Ok folks, looking for fresh ideas here (long explanation)...
Before I start, let me say that I do own a Bentley, have searched exhaustively, and run most of the tests on the Motronic trouble-shooting link.
Car is the Hassliches Entlein, 1988 SETA 528e. I recently replaced the waterpump, and since, have had driveability problems. Specifically the Ugly Duckling won't take WOT and bogs under heavy load/above 3krpm. Starts up and idles fine and I can generally accelerate fine up to 3k in any gear if i take it easy on the throttle. Occassionally it bogs at lower rpm's but if I power off for a minute and let it sit (I have gotten good at counting to 60), driveability will improve some. The car was losing a lot of coolant through the bad wp before I changed it but I think I was careful enough to keep it from overheating. The problem might have been present before the wp change but I was so pre-occupied with the obvious problem I might not have noticed.
First thought was ignition. I have pulled all the plugs and good spark to all, no noticeable differences between the plugs, relatively normal. Compression is low but consistent (+/-130 all cylinders, motor has 250k+). Cap and rotor looked ok but I made sure contacts were clean and shiny. Problem persists, No vacuum leaks I can detect,
I noticed some white smoke from the tailpipe, so I started thinking maybe HG. I just installed BillyBoat exhaust and there is an air leak between converter and muffler that I haven't dealt with yet - condensation entering? Not sure. Driveability was suffering before the exhaust change but white smoke may have started after, I don't recall notocing it before. Anyway, I was seeing some small bubbles in the coolant and the coolant I had replaced with the WP job not long ago was looking a little cloudy, but no evidence in oil anywhere. I drained the coolant and removed the overflow bottle and there was kind of some "rocks" in there. Removed that crap whatever it was and flushed system again real well. New coolant has remained pretty clear and no significant coolant loss but a little seems to be going somewhere. Just in case I did a block test on the coolant and it remained blue in a number of scenarios. Today it was drizzling and car ran a lot better but there was a lot of white smoke from the exhaust but didn't necessarily smell sweet or like coolant.
So originally I was thinking fuel delivery. Under-body and in-tank pumps both replaced with known good and are pumping fuel, underbody pump is loud. Filter was also changed. Tested fuel pressure and its a little low (+/-low 30's). There is some rust in the tank and I have seen a decent amount of rust particles on the intank pre-filter so I'm going to pull the tank and see if it can be cleaned or replaced. Could be injectors but the pressure is a little low going to the rail so that test will come after the tank.
So I will continue to move thru the process but here are my immediate questions:
1) I know HG leak can affect driveability in many ways, are my symptoms like anyone has experienced with a bad HG
2) For some reason, I just have a feeling the HG is bad, is it possible for HG to be bad without milkshake in oil, and no combustion gasses in coolant? I know it sounds ridiculous, but the white smoke and driveability...
3) How much rust in tank would cause driveability problems this severe?
4) About the only sensor I haven't checked is the coolant temp sensor, does this sound feasible? I have double checked o2 , cps, etc.
5) Why such severe improved driveability when it is damp outside.
Please feel free to ask whatever questions about what tests I've conducted and how. Thanks for any and all input.
driveability conundrum
-
spencefree
- Posts: 119
- Joined: Apr 26, 2011
- Location: Hill Country Texas
Re: driveability conundrum
I know, I know...its kind of like "where do I start?"
So i removed the tank and it had quite a bit of rust. I used the old apple cider vinegar and sheet rock screws trick and was able to remove most of the rust. Remove tank, flush with h2o numerous times, add apple cider vinegar and let sit for about 12 hrs, drain vinegar through filter to see what you get. Put sheet rock screws (some say bicycle chain, doesn't matter as long as its abrasive - I had no problem shaking out the screws and getting the last few with a magnet. Shake that sh*t, drain through a filter as many times as your body can take it or until no crud comes out. Get rid of the cider and remove abrasive material, flush repeatedly with h2o. Fill a bucket with h2o and add baking soda, more is better. Drain whatever water is in there and neutralize the acidity of the vinegar with the baking soda water and then flush it out.
I then hooked up my shop vac to the fuel pump inlet with some duct tape (put something in the filler neck to prop the flap open) to draw air through until the tank was dry of moisture. Once dry, I took a look with a flashlight and a mirror and the tank was surprisingly free of rust. I then took the big bottle of WD40 and liberally coated the inside of the tank.
While I can't say what the long term results will be (will rust return)? I can say that drive-ability has improved dramatically. In the meantime, I will be sourcing a clean tank (the piknpulls puncture the tanks) for a more permanent fix.
Still can't explain slight coolant loss or white smoke from tailpipe but I'm chalking it up to the exhaust gap for now. FWIW, a good running seta coupled with a throaty BillyBoat exhaust makes you feel like you are powerful.
