606.962 EGR delete question. - PeachParts Mercedes-Benz Forum

citationtech · #1 08-22-2011, 04:32 PM

i preformed the three component egr delete on my '98 e300 a couple months ago. no check engine light since the mod. today after i shut it down i could hear a vacuum bleed. it was coming from the egr transducer. i pulled the top hose off, the one that connects to the egr, and it had vacuum. started the car and it was drawing strong vacuum from the nipple on the transducer. with the transducer electrically disconnected shouldn't it be disabled? all the hoses are connected and electrical disconnected per the modification instructions. is this normal operation or has my transducer possibly failed in a "open" position? seems to me that the egr would be normally closed and vacuum would open it on demand, so with vacuum still present from the transducer it is still functioning, or maybe i'm thinking about this totally backwards. input???

KarTek · #2 08-22-2011, 06:45 PM

Make sure that no one, at any time, switched the order of the vacuum lines. The supply line goes on the center, top connector.

citationtech · #3 08-22-2011, 07:31 PM

the top the transducer has two nipples. one labeled "VAC" this hose routes to the check valve/brake booster. the larger diameter nipple "OUT" connects directly to the egr valve via hose. on the bottom of the transducer there is a hose that vents to atmosphere via the filter. looks correct according to the diagram and makes sense in my mind. i swapped transducers from the turbocharger waste gate and still have a constant vacuum draw from the line for the egr. again, the transducer is eclectically disconnected. is this normal operation WITH THE MOD or is there something going on with my transducer? i was under the impression that with the transducer electrically disconnected it would not function thus keeping the egr closed at all times.

KarTek · #4 08-22-2011, 08:50 PM

That's interesting. I believe the transducer works off PCM. If it's disconnected, it may hang "slack" and allow some vacuum through.

On mine, I simply plugged the line going to the EGR so there's no chance of it being actuated.

citationtech · #5 08-22-2011, 09:36 PM

i'll give that a try and report back. anyone have a specification as to what pressure is required to open the egr in a normal cycle?

citationtech · #6 08-23-2011, 08:27 PM

i capped the vacuum connection from the transducer to the egr today and logged about 100 miles without any adverse effects on the car. it may be phycological but she sure seems preform better than before! this is something i definitely should have done initially to completely separate the transducer from the egr - as KarTec pointed out. i still highly recommend the electrical egr delete, it's a gem!