Total and sudden power loss at WOT - help w/ diagnosing




There are three variants of the fuel filter; you either the first (211-470-24-94) or the second (211-470-51-94) variant as the third variant (211-470-64-94) requires an adapter cable to the connector on the top of your photo. If that filter has more than 60,000 miles on it, you're on borrowed time. Not if, but when the restriction is bad enough the pumps over-current and melt the fuel pump relay.
Be advised the updated fuel pumps require the third variant of the fuel filter because the fuel line connections between filter and pumps are different from earlier versions. You should hang a fuel pressure gauge on your fuel rail and tape it to the windshield so you can monitor fuel pressure at WOT.
Also note the compressed foam insulation on the fuel pump connector; that's from the metal lid pressing down on the harness and is a potential short circuit. With the new fuel pumps you should also obtain the foam cushion that sticks to the underside of the metal lid; this foam provides an additional measure of safety to prevent the harness from shorting against the metal lid. As the current draw increases, the heat will literally melt the plastic at the connector and cook the insulation off of the harness where it flexes.
But, as I mentioned in an earlier post, the dealership confirmed that my car was eligible for the warranty extension and will perform the tank repair as soon as the weather and road conditions permit here in Quebec. I have until Aug 2018 to show up there.
So I assume they will replace the whole thing, including sender unit, pump and tank, unless your guys know otherwise?
Let me know
Last edited by lockeed; Apr 10, 2018 at 02:46 PM.
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ECU tune installed easily and the pulley too. One thing I'd like to get your feedback on, I went for a test drive after the install and the car had a very hard time pulling as it should. It almost felt like my first symptoms which was rapid sputtering, but different... No CEL or codes at all this time. And other times, it seemed to grab properly and deliver the power. I didn't hear any slippage but it would be quite hard to hear at full throttle anyway, especially with headers.
If I had to guess, I'd say the sc belt was slipping (the original belt, not the shorten one I'm waiting on), which caused the SC to underboost quite a lot. Seems logic. Side note, my tensioner is brand new. When I came back to the garage, I found there was a burnt odor floating around, which probably came from the belt or the sc clutch...
One other thing, when I removed the original pulley, there was some light corrosion as well as (what I thought was) medium grooving in the clutch plate. I sanded it and it turned out quite nice (see before/after shots bellow). But since the car has 266K kms, I'm wondering if the plate is causing the new pulley to slip more than the oem belt is? What do you guys think?
I also grabbed a couple pictures while I monitored the short-fuel sys 1 and 2 at idle, then i did a quick video from idle to about 3.8k showing the SHRTFT 1 and 2, MAP and RPM if it can help any of you pinpoint the problem. Let me know if other data would help
As always, thanks!
Before
After
At idle
Last edited by lockeed; Apr 14, 2018 at 08:10 PM.
No, I don't have the correct belt on there, I'm still waiting on it from VRP. Actually, they never confirmed they got my message about the missing belt! I guess they will next week...
So if it is the belt slipping, it's probably just due to the OEM belt which would make sense.... although I read some guys ran the oem belt with not much issues... and yes, I got the 76mm pulley
I'll remove the pulley and inspect it to make sure it's properly seated, and remove the spacers I guess... I'll be a start.
I saw someone suggesting you grind the clutch plate on higher mileage cars by 1mm, then adjust with spacers to get the 0.35 to 0.45mm clearance. Make any sense?
Back on the pulley, I tried to remove it and I couldn't get it out from the shaft. It seems to be grabbing the shaft quite a lot more than I remember. (might be just me). And looking at the outer portion of the pulley, it doesn't seem to be fully seated where it should on the shaft as well. Pretty sure the whole thing could slide in a little bit and gain the missing .40 to .50mm to get within spec... I tried hammering it lightly flat washer that goes above the bearing to see if it would move in... it didn't. But pushing and pulling the pulley on the shaft has proved very hard, even if I lubed it with bearing grease before putting it on.
tell me what you think on this:
Last edited by lockeed; Apr 14, 2018 at 09:29 PM.
Id avoid grinding the clutch magnet personally, but have no expertise/knowledge about that but maybe its fine. My thought is if you grind it down you make the total mass of the magnet less so less powerful magnet??
That was my exact thought.
At the moment, I can't get the pulley out, so I'l need to start pulling on it more aggressively I guess... I tried to pry it off with a flat head between the clutch and the pulley but I don't want to wrap it or risk breaking it... It's just very tight on there and yanking it out doesn't seem to work....
