1995 E320..... Thanks for the help! (and a few questions) - PeachParts Mercedes-Benz Forum

JMaxwell · #1 06-22-2005, 10:41 AM

First off, what a great forum! You guys are awesome.

I purchased a 1995 E320 W124 M104 last week up near Chicago. It has 95k on it and is in spectacular condition. After driving my dad's 99 E430 and my mom's 98 CLK320, I fell in love with Mercedes, and I knew this would be a great car.

Anyway, I started to notice a rough idle a few days later, and then the check engine light came on. I got a code #7 from the diagnostic box, and after reading here about that problem, I figured I should change the spark plugs and the connectors on 2,4 & 6. I purchased the correct Bosch F8DC4 plugs and connectors, and was ready to put them in. I pulled out the old plugs, and they were AC Delco brand, and the gaps were in the .43-.46 range! I set my gaps for the new plugs at .31, installed the connectors and was ready to go.

My car now drives beautifully! No more rough idle, and the acceleration is so much better it's hard to believe. If it weren't for this forum, this problem could have cost me a ton of money. Thanks, everyone. However, I have a few more questions:

1) I can't get the diagnostic box to blink at me anymore, not even once, no matter how short or long I hold the button down, so I can't reset the CE light. It appears that the wiring harness has been changed, but the box was working when I got my #7 code off of it, so I'm not sure what the problem is.

2) When I turn on my headlights, the "check exterior lights" button comes on, but then goes off after about 2 minutes. I checked all the lights with my brother, and we didn't see any out. Anyone have this problem, too? Is it a loose bulb or just faulty electronics or what?

3) I'm interested in that DIY diagnostic LED tool for the other pins, but can't seem to find it in the archives. I'm probably using the wrong keywords, can someone link or tell me what its called? Thanks

4) I live in Iowa, any suggestions for summer/winter engine oil types from anyone in this type of climate?

Again, thanks for all the help, I bow down to the collective knowledge avalible on this board. Looking forward to 200k.

John

Arthur Dalton · #2 06-22-2005, 11:07 AM

http://members.aol.com/ajdalton7/ledtool.jpg

skiier3_9 · #3 06-22-2005, 11:59 AM

for your CEL LED you have to have the ignition in the "on" position (but you don't have to have the car running) With the key in the "on" position hold the buttton down for 3-4 sec to read the codes and 8-10 to reset the CEL.

BTW where in iowa do you live?
I use 5w30 winter and 10w30 summer here in MN and WI, some ppl prefer heavier weight during the summer like SAE30 or SAE40 as well as 0W30 and 0W40 synthetics. Everyone has their own opinion on what oil and what weight so its really up to you.

http://www.chris-longhurst.com/carbibles/index.html?menu.html&engineoil_bible.html

JMaxwell · #4 06-22-2005, 12:15 PM

Thanks, Arthur and Skiier

I live (summer) in Muscatine, southeast Iowa on the Mississippi, and go to Iowa State in Ames.

About the LED..... I have the key in the on position, and when i hold the button down, the LED turns on red, and nothing happens when i release, no matter for how long I hold the button.

JMaxwell · #5 06-22-2005, 12:50 PM

tkamiya:

Only ever seen it come on when I turn my headlights on and it turns off pretty reliably after ~2min.

John

skiier3_9 · #6 06-22-2005, 01:06 PM

Nothing should happen unless your check engine light is on. If it is, then you've got another issue, not sure where to go from there.

Kestas · #7 06-22-2005, 01:51 PM

Quote:

Originally Posted by skiier3_9

I use 5w30 winter and 10w30 summer here in MN and WI, some ppl prefer heavier weight during the summer like SAE30 or SAE40 as well as 0W30 and 0W40 synthetics. Everyone has their own opinion on what oil and what weight so its really up to you.[/url]

Ditto... I do the same thing here in MI... 5W-30 in the winter and 10W-30 in the summer.

Arthur Dalton · #8 06-22-2005, 01:51 PM

< >>

The ECU has to go through all self test before it resets . That can take many drive cycles . Until then , there will be no flash back from N59 module
[ led/sw]
The other pins are not emmissions related , so they will flash back an instant single flash, no codes stored after clearing..

JMaxwell · #9 06-24-2005, 12:02 PM

OK, everything seems to be working well, thanks for all the input

To follow up & conclude:

1) The CE light went out after changing the plugs\connecters, and after several (3 I think) driving cycles, the computer just blinks once at me, so I know my emissions system is fine

2) I took out all the exterior light bulbs and reseated them, and a couple did feel loose (or at least they came out eaiser than most), and now the "check exterior lights" light no longer comes on, so that problem is fixed

3) Thanks Authur for that diagram, I'll assemble it tonight

I hope this thread helped others with similar problems, and again, thanks for all the input

John