C70 t5 2.3t engine issues

[Aj_roy]

Hey guys i am really hoping you can help me. I am having a nightmare. I recently bought a c70 t5 2.3t 1998 and have been loving it. I was going to write a really long explination of the issue and how it occured and the fustrations i had but it it reached more than 1 page on a word document and it would bore people. So long story short my car has developed a misfire. I tried replacing the coil packs and spark plugs, which the old spark plugs were horrendous.the guy at the garage i went to said he was surprised that it was running at all. We replaced everything and still the misfire was still there. We did a compression test and found that cylinders 4 and 5 where very low. He said that he thinks that the valves have worn excessively and more than linkey burt out. To say i was devistated was an understatment at this point as i had spent almost a grand on top of the buying price of the car to that point and had got a new exhaust 3 days earlier which had cost me £500.

I am in need of a cylinder head reconditioning which i can get done for £200. But i am massively struggling to find someone in sheffield that will be willing to take on the labour for a decent price. I am in a masive dilemma as i really dont want my volvo experience to end here and i would love to have this back on the road but spending almost twice of the value of the car on the car just seems to bother me a little. I am hoping you lovely folks can point me in the righr direction of who to go to, to get a quote for this job and if you can give me any recommendations for what to do. Any help would be highly appreciated.

Thanks peeps

Arjun

[deathrider311271]

if the car is drivable, contact Tim Williams as he is more than capable of doing this job

[Kingsford G]

Test the compression again and then put some engine oil in the low compression cylinders and test again,if the compression goes up its your rings gone so the head job will be a waste of money if it stays the same then happy days,just a head job.

[Doingitsideways]

Or could just be the head gasket across two cylinders?

Quite rare for the valves to burn out on these to be fair.

[Biff]

Kg is talking sense. I've not heard of the valves burning out, I reckon it could be the gasket also as it doesn't have to mix oil & water or smoke excessively.
If it does turn out to be your head why not stick a second hand one on if your at a budget? I'm sure one of us will have one knocking about.
With your car being a 98 you need to say whether it has a throttle cable or not as this relates to what engine it has.
Good choice of car, hopefully these problems wont put you off.

[960kg]

Burnt Valves are common on these engines (https://www.google.co.uk/search?hl=en&site=imghp&tbm=isch&source=hp&biw=1776&bih=875&q=Burnt+Valves+t5&oq=Burnt+Valves+t5&gs_l=img.3...8555.14238.0.16332.15.8.0.7.7.0.244.7 52.7j0j1.8.0....0...1ac.1.64.img..4.11.752.N-wZZdFU-m0)because a few owners only use 95ron and the carbon will build up around the valve and even parts break off them.

[Aj_roy]

Hi guys thanks for your replies. Its an me7 engine. What had happened was that i had a new straight through exhaust put on last friday and until monday it was fine. Then t started misfiring. I took it to a garage who told me that it was not a misfire as it was too smooth and that it would be down to the lamds sensor not being able to measure the airflow out which made the engine compensate by adding in more fuel, this is why it was running so rough. I had a remap booked a couple of days after anyway, which they would be able to program in to the ecu to bypass the sensors so i wasnt too worried.

So i made the trip from sheffield to burton. A 50 mile trip. Chris at Cc tuning knew straight away that it was a misifire and like me was hoping at that point it just needed a new set of plugs. We replaced the plugs and coil packs with no luck. The old plugs hd obviously not been changed for atleast 40-50k as they were hugely erroded. Thats when we did the compression test and found that cylinders 4 and 5 were running very low. Because it had been run with very bad plugs and possibly the coil pack was damaged as well as no water or engine oil loss, he thought it would be the valves that had been damaged.

Sorry for such a long explination. I am hoping that this will make more sense. I have contacted Tim so hopefully he can help me. i think either way in my case the cyclindee head will need taking off. So hopefully i can find someone who is willing to do this and then go from there. Thanks for all your input and help guys

[Doingitsideways]

Standard T5s can run on 95 quite happily.

Christ, that's like rocket fuel compared to the crap Americans run them on!

Remapped though, gotta be 98. I wouldn't even use BP's crappy 97.

[mike 850]

Hi guys thanks for your replies. Its an me7 engine. What had happened was that i had a new straight through exhaust put on last friday and until monday it was fine. Then t started misfiring. I took it to a garage who told me that it was not a misfire as it was too smooth and that it would be down to the lamds sensor not being able to measure the airflow out which made the engine compensate by adding in more fuel, this is why it was running so rough. I had a remap booked a couple of days after anyway, which they would be able to program in to the ecu to bypass the sensors so i wasnt too worried.

