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  #1  
Old 11-05-2002, 03:36 PM
John_Schwarz
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Rough Starts for E420; Injectors Cleaned, etc., - now what???

When first starting the car in the morning, it feels like somebody is doing jumping-jacks on the front of car. This lasts for around 30 to 60 seconds.

When starting the car after it has been sitting for awhile it is not a smooth start (not nearly as bad as the firsm morning start, but still not good). It kicks over, feels like a big miss and then kicks over again.

The injectors were removed, cleaned and had the following items replaced - pintle caps, filter baskets, o-ring seal top & bottom. Before having the injectors removed, the jumping-jack problem was once every couple of weeks and there was no problem with restarts.

Also, the wiring harness has been replaced. Additives have been tried (Techron, Heat (for removing water) & octane booster). No difference.

Needless to say, the car is headed back to the shop. Assuming the injectors check out okay - what else could the problem be???

Thanks,
John

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  #2  
Old 11-05-2002, 03:40 PM
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I wonder if this problem is related to your engine missing at idle and steering wheel vibration?
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2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #3  
Old 11-05-2002, 04:47 PM
John_Schwarz
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I'm guessing there's a possible vacuum leak causing the idling vibration & the fuel pressure regulator or accumulator for the morning starts. But these are just guesses. With fuel injectors going through a minor rebuild; I doubt it is a leaky fuel injector.

After reading 100s of posts, I did notice one of your posts said if the air mass sensor failed (or is failing???) then the idle could oscillate. The idle is oscillating but not enough to notice on the tach, but you can hear it alittle. While giving the car alittle gas (foot on brake and car in gear), the oscillation is easier to hear. While doing thing, I'm giving the car just enough gas to to raise the oscillation noise/vibration - but the tach is still pretty much at the same 500 RPMs. Can air mass filter gradually decay in performance, or is dichotomous - when they fail it is all at once?

One thing i did notice, the RPMs don't change whether the car has the AC on or off. Is this normal (I expected the RPMs to be alittle higher with the AC on).

While in drive, if you give the car just alittle more gas (the RPMs barely go up - if at all) then the vibration goes away. What influence the '95 420's idle speed? While driving, the car feels normal. So, it sounds logical to me that it something control the idle speed, or something providing an input to the idle speed.

I'm going crazy with this (alittle broke too!).

Thanks, John.
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  #4  
Old 11-05-2002, 05:59 PM
John_Schwarz
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I listened to the car for awhile and noticed a whining sound coming from the rear of car. It was very faint and sounded like a real slow squeak (not high in pitch) - kind of like somebody cleaning a glass window.

I thought it might be pressure escaping from the gas cap, so I opened it and released the pressure. Got back into the car and could still hear it. You can't hear it from the outside of the car; there's too much engine and exhaust noise.

Whether the car was in park or drive, you can still hear and the frequency didn't seem to change. I tried revving the engine in park, but cabin noise increases and you can't hear the squeak any more - I want to see how it changed with acceleration.

Anyway, I'm guessing this is the fuel pump crying, "Replace me!"...
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  #5  
Old 11-05-2002, 06:03 PM
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Sounds exactly like the fuel pump.

You actually have two of them.

I'm wondering if this is the source of all your problems...
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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #6  
Old 11-05-2002, 07:15 PM
ILUVMILS's Avatar
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You need to check the fuel system pressure before replacing anything. From what you've described it sounds like the system isn't holding pressure when not running. This would cause long cranking and/or rough running following start-up because the pump(s) need to build up lost pressure before the engine can start and run smoothly. I honestly haven't seen too many happy endings after using fuel additives. A worn injector that's leaking down over night or a fuel pump check valve that's leaking internally needs to be replaced. Simply connect a fuel pressure guage and verify the correct pressure(s) with the engine running. If everything is OK shut it off and monitor the pressure(overnight if necessary) to see if it drops below spec. From your description I think you'll see a pressure loss within an hour or two if, indeed it's fuel-related. Also, don't overlook the ignition suppressors. They're easy to test and cheap to replace. If it's an LH-SFI 119 engine have a look at the caps and rotors too. I've tossed hundreds of them in the trash over the years. A little bit of green stuff inside the cap is all it takes to cause a running problem. Good luck
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  #7  
Old 11-05-2002, 08:02 PM
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I had lots of problems with sluggish morning starts. Same symptoms that you describe.

I had my valve seals changed and the problem went away.
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  #8  
Old 11-05-2002, 09:18 PM
John_Schwarz
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ILUVMILS-

The car is going back in tomorrow night so they can do a fuel pressure check overnight. We're going alittle crazy with this problem trying to figure out if the idle and starting problems are part of the same issue or two seperate issues. Since neither is getting resolved, it feels like we're going in circles.

