Ok, I searched and searched and I know I am going to get yelled at because it is probably right in front of my face. I even looked at the service manual links to no avail. The other years seem to have different routing of the myriad of vacuum lines (which are all brittle as heck). A number of them disappear under the intake manifold and I get the feeling I have to pull the engine to get to them all!
Anyway, sorry if this diagram is out there already - I greatly appreciate any assistance finding it!
Thanks!
sj
P.S. I have read all about the where and hows to getting new lines, but first I need to see which ones I need (other than the two obvious ones that are broken).
Thanks for the picture! The nipple is snapped off right at the housing on the FP regulator which is why I did not see it before. Could this be the cause of my surging acceleration?
It could be. If the nipple is broken you may have to replace the FPR. I tried once to repair it and couldn't do it. Maybe someone else has done it and will chime in.
that nipple provides a way for pressurized fuel upon a "failure" of the pressure regulator. Fuel would flow down that line and into the right bank. So while primitive, can be effective in preventing fire on top of the engine. Don't stress over it and yes, you can get a new nipple (pm luckymike for p/n) and install it. rolling the dice, but 2 out of 100 have in tact FPR disaster nipples LOL
Surging is normal during warm up process. The action continues to a lesser degree at temperature as well as the CIS and O2 system send data to the computer, adjusting the mix of air/fuel to maintain a level. The ac draw of power will cause the surge, a bad coil could as well, a vacuum leak, leaky injectors. Bad idle air valve or idle speed relay. So so the basics. Cheaply, have a smoke test performed if you have high idle to determine leak locations.$
Free stuff is to be sure your duty cycle is proper and that is diy. Clean the idle air valve, inspect all rubber on the upper manifold and if it is hard, replace it. The rubber you see is easy, what you don't see is between the upper and the lower, several rubber donuts, throttle plenum too. You may need to spend but don't spend recklessly, diy research is cheap and simple diy.
sure thing, we are all experienced to one degree or another (meaning we have been here and done this more than once) and just want you to know that this is an old car, analog in a digital world, and 25 year old stuff wears out. You can throw a ton of money at things, but fix what you need to fix by checking. Rule of thumb, rubber parts from MB lasted long, aftermarket will not. Spend up for MB rubber, seals or Lemfoerder suspension pieces. mboemparts.com is Mercedes out of Illinois, and they do a decent pricing. and by all means be sure you just don't fix or replace that crap without checking it. So many waste money fixing things that are not broken. Fix what is broken only, safety first and your wallet will thank you.
The most expensive car you ever own is a cheap Mercedes.....
OP, you may want to clarify what you mean by 'surging'. Is it at idle, under load, cold engine, after running for some time, all the time, after start during warm up?
Plenty of knowledge here to help you if you provide enough info.
Stumbling may be a better word. Does it at idle a lot when cold, when warm, stumbles some at stop lights, hesitates a little here and there on acceleration, but once moving at a steady rate seems pretty smooth. Mostly happens in changes (increase) in acceleration.
on cold start, you get an increased fuel amount sent to the distributor. If injectors leak, over night and that occurs, you "can" get that stumbling for that reason, but there are others. Checking the duty cycle tells you much about things and again this process can be a rat hole. It also may suggest loss of vacuum, by leaking tubes or by electronic means (ICV ISCR) again duty cycle. Get a decent multi meter and get to work checking things out.
I also recommend please, please photos uploaded to the BW site directly, rather than any image hosting site, as the valuable information can be lost for good once the site changes its software/addressing…. or the account becomes deleted etc.
Ok, I printed off the big duty cycle test thread and did some testing. If I am reading correctly, it is pointing to my O2 sensor. I get 50.3 all the time. Jumps UP when I throttle it, but always settles back to 50 even when it is warmed up. Started out at 30 with the key on but not started. I don't know how old the O2 sensor is, and it is connected (I verified this). It's not that expensive and relatively easy to replace. Is it worth just swapping out?
They last 60k +|~ 20k.
Get Bosch and unless you want to splice wires, take the more costly option
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