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Discussion Starter #1
I am the second owner of a 2000 m5 with 210,000 miles. Recently, the car's power would suddenly cut when stomping on the accelerator. However, I could gently accelerate, but when I floored it, the engine felt like it was cutting fuel. The fuel pump was replaced 15k miles ago. No check engine lights (at least according to my Foxwell nt510 scanner). Car idles perfectly and starts easily. Helpful tips on what to look for next would be great.
 

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Discussion Starter #4
I replaced the MAF's and the problem is resolved. No more hesitation above 3k RPM. I'm surprised no faults were stored or pending in the ECU. Is this usually the case with MAF problems for s62's?
 

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Discussion Starter #5
Sadly, I spoke too soon. After a day of zero hesitation, the power cuts above 3k RPM if I hammer the gas pedal. I replaced the fuel filter and it made no difference. No engine faults stored. Rather than throwing parts at this, can anyone recommend some other potential cause?
 

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Check the fuel pump relay. Mine had similar symptoms and there was a small burn spot when the relay was opened up. You can either just replace the relay or direct wire the fuel pump and bypass the relay. CPS are another possibility.
 

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Discussion Starter #7
Just a quick note for anyone reading this thread that neither the new maf, fuel pump relay, or fuel filter solved the issue.
 

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How many miles on the car since replacing the MAFS? It make take some time for the ECU to adapt.
Can your scan tool read fuel trims?
 

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A look at the fuel trims could be helpful. Still no codes? How much fuel in the tank? If you have INPA you can view the trims and also monitor the TPS. They (TPS) can sometimes lose signal and cut out but generally they will set a limp mode and/or codes will pop up.
 

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This may sound basic but have you considered the stuttering as a result of the traction control kicking in? It's cold out and I find the TC working more frequently than in the summer.
 

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Had a similar problem with my beast. Power would dip dramatically in the upper rev range when stepping hard on the gas. In a short-term period, I replaced the fuel pump (following excellent DIY in this forum), all four CPS, and had previosuly replaced MAFs. In my case, none of these parts semmed to fix the issue.

It ended up being the clutch. Even though it felt good in normal driving, it was slipping in higher rpms. Replaced it and problem solved. Again, this was my specific case. Maybe your clutch is fine, but just something to look into before throwing money at parts that don’t fix the problem. Due to my car’s mileage, I don’t mind having replaced the fuel pump and CPS, but would have been nice to fix the clutch first and save the money for later.
 

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Good luck! Hope you figure it out!

Sent from my Pixel 3 XL using Tapatalk
 

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Discussion Starter #14
I think there is a good chance it's the clutch. I looked through all the records and I can't find anything that says it was replaced. I am the second owner and the previous seller had tons of records. Can anyone suggest which clutch kit to buy? Stay with the dual mass flywheel as well?
 

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I honestly don't think the clutch is bad based on your description. Typically a bad clutch will slip and you will get rpm climbing fast but no/less acceleration. If the rpm's climb more slowly when your problem happens, or has hiccups, stuttering with slow rpm climb, it's guaranteed not the clutch.

It's not 100% guaranteed test, but one way to test the strength of your clutch is to load it up in 5th gear at a slow speed and see if it slips.
 

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Pretty clear difference. Stomp on it fifth like Tim says. If the engine races and the car doesn't go it's the clutch. If the engine lags it's engine/fuel.
 

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I really do hate the new forum layout. Anyways, I would start by checking the live data and see if you have misfires when you accelerate. I recall few times my first M5 will cut out during WOT due to misfires for no reasons.

If you are local to central CT, I can help you diagnose the issue.
 

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Discussion Starter #19
You guys are probably right about it not being the clutch. But, I confirmed with the original owner today that it was in fact the original clutch and flywheel! I find that rather amazing after 210,000+ miles. What's even more surprising is that after removing the transmission today, the clutch disc still had meat on it. I'll post a pic. Should I throw out the flywheel? I'm assuming after that many miles it should be toast.
 
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