the car is a 190e- which has done 115,000 miles.

today i noticed a jerking/misfire while accelerating .

so far i had a new rotor ,distributor cap and spark plugs.

the fuel pump is a bit noisy.

any more ideas on what i should check/replace?

I think you just answered your own question, but I could be wrong. If the fuel pump is noisy, you should think about replacing it first. Low fuel pressure can cause a lot of strange problems.

xp

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1985 190E 2.3L - a constant project.

I think you need a new set of sparkplug cable.
Alex

A failing fuel pump certainly caused a miss on acceleration in my 190E. You might want to check the fuel filter first. You should change this anyway if you change the pump.

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Cheers, Neil

thanks for the input.

the filter was changed about 10,000 miles ago.


would a failing fuel pump cause an intermittent, unpredictable misfire?.

will also look to replace spark plug leads soon as these are the original ones are far as i am aware.

What kind of plugs?

Haasman

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'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)

In my case, at idle, the engine was also intermittently misfiring, in addition to misfiring/jerking on accel.

New spark plug leads solved my issues.

If your car doesn't misfire at idle, it would seem more like a fuelling problem.

Cheers.

Definitely do the spark plug leads IMO, i'll bet my 999th post (this is it) that will solve your problems.

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190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg

thanks for the further input and ideas.

this is why i like this forum-your feedback is very useful.

haasman,

the spark plugs are of the BERU brand -14k-7duo (which is the equivalent of bosch-h7dco).

azhari,

no misfire at idle-hence the fuel pump is a possibility as it is noisy on an intermittent basis.alos the jerking is intermittent-none of it recently-

I'll go with those above who recommend spark plug wires. I had a similar misfire/jerking at low rpm's and idle and a new set of wires cleared it up. In my case, watching the engine around the spark plugs at night allowed me to see the occassional crossfire.

good luck.

andrew

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1992 190E 2.6L

i have done the darkness test to check the plug leads for arcing-could not confirm any sign of arcing.

but i am planning to change the leads as they are 115k miles old.

also planning to change the electric fuel pump,which is noisy at times and is also 115k miles old.

i finally changed the spark plug wires(leads) today.

so will check if jerking on acceleration stops.

hope this cures it.

if not, then the electric fuel pump will be next

good call. keep us posted.

andrew

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1992 190E 2.6L

My '91 190e 2.3 was doing the exact same thing. I replaced all the ignition components except the coil (because of cost $114)and that didn't help, then I finally replaced the coil last Sunday and it went away. It was sputtering and skipping pretty bad off the line and at idle before that, now there's no more.

positive feedback-

after changing the spark plug wires the jerking(hesitation) on acceleration has stopped.

i am also having the bosch fuel pump changed as it is excessively noisy at times.

thanks for the useful advice .