1997 e420 Headache
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1997 Mercedes E420
1997 e420 Headache
Hi all. I'm Gary and I'm new to the Mercedes Club. This is only my second Mercedes first was a 80 model 280d I loved that car. Well let me start car is in limp mode. Read through a lot and seen my harness was bad. I replaced the harness and ETA. Also swapped the K-40 relay for a brand new one at a cost of $161.00. Also replaced the MAF( with a cheap China knockoff from EBay) waste of money. Gonna buy the Bosch one this week. After I replaced everything and disconnected negative cable for about 30 minutes Asr and check engine lights are off car runs great but transmission still in limp mode. Also noticed after shutting the engine off and cranking back up check engine light came back on and car won't rev over 3000 rpm. But after resetting again I can nail it no problem. Sounds like the cheap Maf? I lost my job recently and was found intelligible to receive unemployment benefits ( which I am fighting in court) so money is extremely tight. I mean tight. This is the only car I have. I can't get anywhere hard to find a job without having your own transportation. I need help bad guys. Any advice would be greatly appreciated. Thank you all and God bless you.
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1997 Mercedes E420
Hi and thanks for the advice. I have took my car to the best Indy in my city. He had my car for two days. And afterwards told me to come pick it up didn't even charge me. Said he never seen anything like it. Said he cleared faults and they would come right back. So I don't know what to do. I can't afford the dealership. Not at the moment so I'm kind of stuck between a rock and hard place ya know.
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1997 Mercedes E420
Yeah I know right. Lmao. Well I think the new eta and wiring harness cleared a lot of the codes. No check engine light anymore. Dash no longer looks like a Christmas tree. I'm about to go out and check my fluid for level and condition of fluid. I made me a dipstick last night. I do not know if the Indy checked it or not didn't say. So first off I'm thinking of doing a filter and fluid change to see what happens. Depends on if I have old fluid inside that's dark. It could be possible they guy I bought it from may have not changed it in forever. Wish me luck. I have seen others posts with all sorts of people chiming in. Thank you much Plutoe. For your responses and advice. You are greatly appreciated.
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1997 Mercedes E420
Ok. Update I got codes pulled. I have po753. Po743, po758 and I think po763. I know they are torque converter electrical circuit and solenoids a,b,c electrical. Anyone know where I should proceed next? Any help would be greatly appreciated thank you.
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1997 Mercedes E420
Ok thanks for the heads up Plutoe. I have a friend that has a Snap on Modis. He came by long enough just to pull my codes with it. He was in a hurry so that's as far as I got. I have never seen solenoids. Are they expensive? Well I know they probably are. But could it possibly solve my issue if I replace the plate and the solenoids?
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1997 Mercedes E420
Ok I have encountered a new problem. I got a new battery. My other was fine just got a original Bosch for 50 bucks so could not pass it up. I was putting it in my car. I noticed upon hooking it up I'm getting way more sparks than normal it will smoke a little to. Like I'm getting a draw from something. Like a bad ground maybe? Could this be my original problem and the computer is putting into limp mode because of this issue?
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1997 Mercedes E420
On another note I was going through my cars work history. And I noticed the instrument cluster was replaced any not long ago. Could it maybe have went bad again? And could a bad cluster cause any of the problems I am having. Just looking for any and all avenues of where to proceed. Thank you. And a big thank you to Plutoe. God bless you man.
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1997 Mercedes E420
Ha ha. One question if my car was in electronic limp mode and it cuts power to the transmission through the TCM. Ok it's 6 solenoids on the conductor plate. I only have fault codes for 4. If I was in electronic limp mode wouldn't their be faults for all 6 solenoids since their would be no power there presumably? Any answers are appreciated thanks.
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1997 Mercedes E420
You must hate God. You were very helpful at first. But since I said God bless you. You have been nothing but an *******. Hey I'm sorry if you don't like God. I was just thanking you for your help. And not for you to be a smart ***. If you we're in front of me right now. You would be Plutoe for real because I would kick your *** all the way up there to it. Believe that.
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I would also look at obvious things, including the wiring that goes from the transmission to the transmission computer. The harness that enters the transmission is notorious for having fluid leak past the seals. This fluid then actually travels up the cabling and fills the transmission ECU with fluid which causes all sorts of issues.
You can check this yourself by opening the module box (which is where you found relay K40), and looking at the first module from the bottom - it should have two big multipole connectors with cables routed to the left and right. Remove the two connectors and check for oil or fluid contamination here. If it's perfectly dry, you're good to go. If there are signs of wetness, or oil, remove the module and check for fluid contamination. I saw one that held about 1 pint of fluid that drained away when we removed it. After cleaning with 99% alcohol and electronics cleaner it worked fine.
This is something that represents a common issue on W210 vehicles, that can be easily checked without scanning for codes, and does not involve buying parts. It's uncommon (but not unheard of) for 4 solenoids to become defective at the same time. That being said, replacing the solenoids, while possible, will inevitably require use of a Mercedes (or equivalent) scan tool to properly do the adaptations.
You can check this yourself by opening the module box (which is where you found relay K40), and looking at the first module from the bottom - it should have two big multipole connectors with cables routed to the left and right. Remove the two connectors and check for oil or fluid contamination here. If it's perfectly dry, you're good to go. If there are signs of wetness, or oil, remove the module and check for fluid contamination. I saw one that held about 1 pint of fluid that drained away when we removed it. After cleaning with 99% alcohol and electronics cleaner it worked fine.
This is something that represents a common issue on W210 vehicles, that can be easily checked without scanning for codes, and does not involve buying parts. It's uncommon (but not unheard of) for 4 solenoids to become defective at the same time. That being said, replacing the solenoids, while possible, will inevitably require use of a Mercedes (or equivalent) scan tool to properly do the adaptations.
