DS3 Racing Nightmare!!

[Chris_Blue]

And they kept phoning me up dropping the price too.
Good luck Heidi

[lfcrule1972]

Yeah I hope the meeting with the service manager resolves your issues one way or another heidi

[heidi]

Thanks guys - here's to 4.30, will let you know how it goes. Am gutted, I love my little racing but had a long chat with Jamie at SP this morning, his information is horrifying!

[heidi]

Well we had a good 30 minutes with the Service Manager, explaining our case which was that whilst the proposed repair of replacing of the inlet valves would resolve the issue in the short term, our research showed that there is a fundamental design flaw with the engine and that the problem would just come back! He agreed that the valves on my car were all coked up again and that the cleaning of them 6 weeks before had been unsuccessful.

You may be interest to know that the engine in the 155 is the same as the DS3R although doesn't run as hot, so has the potential to suffer the same problem. We told him as a result we wanted our money back. He asked if we would take a replacement vehicle, we said only if it was an equivalent in spec and performance, without the problems. He now has two weeks to find a solution and to get back to me.

[Chris_Blue]

Take the money....
155s arent as bad as all that

[Jonbays]

Well my THP155 suffered the carbonisation on the inlet valves and Citroen did remove the head and disassemble and chemically clean it all up. So not as confident that running hot has anything to do with it at all.

It will be more a combination of fuel injector placement, pulse modulation combustion chamber swirl characteristics and valve timing. The more aggressive (longer inlet duration) valve timing to produce more power the more likely the problem is of course.

[Czar]

Well we had a good 30 minutes with the Service Manager, explaining our case which was that whilst the proposed repair of replacing of the inlet valves would resolve the issue in the short term, our research showed that there is a fundamental design flaw with the engine and that the problem would just come back! He agreed that the valves on my car were all coked up again and that the cleaning of them 6 weeks before had been unsuccessful.

You may be interest to know that the engine in the 155 is the same as the DS3R although doesn't run as hot, so has the potential to suffer the same problem. We told him as a result we wanted our money back. He asked if we would take a replacement vehicle, we said only if it was an equivalent in spec and performance, without the problems. He now has two weeks to find a solution and to get back to me.

Well my THP155 suffered the carbonisation on the inlet valves and Citroen did remove the head and disassemble and chemically clean it all up. So not as confident that running hot has anything to do with it at all.

It will be more a combination of fuel injector placement, pulse modulation combustion chamber swirl characteristics and valve timing. The more aggressive (longer inlet duration) valve timing to produce more power the more likely the problem is of course.

I would be very interested to know more of your research which indicates to a fundamental engine design flaw, please share this information.

Just to clarify, all THP engines suffer the same carbon deposit build up in the air inlet tract, on the inlet valve stem, back of inlet valves and the valve seat, this is a direct result of there being no fuel present in the air inlet tract, with the absence of fuel to cool and wash the inlet tract and inlet valves.

Any oil molecules present in the air inlet stream will coagulate, this coagulation is rapid, with accelerated coagulation from the hotter than normal inlet temperatures, over regular port injection, this extra heat is a direct result, from there being no fuel present in the air inlet tract, to cool and wash the inlet tract/valves.

Furthermore, DI, GDI, FSI, TFSI, call it what you will, all direct injection engines, have the fuel injectors installed directly in the cylinder head roof chamber, this installation position allows for greater fuel control, before, during and after the combustion stroke, this fine fuel metering control gives you the end user, superior MPG, power and smooth running, albeit at the expense of oil particle coagulation from the hotter cylinder temperatures required to maximise fuel efficiency!!

Last note, all THP engines have a dual stage ECU map controlled electro thermostat, the primary running temperature is 105°c the secondary stage is engine load sensitive to prolonged heavy throttle use, and opens up the full cooling circuit, which reduces the running temperature to 85°c

[Superfly Guy]

I would be very interested to know more of your research which indicates to a fundamental engine design flaw, please share this information.

The most conceited statement ever.

[Dangerousfish]

The most conceited statement ever.

Which goes on to defend itself...

[Superfly Guy]

Which goes on to defend itself...

I disagree, it becomes a self indulging ramble that aims to put down a new member.

[Dangerousfish]

I disagree, it becomes a self indulging ramble that aims to put down a new member.

Maybe.

Maybe you're also reading too much into it.

Happy to agree to disagree.

[Chris_Blue]

Czars just a straight talking Techie SFG. He's a good guy, just not a diplomat. LOL.

[Czar]

I disagree, it becomes a self indulging ramble that aims to put down a new member.

My intention is not to slate a new member, or indeed anyone, I am here to help, offering correct straight to the point friendly advice, that said, when I read about any individual who is claiming to have undertaken research, regarding the THP engine, stating it has a "fundamental design flaw, then for the good of the forum, shouldn't this research information be shared, so we can all further understand, and possibly work on a solution, if there really is a fundamental engine design flaw!!

Czars just a straight talking Techie SFG. He's a good guy, just not a diplomat. LOL.

Thank you Chris, I never have been too diplomatic, LOL.

[cyclone]

There are definitely problems but would not say they are fundamental but implemental. Direct injection, which has a lot of benefits, like any technology advancement is experiencing problems but as new generations of engines come out the problems will be and are being overcome. Just as the problems with early engines were slowly overcome till we have the modern internal combustion engine that lasts hundreds of thousands of miles.

[Jonbays]

Well maybe emissions & performance were design parameters and engine service life before carbonisation rectification becomes necessary weren't design parameters so its not a design flaw! Just an expensive awkward service schedule that takes us back to the good old days of decoking two stroke engines.