hoping someone can help me out, the car has a shudder/stutter, at part throttle (very light acceleration) at around 1500 rpm. When it starts to shudder it will continue even through gear changes, I can get it to stop just by rolling on the throttle more aggressively. And it is intermittent. Any ideas what might be causing this.

No issues whatsoever with WOT acceleration. (other than the boiling tires)

No CEL, only get one randomly for low evap leak (figure it is fuel tank related) Scanned entire car with my DAS, and it found nothing either.

I am taking it in Thursday to get Tank and Fuel Pumps replaced under the extended warranty.

Car just hit 100K this week I have had the car for a little over a month now and has done it since I got it. I was planning on doing plugs and coils in the very near future since it hit 100k.

It has a pretty indepth service history, my SA gave me an 11 page history on it when I took it in to request the Warranty repair.

Thanks again guys.

 

I vote plugs

 

Plugs. Seems like when they start missing it's always at low rpm under load. Next it will be at idle.

 

Ok my next question... I know stock plugs are NGK. I have always been a BOSCH guy. what does everyone else use/recommend. I believe everything right now is stock.

Thanks,

 

I think stock can be either NGK or Bosch? Correct me if I'm wrong but either way I think you'd be fine.

 

Stock NGK if you are staying stock. 1 step colder NGK if you plan to mod.

 

I'd also say Plugs (pull codes to look through the history)

But if plugs don't work I would look at Trans Fluid and filter

Recently when my trans fluid was getting due for replacement, at low speeds the car would shudder and it felt like I was bouncing very slightly in my seat

 

changed plugs, still has shudder. Thinking it is Trans related. No codes at all.

I am going to pickup a up some fluid and a filter... you guys think I should go ahead and do the conductor plate, since I will have the pan off?

 

Glycol contamination? I can't remember exactly the cutoff but I think it was in 2004.

 

Definetly 2004, if not even earlier? I had something like 9/2003 in mind?

 

Mine was built 11/2003 and I believe 9/2003 was the cut off.

 

is your fluid level correct? What does "smooth engine running" look like in DAS? Doing the conductor plate wouldn't hurt anything however the price is up to you if you want to pay for one.


unless you catch the fluid coming out, you'll need a dipstick to check fluid level too btw....

 

Still new with using DAS for monitoring things, so far have only used it for changing settings. When I get home next week I will do some more indepth DAS diagnostics. I do happen to have a dipstick that I bought and used with my C55. have to locate the service tube, is it in the same place as C55, back of engine on passenger side?

 

Sure is. if in fact you have a .6 trans.

 

Toque converter.

I just went through this with my e500. Low rpm (1500-2500) shudder. No codes were showing. I replaced plugs, wires, changed out TB, fuel pumps and still did it. After the TC change runs great.

 

You sure you don't have glycol contamination from your radiator? Maybe you just replaced the torque converter and it will only be OK until the new fluid gets contaminated again. Was this checked?

 

yes it was tested and it's clean.

 

Yup, when tc is finished it will do this.

 

If/when you decide to change the tc, do the rear main seal and cps while you're there.

 

I had same problem. I did fuel pump with sending unit, plugs, wire etc. And it was my damn TRANSMISSION MOUNT. I'm gonna ha to say it's the transmission mount.

 

doing Trans mount next weekend. but I am leaning heavily toward Torque Converter. DAS shows no codes for anything. I haven't tried disabling the TC clutch to see what difference that makes, though.

 

Ok so decided to have a look at my radiator, and sure enough it is a Valeo (it has the teeth style crimp not the wavy crimp) I have been told that even if it is a Valeo, base on the build date of my car I should be fine, but I am going to go ahead and check for glycol contamination. Does anyone know where I can purchase those glycol test strips that show how much contamination is present?

 

Should find out tomorrow. Dropped off at Lokey in Clearwater to do an alignment, check for glycol contamination, and to check evap system (randomly get smal leak detected since fuel tank replaced).
Replaced control arms, thrust arms and upper ball joints, reason for alignment. Driving a 2016 E350 loaner for a few days.

 

So dealer charged $140 for glycol test, which was a Hugh rip off. But it came out 0% glycol in transmission. So going to flush and change filter. Then if still an issue looks like my next step would be torque converter

 

Whatever happened here? Did you get the issue fixed?