Car smoking at idle?? - Page 2 - PeachParts Mercedes-Benz Forum

siral3x · #16 03-11-2008, 08:51 PM

Quote:

Originally Posted by pawoSD

The fuel will spray from where the return line attaches because the injection pump itself also returns some fuel to that assembly and its easier for it to push out the open hole right there than it is to push it back to the tank...when you cover it with your finger it will go to the tank as usual. If your primer pump area is leaky/wet than it is leaking and potentially introducing air to the system. I'd replace it, its pretty easy to change out and its cheap. Also, the rubber lines between the hard line from the tank to the pre-filter and from pre-filter to primer pump need to be in good shape, sometimes the ends can deteriorate, this can also introduce air or allow a leak.

Siral3x, where are you located in MI? I am in MI too. Nice to see another MI dieseler! My car (actually all three of ours) smoke a bit at cold start too, its normal. Two even have the afterglow system and still smoke. After a few mins it clears up though.

There is somewhat a little air in the pre-filter. What's an easy way to vent the pre-filter??

babymog · #17 03-11-2008, 10:05 PM

It's normal to have air in the pre-filter, won't make any difference provided it's below the outlet tube.

siral3x · #18 03-11-2008, 10:32 PM

Quote:

Originally Posted by babymog

It's normal to have air in the pre-filter, won't make any difference provided it's below the outlet tube.

Yep, it's not at the outlet tube...but I would try anything at this point to fix the issue.
The one thing I wanna do is feed the engine from a test bottle...that way I would find out if my fuel lines/tank are crappy, however I'm skeptical since the Benz is my daily driver and I can't have it down whatsoever.
I'm doing a cold start in 30 min or so and repost....

siral3x · #19 03-11-2008, 11:30 PM

Ok, just did a cold start and a 6 mile trip.
Engine fired right up and for the first time I didn't had to rev it and keep it at 1k to keep it idle. It did not died and the motor was missing wayyy less after I replaced the injector return lines.
I got out of the car right away and I again blocked the nipple on the fuel filter housing, and VOILA NO MORE MISS/STUMBLE at ALL with a bone cold engine. My car seemed to run smoother and quieter then ever!!!
I have no explanation on what's going on!!!!??????
I plugged the inj no 1 return line back in and it started to miss again, and as the coolant reached 80C it stoped on it's own.
I could not belive that the start up smoke was almost inexistent, and went away in no time.
I get to my destination, shut of the engine for 5 min and let it sit, glow and crank back again, engine fires right up and misses for 10 sec then goes away.
Bottom line is that I have no idea how to fix the miss/stumble unless I block of that return nipple!! NO GOOD! However even changing the inj return lines helped a LOT, but did not completely fixed my problem..

I have only 1 theory behind this:
When I bought the car the return "cigar hose" from main fuel filter to metal line was leaking and I changed it with a smaller diameter fuel hose.
Could it be possible that the new hose is not big enough for the returned amout of fuel or maybe I have a clogged return metal line not letting enough fuel go thru causing my poor idle/missing????
What else could it be????

rrgrassi · #20 03-12-2008, 12:10 AM

The Cigar hose just dampens the pulse of the fuel returing to the tank. People have just used regular fuel line instead of a cigar hose.

That said, the pulse not being dampened could have a negative effect, and by you plugging the return from the #i injector reduces the amount of fuel going through the return. I wonder if there is some residual air in the system.

When you manually move the fuel linkage, does the air bubble in the primary filter get much bigger or just a little? If it gets much bigger, air is still getting into your fuel system.

pawoSD · #21 03-12-2008, 12:18 AM

After sitting 8 years that car sounds like it needs a good italian tuneup, have you tried really working it on the highway and such?. You did replace the fuel filters and such right away right? And yes a bubble in the pre-filter is normal. I'd replace those rubber lines if they are weeping though.

I go to Ludington quite often during the warmer months, its a beautiful place. I could stop by and say hello sometime!

siral3x · #22 03-12-2008, 10:10 AM

Quote:

Originally Posted by pawoSD

After sitting 8 years that car sounds like it needs a good italian tuneup, have you tried really working it on the highway and such?. You did replace the fuel filters and such right away right? And yes a bubble in the pre-filter is normal. I'd replace those rubber lines if they are weeping though.

I go to Ludington quite often during the warmer months, its a beautiful place. I could stop by and say hello sometime!

