Unleaded Vs Super In 3-Row Mi16

[Tom Fenton 1,541]

Interested in anyone elses views on this.

My Miami Mi16 is on 3 row ECU with a knock sensor.

A week or so ago I was out in the sticks so put some normal unleaded (95) in it.

Didn't notice a difference initially.

However last night driving it to the Derbyshire meet and it just felt it had lost a little of its edge. Started wondering as you do if there was a brake dragging or something like that.

Anyway on the way home only about 1/4 tank left so dived into a Esso station and put some Super in. I was going to fill until I looked at the price, 122.9p/L!! HA.

 

Anyway having put the super in I set off back on to the dual track, bloody hell it really felt like a different car.

 

Now I know the knock sensor can alter the timing to cater for fuel, but I was suprised how different it felt straight away.

 

Just interested in anyone elses experiences.

[allanallen 528 2 Cars]

From a recent experience with my 205, 95 octane fuels seem to differ massively!

It normally runs ok on it but I put £20 in at morrisons(I think) and it had a job to go! Coughing and spluttering, was awful.

[nomis 12]

I'm interested in a similar question.

 

Got told my 1.9 GTI was pinking and needs a tune up (which I am going to do) but am wondering whether using Super fuel might solve some of the problem.

 

I must admit, I always though super fuel was a bit of a con but had a brief look into this on the interweb and it seems like for a GTI it could make a difference.

 

Do I need to use all the existing fuel in the tank before I top up or will doing it with about 1/4 full help?

 

(My car is standard except for a K&N induction kit fitted by a previous owner.)

 

Found this video on the topic which did a decent job.

[grandos 16]

Always put optimax now v-power as I figured out a few years back that it just seems to run better across the rev range no flat spots and also feels a little keener! (If that's a word)

Not a mind blowing difference but it is noticeable!

This however is not the case with modern cars!

[Simes 248 2 Cars]

My old 3 row, knock sensor Mi16 idled and ran better on 95......

[Simes 248 2 Cars]

I'm interested in a similar question.

 

Got told my 1.9 GTI was pinking and needs a tune up (which I am going to do) but am wondering whether using Super fuel might solve some of the problem.

 

I must admit, I always though super fuel was a bit of a con but had a brief look into this on the interweb and it seems like for a GTI it could make a difference.

 

Do I need to use all the existing fuel in the tank before I top up or will doing it with about 1/4 full help?

 

(My car is standard except for a K&N induction kit fitted by a previous owner.)

 

Found this video on the topic which did a decent job.

 

Original 1.9GTI's were designed to run on leaded, which was 97octane.

Most retard them to run 95, but 98 is best.

[kyepan 291]

My three row mi ran fine on both, it mostly lived on 95 though

[Anthony 1,003]

Peugeot specified that D6C 1.9 Mi16's needed 97RON minimum and weren't officially sanctioned for 95RON, although they have always subjectively seemed fine on it with no pinking I could hear on both 2 and 3 row management.

 

Is the engine standard Tom or has it perhaps had a heavy skim or running a #4 inlet pulley (thus increasing dynamic compression) that might explain the knock sensor pulling the timing back on lower grade fuel?

 

Could just be a bad tank of fuel as Allan says - certainly I've had it where I've filled up with supposedly the same octane and it's pinked badly after filling (1.9 8v Jetronic, so no knock sensor to pull timing)

[toolie72 67 1 Cars]

1.9 gti 8 valve-years ago when leaded was being phased out I went to local Peugeot dealer to find out what Peugeot themselves said-in short car was safe to run on unleaded but keep using higher octane (was leaded at the time) as it would run better

I always run tesco momentum (99ron) and car does run better-not necessarily faster but less of a pain in bum when town driving

[kyepan 291]

so yeah, now i've read the original post, somehow i missed that on my mobile, mine always ran smoother and quieter on 97, it also got better cruising MPG. Both I'd attribute to the ECU winding on the advance and listening for knock. The sound goes from a slightly noisy mushy fizzy sound to a crisper quieter note.

 

I actually ran it on 95 mostly because it sounded angrier... even though it was probably producing less power burning less efficiently.

 

It's weird that even without a knock sensor, when the itbs are running well, they also sound smoother, quieter and crisper, vs the same mushy fizzy noise when not.

[Tom Fenton 1,541]

Ok so some interesting comments but no definitive answers!

 

The engine came in the car, supposedly rebuilt a few years ago by DES Developments and has fast road camshafts in, certainly it feels a pretty strong example of an alloy Mi16, not sure what pulleys or compression it is though.

[welshpug 1,657]

afaik the Lambda equipped Mi16's were the lower compression engine, if it has cams it'll be leaner and run edgy on lower grade fuel.

[Anthony 1,003]

3-row management was far more common without lambda here in Blighty given that the majority of our Mi's were the full-fat non-cat 160hp variants.

 

The lambda equipped (148hp) 3-row ECU is 0261200161 whereas the non-lambda (160hp) 3-row ECU's are 0261200354 and 0261200355.

[Tom Fenton 1,541]

Its a D6C engine so high comp 160bhp and full fat management. I was just suprised to the extent it seemed to change when on 97, my Dads Quattro turbo is noticeably different between 95 and 97 but I would expect that with forced induction as they are obviously a lot more sensitive to knock and fuel octane.

[nomis 12]

Was going to go fill mine up with high octane this evening to test it out on the standard 8v and report back on whether there was any improvement.

 

One small problem... It's as dead as doornail. Suspect I may need a new battery.