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Tweaks For Better Economy?

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Old May 11th, 2021, 17:22   #21
Exasperant
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Originally Posted by tofufi View Post
Interesting you say that Dave. My 340 turbo has a 'used' lambda and returns mediocre fuel economy... could also be due to gearing and being fun to make progress

What readings would you expect from the Lambda/how to test?
Curiously, when I bought my MG it turned out the lambda was just the shell, any sign of sensor had long since gone - And aside from emissions fail it drove just the same, no noticeable mpg difference either, before and after fitting a new one.
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Old May 11th, 2021, 17:26   #22
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I'm surprised you've not had a car with a knock sensor before, almost all cars from the mid-late 80s had them.
I might have a history of mostly driving things pre-mid 80s. Or pre 80s at all. Hell, I've only recently moved from carbs to injection!
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Old May 11th, 2021, 18:20   #23
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Curiously, when I bought my MG it turned out the lambda was just the shell, any sign of sensor had long since gone - And aside from emissions fail it drove just the same, no noticeable mpg difference either, before and after fitting a new one.
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I might have a history of mostly driving things pre-mid 80s. Or pre 80s at all. Hell, I've only recently moved from carbs to injection!
Depending on the age of the MG it will have MEMS or MEMS2 engine management, i'm guessing ZR/S/T so most likely to be MEMS2 - either way both will have knock sensors and if they detect a failed sensor, will put a substitute value in to keep the engine running fairly sweetly.

You may not notice the improved mpg for a while with a working sensor but it will improve, MEMS in all its incarnations is slow to learn new sensors or even relearn after a flat battery - often it can take hundreds if not thousands of miles to get back to where it should be although it's meant to relearn within 200 miles of mixed driving.

If you've just moved to injection from carbs, there will be a lot of things to learn, especially on a Volvo!
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Old May 11th, 2021, 21:01   #24
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I’ve got a load of this in the garage

https://www.eurocarparts.com/p/tripl...yABEgKIevD_BwE

Will this suffice for the ATF U additive prior to me after an oil change?
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Old May 11th, 2021, 23:56   #25
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I’ve got a load of this in the garage

https://www.eurocarparts.com/p/tripl...yABEgKIevD_BwE

Will this suffice for the ATF U additive prior to me after an oil change?
Having had a bad experience with some Triple QX engine oil (i'm using the last 5L for oil blacking, won't even use it in my lawnmower as it even made that sound worse and a pig to start!) i'd be reluctant to say yes, but on paper it's very similar to ATF-U.
However it was tested in a Honda a few years back (it claims Honda ATF Z-1 compatibility) and was proven not very good. Went very thin quickly. As such, i'd not use it myself for anything.
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Old May 12th, 2021, 06:11   #26
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Cheers Dave
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Old May 12th, 2021, 15:19   #27
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Depending on the age of the MG it will have MEMS or MEMS2 engine management, i'm guessing ZR/S/T so most likely to be MEMS2 - either way both will have knock sensors and if they detect a failed sensor, will put a substitute value in to keep the engine running fairly sweetly.
Mk1 F VVC (you can see why I've bought something bigger and floatier to go alongside..) - I thought only the posher/ k V6 engines had the sensor, certainly that's what the internet generally claims? I'm tempted to plug the diag box in later now out of curiosity :-)

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If you've just moved to injection from carbs, there will be a lot of things to learn, especially on a Volvo!
First thing I learned when I got an F was "Be thankful for enthusiasts who reverse engineer the code reader kit, because a good ear, points file, and something to free off the mixture nut on an SU isn't going to cut it"

Which reminds me, is there anything similar for this era of Volvo?
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Old May 12th, 2021, 15:46   #28
Laird Scooby
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Mk1 F VVC (you can see why I've bought something bigger and floatier to go alongside..) - I thought only the posher/ k V6 engines had the sensor, certainly that's what the internet generally claims? I'm tempted to plug the diag box in later now out of curiosity :-)



First thing I learned when I got an F was "Be thankful for enthusiasts who reverse engineer the code reader kit, because a good ear, points file, and something to free off the mixture nut on an SU isn't going to cut it"

Which reminds me, is there anything similar for this era of Volvo?
I'm fairly certain the early K series had the knock sensor, can't quite remember my years but i think the F was 95-98 then repalced with the TF? You're lucky you've found a reverse engineered code reader, they're notoriously scarce!

When you say anything similar for this era of Volvo, i assume you mean some form of diagnostic kit?

If you lift the bonnet, you should find two small black boxes near the left hand suspension turret and bulkhead. Yours should be the LH-2.4 system so follow the destructions here for it :

https://www.volvoclub.org.uk/faq/EngineOBDCodes.html

As you'll (hopefully) find, a built in code reader! Be warned though, some faults can cause other codes to be generated so always worth a post to double check - for example a failed fuel pump causing an FTP will often throw a MAF or AICV code, sometimes Lambda sensor as well but not often.

Perfectly logical reasons for this - the system can't tell a failed fuel pump but it can tell that despite the ECU telling the AICV to open the engine spped and flow through the MAF hasn't increased, therefore one or both must be faulty - according to the ECUs limited "thinking".
In truth, the engine can't increase speed because there's no fuel getting through! Likewise it's getting no signal from the Lambda (which only works hot so the code only appears on a hot engine usually) so it assumes that isn't working either.
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Old May 12th, 2021, 16:51   #29
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Make sure tyres fully inflated, don't carry excess weight (clean out the boot) and all the above.
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