Hello all.

For the last month I have been chasing a 'loss of power' issue that has gone as far as repeated stalling and 'no start'. The last couple weeks, there has been no stalling and even on cold mornings it starts right up with out being plugged in.

I have replaced the fuel filters and am about to do so again.

A little history.

I acquired this car from my Aunt in April of this year. I did a precursory once over and replaced filters, fluids, brake pads, rotors, brake fluid flush, air filter, and new tires. A couple electrical items repaired and I have a reasonably functioning commuter car sans a/c.

Shortly into the summer a hard starting issue occurred that found me replacing the delivery valves. Problem solved. This was followed shortly after with new return hoses as there were leaks from the injectors.

Fast forward to early October and now I find it difficult to keep up with highway traffic at 70-80mph. What required part throttle this summer is now FULL throttle. This is now moved onto "barely able to go 60mph" and quite dangerous on I95 where traffic goes 80-85mph.

I have replaced all the fuel lines under the hood thinking I had an air leak issue. (*edit) In doing so, I bypassed the fuel t-stat. I will later reconnect it. (* end edit). Next I drained the tank and pulled the in tank prefilter/screen. How the heck this thing screens anything is beyond me. I cant see the pick up tube through the hole in the bottom of the tank, and there is no place for anything to attach to the screen assembly. (will update with photo later).

Draining the tank:
The fuel coming out of the tank looks as clean as I would expect fuel to be. 100% clean. no dirt, no little bits, nothing.

Just for kicks, I am putting the screen back in, returning the drained fuel back to the tank, and putting in another new filter set.

My fear is that all of this is pointing to a new lift pump. Is there anyway to test the lift pump? I hate to purchase a new one and have this not be the problem.

Thanks in advance for any help.


Note: I am also soon looking for a thread describing tranny service. I am assuming I just drop the pan, unbolt the filter, reassemble and then add DexIII to the dipstick tube. (?)
I need to also do this for our W210, but the dipstick is locked.

Attached Thumbnails

     

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