1st Gen R53 Cooper S Engine Pinging on acceleration at high rpms + engine running lean

I'm just waiting for the day...

when you realize that with all this stuff you think I'm right on about MINIs and engines, you realize that it extends to other "off topic" arenas as well....

Well, I'm waiting... But not holding my breath, if you know what I mean!

Matt

 

You and I can agree that neither of us will hold our breath waiting for the other to have that moment of revelation!

Unity! :cornut:

 

Hey Kam, I'm in LA myself... and have an auto. And a 17% and a tune. And the JCW (380) injectors.

Another factor is that we only have 91 octane gas in California.
Back when they removed 92 or 93 octane (i'm getting old, I forgot when) I was running a 300ZX twin turbo.

At that point, folks had a choice. Go to an aquamist setup, or turn down the boost.
While I'm no engineer, I do remember the major 300Z folks saying that at some point you had diminishing returns and no amount of fuel could support 16lbs of boost (on the Nissan engine, etc etc).

I'm pretty sure California has the WORST gas available in the nation.

And while I didn't go as far as to check coils, wire conditions, fuel filters, etc, my car had about 8k miles on it when it got it's first round of upgrades. And 12k when the 380cc (JCW) injectors went in.

And Blimey, my injector maps are still close to maxed out at some point on the RPM curve... hence the desire to switch to 550s and a tune that can handle them.

Who wants to send Kam and I some gas?

PS. With 100 octane in the tank, the detonation goes away on the JCW injectors. With the stock injectors it would STILL ping with 100% 100 octane in it.

 

Yep - octane can certainly be a factor.

Rooster - interesting that you're running close to the edge with your injectors...

I'm definitely not anti-big-injectors... I just don't think everyone needs them equally. You also need a tune that can accommodate them. And be sure the car never gets flashed back to a factory map. :devil:

 

Not to highjack the thread, but it's a 2008. Who knows if the factory made any changes between 06 and 08.

Jan did the best he could on the 17. I'm sure with a 15% everything would have been fine?

Or I just had lots of nice high compression. Or something.

Kam, we'll have to meet up and compare notes. What part of southern California are you in?

 

I'll be interested to see what they find out. Especially since our cars seem to exhibit similar symptoms... but again, mine did this with like 8k miles on it.

While brand new factory parts might have been causing issues, it's pretty unlikely.

Like I said, 100 octane and stock injectors would still ping. On the JCWs 100 octane is enough to keep the car quiet. Next stop (eventually) 550s.

 

KamG: here is some good info for your reading...

http://www.motoringalliance.com/forums/engine-drivetrain/2545-bigger-better-faq-bosch-550cc-injectors-r53.html#post43549

Normally, i'd suggest the 380cc ($200 to $250) if you do not planned to upgrade your car any more after this point (i.e. no cam or header or IC, etc)... But if you have the upgrade itch down the road, then the 550cc ($300 new) is the best bang for the dollar.

As a tuner, we can only make recommendation. Whether or not people take our advice is up to them. When we did the 17% pulley upgrade originally, i highly recommended that a tune be performed at the same time. But that was turned down so the car left with the factory tune on the 17% pulley installed. Then we made arrangements two weeks later for the dyno tune.

Typically we ask the customer ahead of time of what their goals are from the beginning so we can recommend a mod list that fits the budget.

Another thing to remember is that your car is 'live' - which means its parts do experience wear and tear. So the tune may have been a static state at any given point in time, but when parts wear out and deteriorate, the status of the car will change. In this case, it may be as simple as a bad set of spark plugs. But with the bigger injectors, new colder plugs and new coil pack/wires, your car will be running much safer with a tune to tie everything together.

We will get it all sorted out on the dyno tomorrow.

cheers.
mike

 

I know I've already said it on Motoring Underground, but real glad you got it figured out. I know you were at your wit's end.

 

In the end what was the exact cause?

 

As far as gas mileage goes are you basing that on what your onboard computer is saying or by just doing the math per tank load of gas ? With bigger injectors your onboard computer is thrown off quite a bit . I made that mistake when i put in 400 cc units and thought i was getting better mileage which was not the case .

randy

 

Sounds like he needed more fuel to be delivered. Autos in California with 17% pulleys don't seem to like pump gas. At least not on stock or JCW injectors.

 

We'll never know...

it's looking like the car was in a lean condition. But other cars with those parts don't always run lean. Whatever it was, going to higher capacity injectors and tuning for how the car is seems to have cured it. Whether it fixed the root cause or just compensated for an existing condition I can't see a way to know for sure.

Matt

 

But why was the fuel pump replaced. Was it diagnosed as not flowing enough, how was that diagnosis made?

It just seems that a lot of parts were tossed at this car in hopes to finding the culprit. Was a shotgun approach or were they replaced one by one.

 

the car was logged, it was showing over 20% lean
once the pump was replaced the fuel trims came back into line

 

Cool!

Good to know....

Matt