1) I could barely turn the bearings while I held the VRP pulley in my hands
2) I had aprox 1 full mm of clearance between the clutch and pulley, which is at least 0.60mm to .70mm more than where it should be (.35mm / .45mm)
3) the VRP pulley uses two bearings with a spacer in the middle instead of one large bearing
4) the overall depth of the bearing seat on the VRP is aprox 0.75mm MORE than the original pulley, or about what I need to gain to get within specs which make sense. Which also tells me the pulley was machined with incorrect tolerances.
Since the bearings and mid spacer were so tightly packaged in there, I filled aprox 0.2mm off of the spacer to alleviate the pressure - which instantly enabled me to turn the bearings manually as they should. I could always file the spacer more but it would then create a slack which would enable the pulley to move on the longitudinal axis.
With this simple mod, I was able to get down to aprox 0.70mm clearance all around, again, measuring clearance isn't a perfect science, how much to you press on the gauge? How hard should you press to slide it in as there is some play on the clutch plate...?
So this is where I am now... I went for a test drive (still with the incorrect belt on as VRP didn't put it in the package) and the symptoms haven't changed. Still hesitation and sputtering at high load.
With this simple mod, I was able to get down to aprox 0.60 to 0.70 clearance all around, again, measuring clearance isn't a perfect science, how much to you press on the gauche? How hard should you press to slide it in as there is some play on the clutch plate...?
So this is where I am now... I went for a test drive (still with the incorrect belt on) and the symptoms haven't changed. Still hesitation and sputtering at high load.
Feels free to suggest anything. Pictures to come tomorrow...
Last edited by lockeed; Apr 15, 2018 at 12:52 PM.
I received the shorter belt from VRP, installed it - same thing. Car stills jerk and sputters under WOT (even 1/2 throttle sometimes).
I since filled the car up with gas and I now have a strong gas smell in the car. I'll take the rear seat off asap to check if there's any fuel leakage in the pump and sender area. I now feel pretty confident that this sputtering is caused by fuel starvation for a couple of reasons:
1) No CEL
2) under normal driving condition, engine runs fine so I eliminate the coils as possible suspect.
3) one or more injectors might be faulty, but it usually doesn't feel like that when it's on his way out, and I assume it would drive like crap under normal condition and acceleration, which my car doesn't.
Let me know what you guys think. I think i'll drive the 650km to get it all replaced under the recall as soon as I can... Might just solve the problem once and for all.




I received the shorter belt from VRP, installed it - same thing. Car stills jerk and sputters under WOT (even 1/2 throttle sometimes).
I since filled the car up with gas and I now have a strong gas smell in the car. I'll take the rear seat off asap to check if there's any fuel leakage in the pump and sender area. I now feel pretty confident that this sputtering is caused by fuel starvation for a couple of reasons:
1) No CEL
2) under normal driving condition, engine runs fine so I eliminate the coils as possible suspect.
3) one or more injectors might be faulty, but it usually doesn't feel like that when it's on his way out, and I assume it would drive like crap under normal condition and acceleration, which my car doesn't.
Let me know what you guys think. I think i'll drive the 650km to get it all replaced under the recall as soon as I can... Might just solve the problem once and for all.
1) Just came back from the dealership where they replaced the fuel tank, pumps, level/sensor etc... all under the warranty extension.
2) I just received my replacement plug wires so I installed them this afternoon.
So just to be clear, car also has:
New Plugs
New engine mounts
New transmission mount
New oil and filter
New valve cover gaskets and fresh caulking
New sec. belt
New sec. belt tensioner
New VRP Pulley & tune
New Headers
New air filters
New Bosch 010 pump
Car is under second transmission oil flush, 1 remaining along with new filter and pan seal to be installed.
Went for a test drive - car still has roughly the same hesitation under 1/2 to WOT. Since they replaced the pump, I have the impression that the power is more instantaneous than before... but this car plays trick on you. Other than being pretty discouraged... it still feels to me like belt slippage OR ignition related OR injection related. And has it did in the past, car will sometimes grab and pull like crazy in 2nd or 3 gear, then when it changes gear, it loose power and starts to bog again. It still pulls but it vibrate and feels 250hp down.
Suggestions welcome. Car has no CEL by the way.... if only...
ps, I also noticed a belt squeal when I lift the throttle after a strong pull, car didn't really do that previously. Would a belt wrap kit alleviate that?
Last edited by lockeed; May 26, 2018 at 09:52 PM.