AuctorEcclesiae-

The car isn't sluggish at all; just the king of mis-fires in the morning. After 30 seconds or so, it settles down. While it misfiring, the car will rev just fine - just with a whole lot of shaking.

suginami-

Oh great - two parts they can replace While not excited to spend $200 per pump, I would like to see the car just completely fail one of the tests. However, I'm still not optimistic. How do the fuel sending unit, fuel pressure regulator and/or accumulator figure into the "rough start" problem?
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  #9  
Old 11-05-2002, 09:24 PM
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John, I felt the same way you do now when my car was experiencing several different driveability problems. The diagnosis was apparently difficult for the technician to make, and was replacing a lot of parts that didn't seem to fix the problem completely. The car was getting better in small increments, but not completely. When the technician was testing parts, I was just hoping that something would be diagnosed as bad, just so that I would have a resolution.

I threw a ton of parts at the car to fix it. More than what you have so far.

If you'd like to read my saga and have time to kill, get a hanky first to wipe the tears from your eyes.

Do a search on all the posts I've made, and go to the very first posts I've made.

I've spent a fortune on this car. More than I'd ever imagine. But at least I won the battle, and the car really does run beautifully.
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2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #10  
Old 11-05-2002, 09:43 PM
John_Schwarz
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suginami -- I've read most of your posts and have been taking alot of notes! In the last 18 months, the car has set me back over $8k in maintenance and repairs. Add onto that another $3.5k for a repaint, $3k for a stereo and about another $1.5k in fun stuff. Hmmm - $22k for the car plus another $16k -- A monthly run rate of $1,700! What's the word I'm searching for --- "oooops"? I'm in so deep in this car, I would rather tell my fiancee that I cheated on her than admit how much this car has cost!

But yes, the dream (that tiny, tiny speck of light at the end of tunnel) is that the car will be back to where it should be and then it will go another 30k to 50k miles without issue. At 95k is has plenty of life left in it. On flip side, I took a tour through Parts Lane and totalled up all the major components between the fuel pumps to the engine and then a couple other sensors. This could easily go another $2k to $3k. The hard part is figuring out when just to give up.
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  #11  
Old 11-05-2002, 10:27 PM
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The amount of money I've spent is about what you've spent in the 16 months I have owned my car.

I haven't broken apart the really necessary maintenance and repair expenses from the "unnecessary" expenses (new wheels, shift knob, steering wheel, euro headlights, window tint, high-end audio equipment, bumper respray, etc.).

The two categories of expenses total almost $12,500!!!

I only paid $9,500 for the car, so it was a steal.

But, I have to tell you, at the end of the day, the car is so clean and immaculate it takes your breath away. It not only looks like a brand new car, it runs flawlessly.

And I love it. I can't imagine driving anything else.
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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #12  
Old 11-06-2002, 08:17 PM
John_Schwarz
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The car was dropped at the shop earlier this evening. From a cold start yesterday, the idle reach an all-time worse - AFTER the injectors were rebuilt & wiring harness replaced.

As for the fuel pump noise mentioned earlier, it hasn't happened again. Oh well... The short term plan is a fuel pressure test; I'm guessing the fuel pressure accumulator or something along those lines is amiss. Also, looking at the 90k service invoice, they didn't change the fuel filter. So that's on the list of things to be replaced.

On the plus side, got a new Cooper S as the loaner. Nifty car with navigation system - but the overheat light came on/off after a turn - I'm guessing the fluid level is low. Pretty tight car, but the acceleration isn't what I expected - zero torque. Reminds me of the Honda S2000 - keeping the rev's at 4k and above = fun car. Otherwise it's a dog.
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  #13  
Old 11-06-2002, 08:31 PM
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Hi John:

I should have been clearer in my last post RE: valve seals. The car shook something awful; it stuttered a bit, and then smoothed out and purred like a kitten after. After the seals where changed out, that went away.

Sorry for not being so specific.
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  #14  
Old 11-06-2002, 08:38 PM
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The M103 engines are very notorious for valve seal problems.

M104 and M117 engines have virtually no problems with wearing out valve seals, except I suppose at extremely high mileage, and his car is just broken in.

If he had worn out valve seals, he'd likely find oil on his spark plugs, and be consuming oil internally.

I don't think valve seals are his problem.
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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".
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  #15  
Old 11-07-2002, 12:07 AM
John_Schwarz
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My guess is either fuel delivery or vacuum.

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