This is the second problem on my 1996 E300 Diesel. I bought this car about two months ago and have already driven it 5000 miles. When I bought it, I would notice some stumbling / power fluctuation at low highway speeds but the engine starts and idles about as smooth as could be. When wide open, she accelerates smooth with moderate soot out the tailpile to be expected. When I checked the clear fuel lines I found some minute air bubbles with the engine running and when the engine was shut off I noticed an inch of air at the line going into or from the top of the prefilter. AhHa I said; must be air and need new O rings and I'll swap out the filters and everything will be solved. NOT!!! The car engine still stumbles around 2500 revs under load - if you hold it at 2500 in neutral you can't tell anything is wrong. The idle could be a bit smoother but its already smoother than most gas engines. Question, is, does anyone know if a tiny bit of air can cause this and if so, where the hell is the air coming from; the gasket on the fuel heat sensor block?
Please help.... Others suggestions have been great - I solved my front end knock with advice from this website - now just two more problems and Im out of everyones hair...
An inch of air in the pipe leading to the prefilter is normal when the engine is stopped. They all have this, and it doesn't cause any problems. If you don't see fuel in that pipe after the engine has been shut off for a while, you have a leak.
I'd check the resonance flaps, but this is a guess.
At steady throttle moderate speeds (say 45 to 65 or so), does your car feel like it is surging, or like the throttle position is being varied as you drive?
Dear Rick, you've got it - this is exactly what it feels like. Only at moderate highway speeds from 45 to I'd say 65 - does not seem to do this at higher speeds like 80 seems to be smooth. Tell me you know what is causing this and please don't tell me the injection pump fuel rack is worn from years of running at that speed (which is what I fear).
And Matt, thank you for your clarification on the 1 inch of air; never see any more than that.
EGR.....It sounds like a sticking EGR Valve.... this happens alot with this model. to test , disconnect the vacuum hose fromt he EGR valve and plug the hose. read my other post today about this same probem...aj
If you have the surging at steady throttle problem, then, yes it is related to the EGR valve, but it is not the EGR valve itself. The problem is the vacume control solonoid valves which control the EGR position. This is a very common problem on the E300D, especially, 96 and 97 models. The valves are easy to get to and to change. There are two identical valves located side by side on the right inner fender well (more or less across and somewhat below the EGR and intake manifold. They are black, plastic, and have several connections and hoses coming from them. Change them both (often changing the one which directly connects to the EGR will also take care of the issue, but there is some interelation between the two valves). They are about $75 or so each and can be changed out in about 10 minutes. Be sure you label the hoses and connections so you get everything plugged back into the correct place. Your surging at steady throttle will go away.
Any idea where I can get that part (EGR vacuum transducer) for $75. My local dealer in Seattle wants $130. A part # would be great help. This sounds exactly what my car is doing. It also has a EGR check light on.
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1997 E300
2001 VW TDI
1996 Dodge 1 Ton Cummins
2006 Dodge 1 Ton Cummins
Linear Mode
