Restoring older cars lost power

obi_waynne

obi_waynne

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Deal, Kent UK
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A3 1.4 TFSI 150 COD
As a car gets older the power is generally reduced. There are a number of factors in play here and general wear and tear cannot be easily reversed.

However I think we should focus on the things you can do to restore the cars "missing" power.

My first proposal is the fitting of new injectors. Even if you use good fuel they will deteriorate with age and a set of new injectors can do much to lift the engine back to factory settings.

I'm also of the school of thought that older engines loosen up and get better if they are properly looked after, anyone else subscribe to this thought?

So what would you recommend to get a car back to factory spec?
 
Engine build specification needs to be within tolerances, bottom end through to camshaft timings. Also cam profiles wear so lift is lost. Engine sensors need to be within working parameters so as to function correctly. Spark plugs are another item lost on some folk, can't see them, must be okay. But then the engine is just one part of the equation here, drivetain losses are not thought about when taking at the wheels figures, you need to take at the flywheel to see if the losses are through the drivetrain due to wear etc.

Some engines do actually work better with many miles on them. When I was racing the Audi GT back in the early 90s and developing the engines we found that a rebuilt engine using new shells seized up very easily. We ended up buying engines that had done in excess of 100k miles and stripped them, checked dimensions, wear and rebuilt them using the original shells and these never blew or lost power. The proof we had was when we purchased an ABT 2.4 turbo bottom end (ready to run), this did approximately 2 laps of Goodwood and seized, bent the crank. Went like stink before it decided enough!

My MG KV6 engine is getting better with age, at 86k it still pulls and the rolling road graphs tell me it's very healthy with the expected drivetrain losses, it'll go on for a long time yet. Regular servicing will pay dividends at the end of the day.
 
Aside from a full rebuild/overhaul, there isn't much we can do. Sure proper maintenance will make the losses less severe but cars/parts now are designed to break after certain periods no matter how well they are cared for.
 
It's a tricky one really, to be fair how many miles an engine/car has done really isn't an indictation of the condition of the engine, I are say that my 205's engine is down on power simply because it hasn't ever been used or even given a damn good thrashing once in a while, however since owning it I have chucked some injector cleaner in it and i also put about 500ml's worth of engine oil in with the fuel and after warming it up properly and taking it out for a proper run it seems tobe a bit better. I would say though I'd need to put some of my fully synthetic goop in next time I change the oil, will probably use an oil flush on it as it most likely has a semi synthetic in it.
 
Wcnwzrd said:
Aside from a full rebuild/overhaul, there isn't much we can do. Sure proper maintenance will make the losses less severe but cars/parts now are designed to break after certain periods no matter how well they are cared for.
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WELL said. Cars/Parts are designed to break after certain periods
 
jarrus said:
It's a tricky one really, to be fair how many miles an engine/car has done really isn't an indictation of the condition of the engine, I are say that my 205's engine is down on power simply because it hasn't ever been used or even given a damn good thrashing once in a while, however since owning it I have chucked some injector cleaner in it and i also put about 500ml's worth of engine oil in with the fuel and after warming it up properly and taking it out for a proper run it seems tobe a bit better. I would say though I'd need to put some of my fully synthetic goop in next time I change the oil, will probably use an oil flush on it as it most likely has a semi synthetic in it.
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I REALIZE THAT THIS IS AN OLD SUBJECT BUT I would never ever put 1/2 litre of engine oil in my tank as it would contribute to carbon build up and increase the chance of detonation especially in a high compression or turbo motor.
There are proper upper cylinder lubes and injector cleaners that are made for exactly that.
FWIW I use PROMA products in my turbo diesel 4by and wife's Accord every fill.

Here you go http://www.pro-masystems.com.au/DepartmentProductMenus/Performance/FuelAdditives
 
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Risk detonation? On a diesel engine? With respect, are you familiar with how diesel engines work?
And besides i did seek advise before doing so.... using a mineral oil in small quantites or even a two stroke oil in with diesel fuel adds lost lubrication that sulphur used to provide before LSD was introduced...theyre are plenty of studies that confirm this and has found to be much better than any off the shelf diesel treatment
 
jarrus said:
Risk detonation? On a diesel engine? With respect, are you familiar with how diesel engines work?


And besides i did seek advise before doing so.... using a mineral oil in small quantites or even a two stroke oil in with diesel fuel adds lost lubrication that sulphur used to provide before LSD was introduced...theyre are plenty of studies that confirm this and has found to be much better than any off the shelf diesel treatment
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With respect can you show me where "diesel motors" was mentioned in the actual post and not the sidebar as can't seem to see it anywhere in the posts ???? and yes I do understand how diesels work.
Can you post up the link to the "studies" you mentioned and the "off the shelf products " used in the studies you refer to please??
The PROMA products have been independently tested by A Qld university and the results written and signed off by their engineers.Can send the link if you want?

Yes I did note TD in your tag on the side however Diesel was not named in any of the treads.
 
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But he doesnt say its petrol either so since it says my 205 in the quote and his tag says 205 1.8 TDi a reasinable conclusion would be...........................
 
SLEEPER said:
But he doesnt say its petrol either so since it says my 205 in the quote and his tag says 205 1.8 TDi a reasinable conclusion would be...........................
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One needs to be a bit more specific so there is no possibility of confusion. I have both petrol & diesel fueled cars and he may also have both or are they only diesel fuel only ??
FWIW I have spoken to a BP chemist today and he says that they DO NOT recommend adding engine oil to fuel as it does not burn clean,adds to pollution , carbon build up and an absolute no no if there is a DPF fitted.
TD is only in the tag NOT in the post but always happy to be corrected if can be shown wrong .
I have only listed 1 car in my tag BUT have 3, 2petrol &1 diesel and am sure that there are many here with similar numbers or more in their garage.
PS reasonable .I can be a bit anal/pedantic about details LOL
 
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http://www.pug306.net/index.php?pageid=twostroke

I only have one car and its a diesel,
I sort the advise of a diesel specialist in peston called "diesel tuning bob" they do diesel engine tuning and maintanance and also rebuild injection pumps and run them on there test bench, they also deal with inline injection pumps like those found on merc diesels aswell as VW PD systems and modern common rail engines, these guys know there stuff when it comes to diesels and there knowledge comes from expiriance and testing,
As for the study ive no idea who conducted it but it was posted on another forum...(see top of post, my phone is being a pain) from the looks of it though it was done in the USA and was done independantly
 
@ TCJ -Why should diesel have to be specified?

Why assume we're talking about petrol cars?

Especially when over 70% of new cars sold here are diesel powered.
 
HDi fun said:
@ TCJ -Why should diesel have to be specified?

Why assume we're talking about petrol cars?

Especially when over 70% of new cars sold here are diesel powered.
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Because over here we had a TD Cortina that was only petrol powered and as of now we have a Holden Cruise with the initials with a "D" in it that is petrol powered and it is also available in diesel with a "D" in the model designation.Confusing isn't it :blink:
Guess that if jumping to conclusions was in the Olympics then I would win a gold medal LOL

PS Jarrus thanks 4 the link. Interesting results.
 
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