Help a newbie?

[andibell]

Hello everyone.

So I finally got round to buying myself an MR2 in January, sort of by accident...  Long story short:  Went looking for a practical small hatch type run-around to get me to work and back and sat next to an A3 at a dealers was a little black 2001 plate '2 with matched black&red leather interior.  It spoke to me, I spoke to the garage and ended up taking it home.

All was great until a few weeks ago when it developed a rather curious, diesel-esque rattle.  I tried recording it, but it turns out it's harder than you'd think to drive and record your engine, even when it's behind your head, so I'll try and describe it instead.  1st off, it's not there at idle, when stationary, when the clutch is dipped, etc or anything below 2500k revs.  Between 2500-4000 revs, in any gear and irrespective of speed, there's a constant, rattle/tapping noise.  Now I know almost nothing about engines, so I spoke to a really helpful guy on here (Muffdan) who happened to live right round the corner and kindly agreed to take a listen and offer some advice.  Ended up with the car going in to Silverstone Performance last weekend firstly to get the pre-cats removed, (possibly a little too late, but more on that later), and also the timing-chain-tensioner thingy replaced as there was thinking that that could be the cause of the noise...  
It wasn't.
So, now I still have the rattle and it turns out the engine also appears to be suffering from the oval bore problem as it's using quite a lot of oil.  When the pre-cats came out, there was a tiny amount of white powdery dust in the manifold, at the top, so I assume it's possible (probable) that some of this has been sucked in to the engine.

So I guess my questions to you knowledgeable chaps are:

1/ Any ideas what could be causing the noise?  Does it sound familiar to anyone?
and
2/ As it looks like I'm going to end up swapping out or having the current engine rebuilt, what advice can anyone who's done this offer on parts, labour, costs, etc, etc, etc.

I've pretty much resigned myself to the fact that it will need a new engine and will cost £££'s, but I love the car and don't want to part with it, so I'm prepared to put in the effort to get it running properly again.  I've seen a re-con/re-furb 1ZZ engine going for £950 with a 6 month warranty or £1050 with a 12 month warranty.  I've also seen people on e-bay offering to supply and fit a replacement (assumably salvaged) engine for that price as well as found someone who said they can rebuild my existing engine for £1k, although not too sure about that last option, can't see it being the best solution.  I've also seen (read) talk of putting in the 2ZZ or a V6 conversion, can anyone that's done either fill me in on what's involved, how much it cost and what sort of effect it had on insurance?

Thanks all in advance.

[mrzwei]

Stand by for quite a few replies to this   s:D s:D  . If it's using a lot of oil then the oil control rings are letting it past so it's probably oval bore. At the very least you are looking a a replacement half engine but then somebody has to take off and replace all of the bits that need to be kept. Given that SP couldn't pin point the problem then a safer bet would be a reconditioned engine (or one of known milage and quality). The main cat should also be replaced. A £1000 recon of yours is a way forward but you need to be confident about exactly what they are going to do.

Different engine options are many and others are more qualified to comment on this than me.

[frogger]

There's many many articles on here about your options, but heres a recent one...  l viewtopic.php?f=11&t=30247&view=unread#unread l

My personal method would be:

a) Contact Woodsport or OlberJ to check on the price of a v6 or 3S-GTE 2ltr turbo swap, and ring sky insurance, a plan, and adrian flux to get an idea of insurance.

b) If option a) proves to be too expensive - go with a recon engine with warranty (and good seller feedback if from ebay), or a low milage post-03 engine from a salvage yard. If you can get the supplier of the engine to fit for a bit extra on top then go for it, then go back for an oil + filter change ~150 miles later if fitting a recon.

Good Luck!

[andibell]

....Given that SP couldn't pin point the problem....

To be fair to them, they only had the car for a very limited time and mostly to remove the pre-cat.  After we'd discovered the oval-bore issue (or at least evidence that it's probably) it didn't really seem to be worth while looking for the cause of the rattle.  That said, Matt did say that he suspects it's VVTi related as it's only happening under load in a certain rev-band.  I'm asuming that swapping out the whole engine will alleviate the problem...    s:?: :?: s:?:

[frogger]

I'm asuming that swapping out the whole engine will alleviate the problem...    s:?: :?: s:?:

So long as the new engine is good   s:lol: :lol: s:lol:  

There's nothing left behind to carry on making a rev related noise if you swap the whole engine (unless it was gearbox related, but I would have hoped silverstone performance would have instantly diagnoised it as coming from the gearbox not the engine if this was the case).

[muffdan]

Hi Andy, good to see you post up!

Its definitely not the gearbox. The rattle sounds exactly like a knackered big end does, but it only happens at a specific rpm (in any gear) and I head it happen both on and off load although not consistently. It's not any of the  heat shields either; all of them are nice and tight.

You're right in that it doesn't matter what the noise is now though if you're swapping the engine.

[andibell]

Another quick question...  I've had a look around and everyone seems to get different MPG, which you'd expect down to varying driving styles, journey types etc...  But has anyone else noticed a significant drop in MPG following pre-cat removal.  My useage is pretty stable, the car really only gets used to get me to work and back, it's the same journey every time - 60/40 split motorways/a-roads.  I don't drive that slowly, I'll admit, but I do let the engine warm up and try not to accelerate / brake too hard.  I've monitored my fuel useage and it's been pretty constant at around 330 - 360 miles to a tank, so 40mpg ish ever since I got the car.  Since the pre-cats came out, I've had to fill the tank twice and only got 260 out of the first tank and 280 out of the 2nd.  Also, the needle dropped like a stone in the last quarter tank...