So i made the trip from sheffield to burton. A 50 mile trip. Chris at Cc tuning knew straight away that it was a misifire and like me was hoping at that point it just needed a new set of plugs. We replaced the plugs and coil packs with no luck. The old plugs hd obviously not been changed for atleast 40-50k as they were hugely erroded. Thats when we did the compression test and found that cylinders 4 and 5 were running very low. Because it had been run with very bad plugs and possibly the coil pack was damaged as well as no water or engine oil loss, he thought it would be the valves that had been damaged.

Sorry for such a long explination. I am hoping that this will make more sense. I have contacted Tim so hopefully he can help me. i think either way in my case the cyclindee head will need taking off. So hopefully i can find someone who is willing to do this and then go from there. Thanks for all your input and help guys


2 cylinders next to each other normally means head gasket

[Aj_roy]

Does anyone have any idea how I would double check exactly what the issue would be? I have had a quote from a company in London that have said they can do a full engine rebuild for £1800 fully fitted with new cambelt etc. Do you guys think its worth it? I am wondering also if anyone on here would be interested in buying it as a project if they have the skills to do it themselves? considering possibly cutting my losses with it now. proper gutted about this especially as I have spent £500 on an exhaust 3 days before it happened :(

thanks for all your help guys

[Doingitsideways]

Not really without pulling the head off, Fella.

The oil down the bores would rule out the rings, but the HG or a burnt valve would still be the same.

My money is firmly on the HG though, especially as the two cylinders with no compression are next to each other.
Chances of two valves burning out on different cylinders at the same time are extremely slim.

[Mart5in]

I +1 on it being the head gasket.

As above, it's between 2 cylinders. and it's not using oil or water.

£1800 for a "rebuilt" engine isn't that great imho.

Whatever happens, the cylinder head has to come off. I doubt it's burnt/broken/damaged valves - that's not common at all.


Also, if 4 and 5 were lower, how much lower?

[Aj_roy]

Not really without pulling the head off, Fella.

The oil down the bores would rule out the rings, but the HG or a burnt valve would still be the same.

My money is firmly on the HG though, especially as the two cylinders with no compression are next to each other.
Chances of two valves burning out on different cylinders at the same time are extremely slim.

Thanks mate. i am hopefully going to find someone that will be willing to take off the head for me etc, have a look and go from there with it. can you recommend anyone at all? i think my breakdown cover allows me to get the car towed anywhere in the uk.

[Aj_roy]

I +1 on it being the head gasket.

As above, it's between 2 cylinders. and it's not using oil or water.

£1800 for a "rebuilt" engine isn't that great imho.

Whatever happens, the cylinder head has to come off. I doubt it's burnt/broken/damaged valves - that's not common at all.


Also, if 4 and 5 were lower, how much lower?

thanks for your reply. if i can remember correctly cylinders 1 to 3 where around 180. cylinder 4 was about 150 ish and cylinder 5 was about 130 which was the lowest.

when the issue happened i was in Sheffield and when i took it to a garage they told me it was too smooth to be a misfire. because i was told the engine light would come due to the decat i ignored that when it came it. the garage told me it was due to the decat but because i had a remap booked in 2 days later that didn't bother me. so i drove it from Sheffield to burton. i think i may have made the issue worse by doing this. Chris at cc tuning was pretty confident that the issue was down to the valves as the spark plugs where so bad so i don't know what to go on now.

[Kingsford G]

Go to halfords and get a compression tester,oil in the bores and measure before and after,if its a head job it might be in your budget to get it sorted and you can drive it a long time.My mates Gull is near 300k and still going strong.These engines can easily beat most diesels on a life span if looked after.Your problem is most likely to be due to the bad plugs and 4 and 5 must`ve been a bit different from the rest.

[deathrider311271]

My V70 2.5T had burnt out valves on cylinders 4 and 5 due to faulty knock sensors

[Aj_roy]

Go to halfords and get a compression tester,oil in the bores and measure before and after,if its a head job it might be in your budget to get it sorted and you can drive it a long time.My mates Gull is near 300k and still going strong.These engines can easily beat most diesels on a life span if looked after.Your problem is most likely to be due to the bad plugs and 4 and 5 must`ve been a bit different from the rest.