Yes, the fuel filters have been changed. I drove the car a lot on the freeway. I'm going to change the primer pump as soon as I get it. All other fuel lines have been changed in the engine bay compartment.
I live 2 blocks from the lake...I work at the local RadioShack...so stop by when you can!

siral3x · #23 03-12-2008, 08:37 PM

I want to replaced the lines from the primer pump to main filter. My line is transparent.
What kind of fuel hose should I use as a replacement?

pawoSD · #24 03-13-2008, 12:18 AM

Quote:

Originally Posted by siral3x

I want to replaced the lines from the primer pump to main filter. My line is transparent.
What kind of fuel hose should I use as a replacement?

I think the best bet is to get the clear line from the dealer....or you could call phil from fast lane and see if he could get you some (very likely). His number is under the "buy parts" link at the top of the page.

By using the OEM stuff you know it will work and won't have issues.

When attaching it its best to stick the end of the line in hot water for a min or two to soften the plastic a bit so it slides over the barbed fittings ok.

Next time I am in Ludington I'll be sure to stop by!

siral3x · #25 03-13-2008, 11:07 PM

Quote:

Originally Posted by pawoSD

I think the best bet is to get the clear line from the dealer....or you could call phil from fast lane and see if he could get you some (very likely). His number is under the "buy parts" link at the top of the page.

By using the OEM stuff you know it will work and won't have issues.

When attaching it its best to stick the end of the line in hot water for a min or two to soften the plastic a bit so it slides over the barbed fittings ok.

Next time I am in Ludington I'll be sure to stop by!

I decided I would try to get some air out using the priming pump, and as soon as I pumped it once fuel started gushing out like crazy around the handle. I screwed the knob back in and parked the Benz for the weekend till I get a new priming pump. Back to driving my Eclipse now...

siral3x · #26 03-16-2008, 11:18 AM

I have changed the priming pump yesterday, and bled all the air out.
The car still blows clouds of smoke and idles ****ty. It clears out when the engine hits 80C.
My friend that has been around diesels more then I have said that my injectors nozzles must be really worn, and that I need a new air filter.
I have been putting the injectors on the backburner bc I was going to purchase some Bosh nozzles from Europe this summer, but I can't wait anymore.
What do you guys recommed for nozzles??? Where do you guys source them???

siral3x · #27 03-25-2008, 01:49 PM

UPDATE:

-swapped out the injectors with a rebuilt pair;
-swapped out the old Autolite GP with O.E.M Bosch;
-new primer pump, all fuel hoses are new;
-new air filter;
-turbo shaft spins free;
-fuel gets to all injectors, IP seems fine;

I have tried everything I can think of and NO LUCK:
-car misses at idle and blows clouds of dark blue smoke (unburnt fuel);
-does not burn oil nor coolant;

It used to quit the stumble/miss once the engine warmed up to 80C, BUT now it's getting worse and worse! It starts up fine every time and has this horrid miss/stumble.
The car is due for a valve adj again, but I'm waiting on the valve cover gasket at the moment before I do it.
Would a valve adj. fix my stumble/miss/excessive smoke or am I wasting my days off again?? I'm on the verge of giving up on this car. It's sad that I had only problems with it. I don't remember having any problems with my old 240D except minor stuff/regular maintainace.

werminghausen · #28 03-25-2008, 05:52 PM

Quote:

Originally Posted by siral3x

I have changed the priming pump yesterday, and bled all the air out.
The car still blows clouds of smoke and idles ****ty. It clears out when the engine hits 80C.
My friend that has been around diesels more then I have said that my injectors nozzles must be really worn, and that I need a new air filter.
I have been putting the injectors on the backburner bc I was going to purchase some Bosh nozzles from Europe this summer, but I can't wait anymore.
What do you guys recommed for nozzles??? Where do you guys source them???

Consider Monark Diesel nozzles made in Germany- Sean Watts is selling them, about $20. I can balance them for you if you need. Martin

Mustang_man298 · #29 03-25-2008, 09:53 PM

Have you run a compression test on it yet, checked the IP timing, & checked timing chain stretch?

I would get that valve adjust done soon, especially if you have a low compression reading. These valves tighten up on the rockers as they wear, and if there's one not quite seating anymore it will burn the valve.

siral3x · #30 03-25-2008, 10:50 PM

Quote:

Originally Posted by Mustang_man298

Have you run a compression test on it yet, checked the IP timing, & checked timing chain stretch?

I would get that valve adjust done soon, especially if you have a low compression reading. These valves tighten up on the rockers as they wear, and if there's one not quite seating anymore it will burn the valve.

Why would the valve burn?? I was thinking that if the valves tighten up then compression would leak out of the combustion chamber.