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1997 Mercedes E420
Hey thanks for your response. I have checked the transmission module it's perfectly dry no bad connection. I also took the plug out of the transmission. It was dry no leakage at all. And could it be maybe the copper ribbon on the plate broke and is not powering those certain solenoids? I have heard that plate is very prone to failure that's why they updated it right? But I have no leaking wires look good no fluid leaks. I'm thinking about draining it and have a look at that plate and take the solenoids to my transmission guy and have him test them for power and open and closing. Won't hurt
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1997 Mercedes E420
I just looked at my vacuum lines. I just found a leak going to my EGR valve. Could this cause any of my issues? Just asking. I'm very mechanically inclined. Worked on cars ally life. Just a newbie to the Mercedes brand. Any suggestions?
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There is alot of "could happen". Keep in mind that once you drain the transmission you will have to refill it with fresh fluid which is costly, and a new seal which isn't expensive but still one that you will have to pay for. If your transmission does not have a dipstick (some early 5 speeds still did), you will have to obtain the service dipstick tool, and then it is still difficult because you must use a scan tool to determine the fluid temperature as the level can only be properly checked at a certain temperature.
My advice, which probably is not what you want to hear, is to take it to your "transmission guy" and have him put a full estimate together. If you can't afford it, at least get the diagnosis information from him, if the estimate was not free.
My advice, which probably is not what you want to hear, is to take it to your "transmission guy" and have him put a full estimate together. If you can't afford it, at least get the diagnosis information from him, if the estimate was not free.
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1997 Mercedes E420
I just called my transmission guy. They do not charge for diagnosis. So I have heard that the better shops have the ability to actually pull the codes from the ecu so they can really look at the transmission. Is this correct. I am assuming they do since they do rebuilds and all. So at the least I will know what is going on thanks for that advice APL175. He told me to bring it and drop it off tomorrow. So I will know if I really have the conductor plate issue or whatever is going on. I am more than able to do the work myself. I used my sons infrared thermometer to scan the pan for temperature. It works like a charm. Wish me luck. Thanks guys
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1997 Mercedes E420
I'm getting ever so close to solving my limp mode issue. Have replaced a lot of parts. New wire harness, new k40 relay. New eta, maf, brake light switch and crank position sensor. After I fix this thing I'm gonna do the wheel sensors just as a precaution. And a few other things. Can't wait to drive my baby again.
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99 E320
I just called my transmission guy. They do not charge for diagnosis. So I have heard that the better shops have the ability to actually pull the codes from the ecu so they can really look at the transmission. Is this correct. I am assuming they do since they do rebuilds and all. So at the least I will know what is going on thanks for that advice APL175. He told me to bring it and drop it off tomorrow. So I will know if I really have the conductor plate issue or whatever is going on. I am more than able to do the work myself. I used my sons infrared thermometer to scan the pan for temperature. It works like a charm. Wish me luck. Thanks guys
sophisticated equipment which features this capability. it's not an ODBII
reader but manuf specific modules. there are even asian clone/pirated units
out there which mimic the MB SDS equipment
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1997 Mercedes E420
I was looking into one. Think I'm gonna get one called a Launch Creader V11 I seem it on here and guys say it works well with Mercedes. I think I'm gonna get one and clear my ecu and tcm. And see if they come back before I go any further.
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E420
I have followed your conversations with some interest as I have had problems with the transmission, went away and has come back with a slight difference.
the first time round, I was spending money on the MB services' call. it started with gear disengagement, temperature running high and light saying check engine electronics. I manage to limp to the service station.
one el tonic plates after another, transmission oil changed at the same time, the bills came to 3000 and it was still coming out of gear with much anxiety driving in highway conditions.
a separate transmission "specialist" could not find the problem but suggested that running on high temperature could cause gear slippage. I discovered that the auxiliary slave fan did not run. after replacing the drive belt the fans kicked in and problem solved.
I wrote and demanded my money back and to MB's credit, I got a full refund.
one year one, the gear slipped but this time gear engagement comes with a clunk and a jerk and gear slips after a short drive. I am not taking the car to MB but to anAAA garage and will see what transpires. I wish I was more adventurous going under the car with grease elbows !
oh, my car has done 130000 miles.
the first time round, I was spending money on the MB services' call. it started with gear disengagement, temperature running high and light saying check engine electronics. I manage to limp to the service station.
one el tonic plates after another, transmission oil changed at the same time, the bills came to 3000 and it was still coming out of gear with much anxiety driving in highway conditions.
a separate transmission "specialist" could not find the problem but suggested that running on high temperature could cause gear slippage. I discovered that the auxiliary slave fan did not run. after replacing the drive belt the fans kicked in and problem solved.
I wrote and demanded my money back and to MB's credit, I got a full refund.
one year one, the gear slipped but this time gear engagement comes with a clunk and a jerk and gear slips after a short drive. I am not taking the car to MB but to anAAA garage and will see what transpires. I wish I was more adventurous going under the car with grease elbows !
oh, my car has done 130000 miles.
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1997 Mercedes E420
I'm still having problems myself. Trying to get in contact with a ECM repair guy that's real god and cheap. I'm starting to have suspicions I may have a bad ECM. Can't hurt he does not charge to inspect them. Mine does have a little corrosion on the connectors. But taking it to transmission guy tomorrow to see what he says. If he says the plate is bad I will change it myself. Just hoping and praying something works soon. Anybody been through this and have any thing different I have not tried yet. I'm taking any and all suggestions