Cheers for that mate, I think a lot of people are very surprised that it may be the valves that have been burnt out. Today I have spoke to Shem from Shemtek automotive solutions who says he is more than happy to do the job if it needs doing at all including a reconditioned head for around £500-600 which I am pretty happy with.

I am so glad I am getting somewhere with this now. I would hate to break my Volvo up or sell it as spares and repairs with the amount of time and money I have spent on it. if all goes well I should have it up and running by the end of Nov. fingers crossed ey!

Really appreciate you all taking your time out to help me guys!

[960kg]

Standard T5s can run on 95 quite happily.

Christ, that's like rocket fuel compared to the crap Americans run them on!

Remapped though, gotta be 98. I wouldn't even use BP's crappy 97.

Standard T5`s are still turbo ...Lol, and should be 98ron as per handbook.

95ron is for use just now and again and not continual use..........otherwise you get a big bill after so many thousands of miles.

[Kingsford G]

Cheers for that mate, I think a lot of people are very surprised that it may be the valves that have been burnt out. Today I have spoke to Shem from Shemtek automotive solutions who says he is more than happy to do the job if it needs doing at all including a reconditioned head for around £500-600 which I am pretty happy with.

I am so glad I am getting somewhere with this now. I would hate to break my Volvo up or sell it as spares and repairs with the amount of time and money I have spent on it. if all goes well I should have it up and running by the end of Nov. fingers crossed ey!

Really appreciate you all taking your time out to help me guys!

Shem is a good lad and knows what he is doing so let him do the magic.

[Jamest5r]

Cheers for that mate, I think a lot of people are very surprised that it may be the valves that have been burnt out. Today I have spoke to Shem from Shemtek automotive solutions who says he is more than happy to do the job if it needs doing at all including a reconditioned head for around £500-600 which I am pretty happy with.

I am so glad I am getting somewhere with this now. I would hate to break my Volvo up or sell it as spares and repairs with the amount of time and money I have spent on it. if all goes well I should have it up and running by the end of Nov. fingers crossed ey!

Really appreciate you all taking your time out to help me guys!

Shem is a good shout mate he did a recon head on my V70 and had it back in a week no problem at all.

[Mart5in]

Standard T5`s are still turbo ...Lol, and should be 98ron as per handbook.

95ron is for use just now and again and not continual use..........otherwise you get a big bill after so many thousands of miles.

I can't find anything in my handbook that says I should use 98 over 95. (or maybe I just skipped that page to look at more important things lol)

Anyways, 95 doesn't cause burnt valves any more than 98 would. burnt valves are down to running lean, incorrect ignition timing or using poor quality fuel - which can result in carbon buildup. fuels which lack lubrication can also burn your valves - that's not really an issue here though.

[960kg]

I can't find anything in my handbook that says I should use 98 over 95. (or maybe I just skipped that page to look at more important things lol)

Anyways, 95 doesn't cause burnt valves any more than 98 would. burnt valves are down to running lean, incorrect ignition timing or using poor quality fuel - which can result in carbon buildup. fuels which lack lubrication can also burn your valves - that's not really an issue here though.

You lot on here are so demeaning and do not lay yourself open to others learnings or findings or others opinions!

The thing is if you consider having things better to do than put the correct fuel in your motor than you yourself may be open to deserving burnt valves also.

95ron is dirtier than 98ron and will deposit the carbon around the neck of the valves affected ....the valve will then be restricted to opening properly which will give less clearance for the hot exhaust gasses and will burn the seat of the valve until part of it breaks off.....Nothing at all to do with a leaner mixture which can also cause burnt valves, this is another issue.

Also another issue is because one may be using the incorrect fuel for continuous running and of course it`s a turbo and the performance will be used then the ECU will retard the ignition because of poorer fuel and how does it do this?.......by the knock sensors bolted on the block.....and in between your more important things to do read post 16 and the malfunction of the knock sensors was probably caused by incorrect fuel being used and the knock sensors going overtime causing knock to continue.

Forgot to mention, have a look on your fuel tank cap and see if the sticker, if it hasn`t blown away by now, is still there and it will tell you what fuel is best to use!

I am not at all saying that this is the OP`s problem ...i was just trying to help another member see that using the recommended fuel on a turbo is the best way forward for reliability and performance.

[S70T5Chris]

Standard T5s can run on 95 quite happily.

