Shaking only in drive and slight surge vibration braking

GENESIS88

MEMBER
2003 MERCEDES BENZ E320
3.2L
V6
2WD
AUTOMATIC
127,500 MILES

Car started to shake in drive only in idle. It doesn't happen in neutral reverse or park. Also, when braking almost at a full stop it will surge slightly, shake then continue to shake in drive. This issue is intermittent. Sometimes you can shut car off and turn back on and it goes away. I can give It gas redline 1 gear and it goes away for a little or reduces amount of vibration. There are times where it will be dead still for day or two then happen again. It's a weird issue. The doesn't vibrate at all in park, reverse or neutral. No check engine light. Bank 1 fuel trim long and short is under +1.9 to +5.1 bank 2 is +3.9 to +6.2 sometimes both banks are 0 to 1.9 combined all 4. Mass air flow is 7gram in idle. Tps 1.2 to 1.6% Idle. Note I took off air box and reinstall and went away but comes back. Smoke testing showed no leaks. Coils, wires and plugs are new. Graphed tps when driving and no dead spots. Only thing I found is bank 2 ltft is high compared to bank 1. I'm at a lost what I can be. Hoping someone can help me out.

8 Replies

GENESIS88

MEMBER
140 POSTS

Just a side note. When car is on but not running if I press gas pedal all the way down and activate kick down switch. Then turn car on it throws a code p0123 (pedal position sensor) low voltage OEM enhanced codes. If you do something while driving it doesn't throw code. No mil light on just code. MAF sensor should read around 4.5 to 5 grams a second. Most part it read that but few times it reads 3.6 to 4.2 grams second/.49 lbs to.58 lbs minute. So slightly under reading. It doesn't read 7 grams that was typo.

SPONSORED LINKS

Was this

answer

helpful?

Yes

Monday, November 1st, 2021 AT 10:40 AM

KASEKENNY

MECHANIC
18,907 POSTS

I suspect you have a torque converter issue. If you have a scan tool that can monitor this data, can you monitor the RPM vs the input speed sensor? Basically, you should see the input and RPM be pretty much the same, but I suspect in first gear they will be different which means the converter is not transferring the power properly.

https://www.2carpros.com/articles/engine-surges

Also, I am attaching a TSB that has a similar complaint and it talks about a converter issue as well. However, this is not going to solve your issue. This is talking about how to break in a new torque converter to stop this issue from happening. I am attaching this because it displays how the torque converter can cause these types of issues.

Basically, we can eliminate an engine issue if when this issue starts, you bump it to N and the issue stops. That tells us that we most likely have an issue in the transmission and the likely cause is the converter.

Let me know what you find with this or what questions you have. Thanks

Image (Click to make bigger)

Was this

answer

helpful?

Yes

Monday, November 1st, 2021 AT 3:11 PM

GENESIS88

MEMBER
140 POSTS

Highly doubt it's the torque converter. It works perfectly when driving. It kicks on and off just to Ike it should and when engaged there is no surging or slippage. A torque converter isn't going to give me issues in drive only when idling then Work perfectly the rest of the time. . Simplest way to describe, it feels like blown motor mounts but only in drive at idle.

Was this

answer

helpful?

Yes

Monday, November 1st, 2021 AT 5:53 PM

KASEKENNY

MECHANIC
18,907 POSTS

You are describing the operation of the torque converter clutch and not the torque converter. However, if you are sure, it is not the converter, then have you checked the mounts if that is what it feels like? Have you checked for a vacuum leak?

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

The o2 sensors are showing slightly lean so there is a chance that this is a lean misfire. However, what are the o2 sensors doing when this vibration is not there? Are they the same because if they are then that is not the issue?

You said that they go to 0 at times, when are these times that they go to 0? They should be switching around 0 but if they are steadily positive then that could be an issue.

Again, this would not make sense to be in drive only.

Have you checked the transmission fluid? If this is only in drive at idle (first gear) then that is going to be a different torque load through the converter then in reverse. Also, the fact that this is surging slightly when slowing down, that points to this as well.

I get that you are convinced that this is not the issue but I have seen this exact issue on different vehicles, so it is worth checking. You just need to monitor the RPM vs the turbine speed when it is vibrating and see if they are off.

Otherwise, let us know about the o2 sensors when this is not shaking and see if they are different.

Images (Click to make bigger)

Was this

answer

helpful?

Yes

Monday, November 1st, 2021 AT 7:36 PM

GENESIS88

MEMBER
140 POSTS

Hooked up car to a lot better scanner. Issues was found. Looking through live data came across misfire rates. Coil 3 and coil 5 are the issue. Both were causing random misfire with coil 5 being the worst. Weird enough second car goes into drive the misfire rate jumps. Had spare coil packs, replaced no more miss and car almost stopped shaking. Then my Friend looked at live data when I was driving. He noticed slight drop off in voltage with MAF that happens suddenly and correctly immediately. My scanner wasn't able to pick it up. Buddy had a spare MAF and now all vibration is gone. Funny I just replaced coils plugs and wires 200 miles ago. Just for fun we put the coils and MAF in his car which is same as mine. It did the same exact thing so that rules out wiring or computer issues. So, it was definitely the 2 coil packs and MAF.

SPONSORED LINKS

Was this

answer

helpful?

Yes

Tuesday, November 2nd, 2021 AT 2:24 AM

KASEKENNY

MECHANIC
18,907 POSTS

Wow. Great find. So, it was in fact a lean misfire. That is great info as the short-term fuel trims were showing this but normally the little but that they were positive doesn’t cause an issue but clearly on this engine combination it does.

Thanks for confirming that for us.

Was this

answer

helpful?

Yes

Tuesday, November 2nd, 2021 AT 5:13 AM

GENESIS88

MEMBER
140 POSTS

Mercedes are weird cars. My reverse light burned out and my car went into limp mode couldn't drive till I replaced it. Another issue my friend car kept pulling o2 sensor codes car ran crappy with car +20 fuel trims. Car gone into limp mode few times. Also, the car had shifting problems. He replaced the bank 1 sensor 1. Didn't fix anything. Mercedes said it's a bad cat. Mercedes Specialist said it's vacuum leak and exhaust leak plus bad fuel filter. I looked over his car and noticed the downstream oxygen sensor was lazy but working. I replaced it for him reset car and doom it worked. Everyone said I was crazy cause downstream don't do anything but read Exhaust after cat. We talked to both places he took his car and the shops said there amazed that was the issue. But in retrospect it makes perfect sense. B1s2 sends false data to computer. Computer see that and starts adjusting trims even though trims are good. Since that reading isn't matching up. Computer sees the issue and alters data based off false reading on sensor 2 altering sensor 1. Afterwards one of the Mercedes guy said we had dozens of cars come in throughout the years with bank1 o2 sensor codes that we can never figure out. We thought bad wires, sensor computer ECT. Never would of guess and another o2.

Was this

answer

helpful?

Yes

Tuesday, November 2nd, 2021 AT 7:49 AM

KASEKENNY

MECHANIC
18,907 POSTS

That's crazy but it normally always makes sense after the fact. I am more of a domestic expert but can get by on these import vehicles but have seen enough to know they are odd.

Thanks for that info as well. Please let us know how we can help in the future.

Was this

answer

helpful?

Yes

Tuesday, November 2nd, 2021 AT 10:25 AM