Injector Replacement - PeachParts Mercedes-Benz Forum

shoe · #1 09-23-2003, 03:15 PM

I am thinking of replacing the injectors in my 96 E300D. Other than removing the intake and the injectors what else can I expect to do, eg. copper washers reaming injector bores? After reading a few post on how quite other diesels of the same vintage and mileage readings (not to mention 275k+ miles) I believe it is time....... Opinions?

P.E.Haiges · #2 09-23-2003, 06:49 PM

Shoe,

If it ain't broke, don't fix it.

If you engine runs good without knocking or nailing and gets about the same mileage as before, you injectors are OK.

But if you need peace of mind, remove the injectors and take them to a Diesel injection shop to be tested. Then decide if you want to replace them or have new tips put in.

P E H

shoe · #3 09-23-2003, 07:43 PM

PEH,

I normally subscribe to that very theory, however the engine is a little noisey. I would not consider it "nailing" but noisier than I would have expected it to be (maybe I am over sensitive). Since I have only had the car for about three or four months I am not sure how loud the combustion of these cars is supposed to be. I never gave any thought to having just the tips replaced, my only hesitation to that is I really cannot do with out the car for an extended time period. But I will look into it. Thanks for the reply and insight.

Rick Miley · #4 09-24-2003, 09:30 AM

If you decide to go for new injectors, still have them tested before you put them in. The Mercedes-Benz dealer installed brand new injectors in my E300 at 40K miles. (Because they were too stupid to diagnose a failed glow plug) One of those new injectors nailed for weeks.

shoe · #5 09-24-2003, 04:52 PM

Rick,

How much engine noise can you hear on your 99 with the hood closed at idle?

Rick Miley · #6 09-25-2003, 08:59 AM

Boy, that's a really hard thing to answer. You can hear some noise, but it's definitely not loud. You can tell that it's a Diesel, but it's certainly nothing like a 616 or 617. So I guess I would say half way beteeen a 617 and a gasser, how's that?

The best thing I've found for noise reduction is biodiesel. On a 20% mix, from inside the car, you really would mistake the engine for a gasser - it is that smooth and quiet. The 240D really likes the stuff as well. It make some difference in the TDI, but not as much.

leathermang · #7 09-25-2003, 09:44 AM

OK,, Rick and Shoe.... I have figured this out...
Each of you go out to your cars with your cell phone... hold your phone in the engine compartment... alternately .... and put your finger over your other ear... and take it off.... several times... that way you can compare which is louder....

shoe · #8 09-25-2003, 11:10 AM

Ok, I think mine is somewhat louder than what your discribing, my nephew say's he can hear us coming down the street if he is out side. Leathermang you have a good idea

leathermang · #9 09-25-2003, 11:42 AM

I did read lately that new properly set injectors are louder than old ones... so this is one time when more noise is better...

#10 09-25-2003, 12:05 PM

Try Diesel purge first. Also use Bioguard.
The post of have them tested is spot on.
You could be just throwing money away and get worse than you have.
I think Leatherman has "Phone stock" and he want you to raise his share price.
Good Luck.
Charlie

lrg · #11 09-25-2003, 02:07 PM

A good diesel repair/injection shop should be able to remove and test your injectors in a couple of hours. I agree with PEH, unless the sound is getting worse or other symptoms develop, I'd just keep driving.

shoe · #12 09-25-2003, 05:30 PM

Thanks folks all great info. I will start with the low cost items first

I will also reevaluate the sound of the engine too I may be way over sensitive to it. Leatherman looks like your stock will stay the same. Rick never offered his phone number

Rick Miley · #13 09-25-2003, 08:23 PM

Being the kind and generous person that I am, I called him.

shoe - The car sounds fine. Don't mess with it.

shoe · #14 09-25-2003, 09:12 PM

Rick and all you guy's are the reason I value this board so much. Rick called and we compared engine noise, I am quite satisfied the mine is normal:p :p. Now if I could just get rid of the ever increasing CEL for the glow plug circuit.

any way that is another story. I will pull the intake off and check the GP wiring and look for the GP engine coolant sensor to ohm it out. Thanks for all the help. Leatherman your idea was a god one after all

michakaveli · #15 11-01-2004, 10:58 PM

My injectors are quite loud, knocky and they nail. It's funny after this last tank where I added some canola oil, on cold start upafter the glowplug light goes off and I turn over she starts up so nicely and without kncokcing, or nailing. As you start driving it and the knocking gets worse. Recently I've heard it nailing at highway speeds. Kinda freaked my out.

Anyway it's obvious that I need injector service but I've also noticed this additional tick noise from under the hood. Maybe I had it before but I couldn't tell you. The tick happens when you bring up the rpm's to about 1500 or so then quickly let off the throttle, as the rpm's drop quickly there is a single tick, kinda like a large relay engaging. Sometime you can hear it on the increase of RPM. Usually it's the same volume tick but it does very rarely to slightly quiter or 1/10 times to no tick on the rev down.

Does this sound like an injector(s)? Tried to listen to it with the hood open but it's tough to pin point. Doesn't sound like it's coming from the injection pump but somewhere on the driver's side of the engine. Mileage hasn't really changed but the smell is diesel exhaust is a lot more prominent and smoking may have increased....