Christ, that's like rocket fuel compared to the crap Americans run them on!

Remapped though, gotta be 98. I wouldn't even use BP's crappy 97.

That is incorrect. In Europe we measure our fuel ratings in RON, in the US it's MON (IIRC), which are not the same thing at all. And although the MON figures are lower than our RON numbers, it equates to the same octane fuel we have over here.

[S70T5Chris]

You lot on here are so demeaning and do not lay yourself open to others learnings or findings or others opinions!

The thing is if you consider having things better to do than put the correct fuel in your motor than you yourself may be open to deserving burnt valves also.

95ron is dirtier than 98ron and will deposit the carbon around the neck of the valves affected ....the valve will then be restricted to opening properly which will give less clearance for the hot exhaust gasses and will burn the seat of the valve until part of it breaks off.....Nothing at all to do with a leaner mixture which can also cause burnt valves, this is another issue.

Also another issue is because one may be using the incorrect fuel for continuous running and of course it`s a turbo and the performance will be used then the ECU will retard the ignition because of poorer fuel and how does it do this?.......by the knock sensors bolted on the block.....and in between your more important things to do read post 16 and the malfunction of the knock sensors was probably caused by incorrect fuel being used and the knock sensors going overtime causing knock to continue.

Forgot to mention, have a look on your fuel tank cap and see if the sticker, if it hasn`t blown away by now, is still there and it will tell you what fuel is best to use!

I am not at all saying that this is the OP`s problem ...i was just trying to help another member see that using the recommended fuel on a turbo is the best way forward for reliability and performance.

No one can argue with any of that. It's pure an simple fact.

It does amaze me how many people will use 95RON fuel (for the sake of saving a couple of quid on each fill up), and think that it is acceptable. I'm pretty certain it says on the inside of the fuel flap to use 98RON, even my ATR does!

I've said it for years, if you scrape on the little things, fuel type, tyres, which oil, which brake discs/pads.... what other aspects of your car are not up to scratch? You shouldn't be driving a 200+bhp car capable of 150+mph.

[Mart5in]

You lot on here are so demeaning and do not lay yourself open to others learnings or findings or others opinions!

The thing is if you consider having things better to do than put the correct fuel in your motor than you yourself may be open to deserving burnt valves also.

95ron is dirtier than 98ron and will deposit the carbon around the neck of the valves affected ....the valve will then be restricted to opening properly which will give less clearance for the hot exhaust gasses and will burn the seat of the valve until part of it breaks off.....Nothing at all to do with a leaner mixture which can also cause burnt valves, this is another issue.

Also another issue is because one may be using the incorrect fuel for continuous running and of course it`s a turbo and the performance will be used then the ECU will retard the ignition because of poorer fuel and how does it do this?.......by the knock sensors bolted on the block.....and in between your more important things to do read post 16 and the malfunction of the knock sensors was probably caused by incorrect fuel being used and the knock sensors going overtime causing knock to continue.

Forgot to mention, have a look on your fuel tank cap and see if the sticker, if it hasn`t blown away by now, is still there and it will tell you what fuel is best to use!

I am not at all saying that this is the OP`s problem ...i was just trying to help another member see that using the recommended fuel on a turbo is the best way forward for reliability and performance.

That's the answer I was looking for. :B_thumb: just in case anyone shows 'ignorance' like my previous post.

Out of curiosity, I did look inside the filler flap and it doesn't actually mention RON ratings, only to use unleaded.

However in the handbook it does say that:
"98 RON is recommended for maximum effect and minimal fuel consumption."
"95 can be used when driving normally."


I always fill up with 98 (usually BP), it's only an extra fiver or so plus I've had mine remapped.

[Doingitsideways]

Ah, my bad.
Didn't realise the American system was different. Should have known better, as they refuse to comply with the rest of the world in any unit of measurememt, even their gallon is different to everyone else's!

I was merely saying that regular unleaded is considered fine by even the manufacturer (sure I remember reading that in the handbook somewhere) and I'd think it fine for pottering around in a standard T5.

Modified though, even with a simple remap, I wouldn't even consider anything below 98ron.

As for your Type R Chris, they're a highly strung, tuned version of a standard engine to start with, made to be revved to the redline all day long, so hardly surprising Honda reccomend a strong shot of juice to run them on :)
A standard T5 is such an unstressed unit, even though it is turbocharged, it could probably be ran on dog piss :lol: