engine shakes - PeachParts Mercedes-Benz Forum

azatrum · #1 03-19-2004, 01:18 AM

Hello everyone.This is my 1st post on this site. Excuse me 4 bad english and wrong spellings. I have a problem with my 89 190E 2.6. I posted the problem on benz world, got some responses, tried those but didnt help, so i may get my answer on this forum. Anyways heres the problem, there is a shake in the engine when the car idles, Seems like a missfire and the oil pressure and the economy guage keeps goin up & down a little bit, also i can smell fuel from inside the car. On starting the car, it seems that the engine is struggling 2 bring the idle 2 normal. Stays like this for 2 to 3 seconds then comes to normal, but then starts shaking. It only happens when the engine is warm, when its cold with rpm's high, it runs ok or when i start driving it, engine performs perfectly ok. got it checked by a mercedes expert, he said the fuel distributor is running rich on 1 cylender, so he was gonna do the tunup and adjust the mixture, he asked $500 4 the job without any guarentee's, so i didn't go 4 it. But ended up paying him $120. Later i changed the plugs, wires, rotor, cap myself, but problem remained. Today i took it to another shop, he adjusted the mixture,which was lean according 2 him, its performing alot better now, shakes are alot less, but still there, i paid $155 this time. Gas smell is still there but very little now.He says its an old car, so little bit of rough idle is normal. But i think, problem is a problem. Someone on the benz world suggested that it could b the oxygen sensor. Now it seems iam running out of options with the work shops, seems no body can detect the actual problem, and iam sick of waisting money without getting it fixed. Any suggestios will b highly appreciated. Thanx in advance.

sbourg · #2 03-19-2004, 02:39 AM

If you smell gas, and there is no black smoke out the tailpipe, then find the leak. Could be the fuel distributor is leaky, and gas is pooling below the vane of the airflow meter. Could also be a leaky diaphram in the fuel pressure regulator, with gas venting out the safety tube to the PCV orifice.

Once that is fixed, reanalyse your symptoms, if still present.

Steve

azatrum · #3 03-19-2004, 05:34 AM

Thanx steve 4 the reply. So do u think that a leak can caus a missfire which results in a shake? It could b. But i think the 1st mechanic would've told me if there was a leak. Also is it possible that the smell is of the fuel which is running down the exaust unburnt b caus of the missfire? I will check into it anyways. Can u please give me an idea about the location of the fuel pressure regulator? Thanx again.

Meza · #4 03-19-2004, 07:40 PM

I am curious to find what's causing it..

sbourg · #5 03-21-2004, 08:30 AM

Quote:

Originally posted by azatrum
So do u think that a leak can caus a missfire which results in a shake? It could b. But i think the 1st mechanic would've told me if there was a leak. Also is it possible that the smell is of the fuel which is running down the exaust unburnt b caus of the missfire?

Solving the cause of the fuel smell will not necessarily solve the shake, but it is a KNOWN problem. Good diagnosis will always eliminate known problems first. If the fuel smell is issuing from the exhaust, then when you determine that, proceed accordingly.

FPR is bolted under a holddown bolt for the airflow meter, with outlet port coupled to the fuel distributor.

Steve