[cclarke99]

My car ('02, 65K) also sufers from a rattle at specific engine speeds and particularly under load. From the sound of it, I don't think it's the engine, and I've tried all the heatshields. I've concluded that it's more like something loose in the silencer.

[andibell]

That's thought worth exploring.  

Mine seems very much throttle related, I can be doing any speed and over 2500 rpm and it's there, but dip the clutch and it goes away...

[skinz]

My car ('02, 65K) also sufers from a rattle at specific engine speeds and particularly under load. From the sound of it, I don't think it's the engine, and I've tried all the heatshields. I've concluded that it's more like something loose in the silencer.

Ive got the same goin on atm(02, 41K), when I rev up theres a sort of rattle/vibration, like 2 plates hitting together, happens on rev up and then rev down, seeminly not from heatshields as these have been checked out, but ive still got precat (i think... previous owner wasn't too sure what they were :s), but no symptoms such as oil loss or lack of power, but still getting them gutted on the 17th, so when I go to exhaust place will see if the guy can locate this rattle/vibration - just a pain in the ass as i can hear it more with top down and the suns been out - so just cranking up the basslink lol

[andibell]

so just cranking up the basslink lol

If only the OEM stereo and speakers in mine were decent enough to drown out the noise!   s:lol: :lol: s:lol:  It's next on the list of things to replace.

[normanh]

MPG will depend hugely on your driving style, I am like "Driving Miss Daisy" and always get 400 miles per tank.


normanh

[Anonymous]

I am like "Driving Miss Daisy's 200 year-old Grandmother"

Fixed that for you  s;) s;)

[andibell]

I drive like Miss Daisy would have been driven if her driver were a middle aged German man with a brother call Ralph....   s:scared: :scared: s:scared:

[roger]

Andy, I assume the battery was unplugged for a while after the Pre-cats taken out, which then ensures the ECU relearns the new format.

Also I appreciate your mpg calculation is only approximate, but working out per tankful is VERY approximate!

If you want to be nerdy like me, and a few others, go to fuelly.com - link in my signature.

[andibell]

Thanks...  I haven't removed the battery, didn't know I needed to.  Is it just a matter of unplugging it, leave it off for a while and put it back on or will I need to reset anything afterwards?  I assume I can just un-do one of the terminals?

I worked out the MPG based on litres in vs miles travelled (I always put in 40 litres and reset the tripometer) and it's been fairly constant for the short time I've had it (about 4 months now).  Obvious dips if I'd done more local driving than usual and a couple of times I got 400 miles from 40 litres on pure motorway runs, so a drop of about 60-80 miles from the same volume of fuel is a bit worrying.  I tend to alternate between Shell Optimax and BP Ultimate, depending on whether I fill up on my way to or from work, haven't noticed much difference between the two...

[frogger]

Yep, just unplug it for a while. No need to do anything else.

Even simpler - you can just pull the appropriate fuse in the engine bay. I forget which it is, there's a choice of two in the engine bay fues box which might do the job - Pull 'em both and you cant go far wrong lol. Though someone may be along to clarify soon  s:lol: :lol: s:lol:

[cclarke99]

EFI 1 is the fuse for the ECU supply thats on all the time

[andibell]

Thanks cclarke - I'll go locate and pull it now whilst it's not going anywhere for a few hours.    s:) s:)

[andibell]

Looks like the mileage is back to normal...  I hope.  Got 350 miles from the last 40 litres, which was split pretty much 50/50 between motorway and local roads, so a combined cycle of about 40mpg.  No complaints there.   s:D s:D  

Now if only I can figure out what's causing this damned rattle......   s:twisted: :twisted: s:twisted:

[SimonC_Here]

I'm just wondering how you got 40ltrs in the MR2. My normal fill up has been around 37ltrs.

I did manage to get 39.1 in once but that was driving around with the light on and clenched buttocks!  s:oops: :oops: s:oops:

[andibell]

I'm just wondering how you got 40ltrs in the MR2. My normal fill up has been around 37ltrs.

I did manage to get 39.1 in once but that was driving around with the light on and clenched buttocks!  s:oops: :oops: s:oops:

Luck?!    s:D s:D    

I always use high octane fuel, BP Ultimate or Shell Optimax, always let the engine warm up before I set off, rarely accelerate hard, don't tend to go over 75-80mph and check the tyre pressures weekly.  I've heard other people report anything between low 20's through to 40mpg, so I guess it's pretty variable.  A lot of my driving is A-roads and motorways, which probably helps get the average mpg up.

I'm sure it will drop off rapidly once I start with the tinkering!    s:lol: :lol: s:lol:

[Mad Matt]

I don't think the ability to get 40l in has much to do with economy, or have I missed something? Economy would have more to do with how far you went on that 40l  :-) :-) :-)

[andibell]

I don't think the ability to get 40l in has much to do with economy, or have I missed something? Economy would have more to do with how far you went on that 40l  :-) :-) :-)

Must learn to read....    s:lol: :lol: s:lol:

[SimonC_Here]

Yes, it was how do you fit in 40 litres not your MPG.

My best MPG with the turbo in has been 38.6mpg!

Simon