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lately, I've been feeling like the m5 is lacking power. took my peake code reader and only received the ebox fan code 8f. I'll be fixing it soon. My question is, will intermittently failing CPS and MAF trigger a code? I only started to drive my m5 more because my wife took my rx300 SUV after an unfortunate accident of her e46 ( love that car, and wife is unharmed). What I've done so far is clean MAF and the Dinan filters (K&N filter cleaning kit and hopefully did not over oil)

I'm thinking i'm just itching for more power since I've been eyeing Evolve headers, X pipe and jail break tune. Anyone in Houston Southwest Texas that can compare cars?
 

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You're probably used to it. I test drove a 986 Boxster S a few weeks ago and when I jumped back in the M5 it felt faster than it did before.

For what it's worth, chances are you'll always get used to the power short of something absolutely outrageous.
 

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You're probably used to it. I test drove a 986 Boxster S a few weeks ago and when I jumped back in the M5 it felt faster than it did before.

For what it's worth, chances are you'll always get used to the power short of adding a supercharger kit.
Fixed for you!:biggrinbounce:

Regards,
Jerry
 

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From time to time, start off on a highway on ramp and stay in 2nd gear starting off fairly slow. Get up to around 4-5k rmp and mash the throttle and run thru the gears, you will feel the power even if you have gotten used to it.

Also, looking out the front glass always seems like things arent coming up very fast. When you are at speed, and still on the throttle, and your surroundings are safe, take a look in your rear view and you will see cars disappearing faster than you expect.
 

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From time to time, start off on a highway on ramp and stay in 2nd gear starting off fairly slow. Get up to around 4-5k rmp and mash the throttle and run thru the gears, you will feel the power even if you have gotten used to it.

Also, looking out the front glass always seems like things arent coming up very fast. When you are at speed, and still on the throttle, and your surroundings are safe, take a look in your rear view and you will see cars disappearing faster than you expect.
Just remember to let off the throttle if the other cars are suddenly upside-down. :3:
 
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My car threw no codes but felt like power was down. I originally thought it was me getting use to it but after four new CPS and two new air filters, she rips hard. It felt exactly like the first time I drove the M5.

So it could very well be some old parts needing attention but not quite completely dead. This acceleration isn't that easy to get use to. It is quick.
 

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lately, I've been feeling like the m5 is lacking power. took my peake code reader and only received the ebox fan code 8f. I'll be fixing it soon. My question is, will intermittently failing CPS and MAF trigger a code? I only started to drive my m5 more because my wife took my rx300 SUV after an unfortunate accident of her e46 ( love that car, and wife is unharmed). What I've done so far is clean MAF and the Dinan filters (K&N filter cleaning kit and hopefully did not over oil)

I'm thinking i'm just itching for more power since I've been eyeing Evolve headers, X pipe and jail break tune. Anyone in Houston Southwest Texas that can compare cars?
Your problems are two fold (at least).

Firstly, you are likely getting used to the power and the initial thrill is not there any more. To fix this, as Dirty Harry posted, drive a different car for a while. A less powerful car or at least one that makes its power differently. The e60 M5, for instance, is more powerful but the way that the s85 makes its power is a completely different sensation. The S62 has a lot of low end torque and subsequently it fells like you're being shoved into the back seats. The S85, on the other hand, lacks the low end torque and the sensation is (like being swept along by the hand of god) less of power and more of speed.

Secondly, there may be some underlying issues. A CPS or MAF that are failing (within operating limits most of , but not all of the time) will not always set a MIL, unless the fault is present long or consistently enough. Also, oiled filters are not good for the MAF's longevity.
 

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my problem is the other car I drive a lot is quite a bit faster than the M5, so that makes it feel even slower!

But that is very easily cured by hopping in the E34 525i or the Mazda 4 banger!!
 

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"Drive another car" is right on. It was the same when I rode sport bikes as daily transportation.

I too, get to feeling, "What's wrong with this car? It used to be so much faster!" then I drive my wifes Maxima for a few days.

Get back in the M5, mash the throttle and I'm smiling ear to ear all over again.
 

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Just dont do the opposite and drive a faster car, then get back into your M5 :p
 

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I've driven many muscle cars and jigher HP/TQ cars. You get used to anything...it's why we try to improve our lives.
You'd "get used" to dating a supermodel too.

What the M5 does that others don't is provide that "torquey surge" through the gears. Really feels like old school big block. Stock mufflers have deep growl as well.
Sure...I could bolt on a CF S/C kit, and may do so when I save up $6k but even stock this thing is FUN.

That said...you may have lost power. Over oiling your filters is akin to choking your intake.
Also, if the weather gets above 85deg it could heak soak yr engine.

I must say...this M5 even in 80-85 degrees is amazing at giving power under heat load. It kicks my Mustangs butt and I think they both had alum heads/block.

Used to it? Yes.
Boring? He!!z no.
 

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OP, if you're coming out of an RX and can't feel the difference, something about the M5 is seriously amiss.
 

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I'm having this issue with mine in the heat. I've replaced everything and have done the IAT relocation and have since gone alpha-n. Cold out, fast and fun. Anything over 85 degrees it becomes a pig that V6 mustangs keep pace with. It will cut all power on full acceleration when hot (always drive with DSC off and run 91 here in CA). It's becoming very aggravating.

I have zero codes, I constantly check VANOS operation via GT1 (great btw), pass all L/h tests (Test 4.2), new thermostat and radiator keep it between 79c-90c and have no other sensors, vacuum lines, or filters to replace.

To answer your question yes you can have engine difficulties with no error for the CPS sensors, however as another member mentioned in another thread, it will usually eventually show itself as an error. MAF will not always throw a related code.
 

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I'm having this issue with mine in the heat. I've replaced everything and have done the IAT relocation and have since gone alpha-n. Cold out, fast and fun. Anything over 85 degrees it becomes a pig that V6 mustangs keep pace with. It will cut all power on full acceleration when hot (always drive with DSC off and run 91 here in CA). It's becoming very aggravating.

I have zero codes, I constantly check VANOS operation via GT1 (great btw), pass all L/h tests (Test 4.2), new thermostat and radiator keep it between 79c-90c and have no other sensors, vacuum lines, or filters to replace.

To answer your question yes you can have engine difficulties with no error for the CPS sensors, however as another member mentioned in another thread, it will usually eventually show itself as an error. MAF will not always throw a related code.
Throw in a can of Torco Accelerator (octane boost) and let us know if there is a noticeable difference under similar weather conditions.

Regards,
Jerry
 

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Throw in a can of Torco Accelerator (octane boost) and let us know if there is a noticeable difference under similar weather conditions.

Regards,
Jerry
I know this will ease heat related issues. I use 100 octane in my 13psi supercharged E36. I feel like it is a bandaid solution to have to constantly fork over $20 per fill to make the S62 run like a new 5.0 mustang does in any weather on pump.

Keep in mind I have two E39 M5's in my household, both 01's. The other one, completely stock, doesn't have this significant loss in power.
 

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I put down 354 whp and she feels slow to me! As a matter of fact I argued with George after he adjusted timing that she was still locking power. I have everything new on my car short of bottom end!

So, get your maintenance done all sensors, filters including fuel filter where I also changed pump, relay, filter FPR, the vacuum line going from FPR to the motor. I did my CPS, TPS, MAFS, O2's, and on and on and on. I still said she's down on power! So with the motivation of this wonderful board and it's even more amazing members I went to a dyno and put down 354 whp with only xpipe, SS race cans and that's it!

So you see with 354whp I'm used to it especially that I owned some high hp cars. Get her to the dyno ASAP. Dyno jet if you can.

Good luck!


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