds.
When they let go, the bores go oval and the crank tends to go rather soggy. Shells spin, pistons flap about and lots of heat is created. Some just knock their head in and smoke like a chimney, others go bang properly.
As i say, i've replaced about 15 over the last 4 years due to this and it sounds like yours is in the early stages of going.
Monitor it, keep the oil topped up and see how you get on but i'd be budgeting for a new engine in the near future. While it's out, get the pre-cats in the exhaust manifold gutted. They do nothing but break up and can end up causing issues with bits of ceramic floating around.
Just my tuppence.
Hmm, a worrying conclusion.Generally they use a litre of oil every 500 miles or so. A lot of previous owners do not keep up on this and they run dry. They then top them up and sell them on.
Usually, due to this oil use, the lambda sensors get clogged and go very often. This shows up on the dashboard EML.
Again, some types remove the feed to this bulb and sell the car on. Check when you are ignition on and the car not started the EML lights up for a few seconds.
When they let go, the bores go oval and the crank tends to go rather soggy. Shells spin, pistons flap about and lots of heat is created. Some just knock their head in and smoke like a chimney, others go bang properly.
As i say, i've replaced about 15 over the last 4 years due to this and it sounds like yours is in the early stages of going.
Monitor it, keep the oil topped up and see how you get on but i'd be budgeting for a new engine in the near future. While it's out, get the pre-cats in the exhaust manifold gutted. They do nothing but break up and can end up causing issues with bits of ceramic floating around.
Just my tuppence.
I've just gone to start my car and... the EML did not come on whilst all the others did, albeit briefly. I left the engine to idle and although it generally sounds fine, there is a slight fluctuation in the sound it produces, as if something's very, very subtly misfiring perhaps?
The thing is, I've owned this car for just over a year and it's been absolutely superb. If the problem was what you're suggesting I'm confused as to why it's only rearing its ugly head now. I think I'd best head to my local garage to get it checked...
OlberJ said:
Describe what you mean by sounding like a tractor a little more clearly for me.
Is it a constant metallic whirr or is the car stuttering like it's not getting fuel?
I wouldn't take the tractor description too literally as it's not the best description! The sound is certainly not constant - it only starts when I apply the accelerator. I would say it almost sounds like it's coming from the gearbox area perhaps? It's like something's not quite clashing/meshing correctly but I'm confused by the fact that this isn't continuous. The car doesn't jolt and lurch either. It's just that on occasion I can't pull off as smoothly. I guess there must be an issue with fuel delivery somewhere along the line. Could there be an problem with the coils?Is it a constant metallic whirr or is the car stuttering like it's not getting fuel?
OlberJ said:
Can u video it and upload it to YouTube?
Makes diagnosing these things so much easier.
Cheers mate, but I don't think a video would pick up the noise I'm talking about unfortunately. I'm going to arrange a visit to a local garage tomorrow morning. Fingers crossed the issue won't be what you've outlined above... ! Thanks for your help!Makes diagnosing these things so much easier.
Today I was in my wife's MR2 with her (2001 model) when she noticed the oil light flicker on, a few miles later the engine went bang started shaking the whole car and when we pulled over the coolant was boiling over and steaming out the filler cap.... reading this it would sound like the bottom end has gone. Can anyone advise as to if there was anything that could have been done to prevent this? I topped up the oil for her only a week ago.
I have also seen and swapped a lot of these engines because of wear/damage.
Basically the cylinder bores are oval and the piston ring seal is compromised and uses more oil than it should. When using this oil the catylists and o2 sensors can become clogged (as mentioned) causing mixture / power problems.
I had 2 engines delivered on the toyota van once so I could measure the bores and choose the best one (we had a friendly toyota dealer nearby) and there wasnt a better one ! They were oval from new!
If you love this car my advice would be to convert to the 2zz engine from the 190 Celica. It wakes these cars up and is a very nice power/weight car after this conversion. Rogue motorsport are the only ones I know that do this properly (ie toyota ecu and wiring etc).
HTH
Tony
Basically the cylinder bores are oval and the piston ring seal is compromised and uses more oil than it should. When using this oil the catylists and o2 sensors can become clogged (as mentioned) causing mixture / power problems.
I had 2 engines delivered on the toyota van once so I could measure the bores and choose the best one (we had a friendly toyota dealer nearby) and there wasnt a better one ! They were oval from new!
If you love this car my advice would be to convert to the 2zz engine from the 190 Celica. It wakes these cars up and is a very nice power/weight car after this conversion. Rogue motorsport are the only ones I know that do this properly (ie toyota ecu and wiring etc).
HTH
Tony
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