So i removed the tank and it had quite a bit of rust. I used the old apple cider vinegar and sheet rock screws trick and was able to remove most of the rust. Remove tank, flush with h2o numerous times, add apple cider vinegar and let sit for about 12 hrs, drain vinegar through filter to see what you get. Put sheet rock screws (some say bicycle chain, doesn't matter as long as its abrasive - I had no problem shaking out the screws and getting the last few with a magnet. Shake that sh*t, drain through a filter as many times as your body can take it or until no crud comes out. Get rid of the cider and remove abrasive material, flush repeatedly with h2o. Fill a bucket with h2o and add baking soda, more is better. Drain whatever water is in there and neutralize the acidity of the vinegar with the baking soda water and then flush it out.
I then hooked up my shop vac to the fuel pump inlet with some duct tape (put something in the filler neck to prop the flap open) to draw air through until the tank was dry of moisture. Once dry, I took a look with a flashlight and a mirror and the tank was surprisingly free of rust. I then took the big bottle of WD40 and liberally coated the inside of the tank.
While I can't say what the long term results will be (will rust return)? I can say that drive-ability has improved dramatically. In the meantime, I will be sourcing a clean tank (the piknpulls puncture the tanks) for a more permanent fix.
Still can't explain slight coolant loss or white smoke from tailpipe but I'm chalking it up to the exhaust gap for now. FWIW, a good running seta coupled with a throaty BillyBoat exhaust makes you feel like you are powerful.
-
spencefree
- Posts: 119
- Joined: Apr 26, 2011
- Location: Hill Country Texas
Re: driveability conundrum
I know, I know...its kind of like "where do I start?"
So i removed the tank and it had quite a bit of rust. I used the old apple cider vinegar and sheet rock screws trick and was able to remove most of the rust. Remove tank, flush with h2o numerous times, add apple cider vinegar and let sit for about 12 hrs, drain vinegar through filter to see what you get. Put sheet rock screws (some say bicycle chain, doesn't matter as long as its abrasive - I had no problem shaking out the screws and getting the last few with a magnet. Shake that sh*t, drain through a filter as many times as your body can take it or until no crud comes out. Get rid of the cider and remove abrasive material, flush repeatedly with h2o. Fill a bucket with h2o and add baking soda, more is better. Drain whatever water is in there and neutralize the acidity of the vinegar with the baking soda water and then flush it out.
I then hooked up my shop vac to the fuel pump inlet with some duct tape (put something in the filler neck to prop the flap open) to draw air through until the tank was dry of moisture. Once dry, I took a look with a flashlight and a mirror and the tank was surprisingly free of rust. I then took the big bottle of WD40 and liberally coated the inside of the tank.
While I can't say what the long term results will be (will rust return)? I can say that drive-ability has improved dramatically. In the meantime, I will be sourcing a clean tank (the piknpulls puncture the tanks) for a more permanent fix.
Still can't explain slight coolant loss or white smoke from tailpipe but I'm chalking it up to the exhaust gap for now. FWIW, a good running seta coupled with a throaty BillyBoat exhaust makes you feel like you are powerful.
So i removed the tank and it had quite a bit of rust. I used the old apple cider vinegar and sheet rock screws trick and was able to remove most of the rust. Remove tank, flush with h2o numerous times, add apple cider vinegar and let sit for about 12 hrs, drain vinegar through filter to see what you get. Put sheet rock screws (some say bicycle chain, doesn't matter as long as its abrasive - I had no problem shaking out the screws and getting the last few with a magnet. Shake that sh*t, drain through a filter as many times as your body can take it or until no crud comes out. Get rid of the cider and remove abrasive material, flush repeatedly with h2o. Fill a bucket with h2o and add baking soda, more is better. Drain whatever water is in there and neutralize the acidity of the vinegar with the baking soda water and then flush it out.
I then hooked up my shop vac to the fuel pump inlet with some duct tape (put something in the filler neck to prop the flap open) to draw air through until the tank was dry of moisture. Once dry, I took a look with a flashlight and a mirror and the tank was surprisingly free of rust. I then took the big bottle of WD40 and liberally coated the inside of the tank.
While I can't say what the long term results will be (will rust return)? I can say that drive-ability has improved dramatically. In the meantime, I will be sourcing a clean tank (the piknpulls puncture the tanks) for a more permanent fix.
Still can't explain slight coolant loss or white smoke from tailpipe but I'm chalking it up to the exhaust gap for now. FWIW, a good running seta coupled with a throaty BillyBoat exhaust makes you feel like you are powerful.
-
spencefree
- Posts: 119
- Joined: Apr 26, 2011
- Location: Hill Country Texas
Re: driveability conundrum
I know someone will ask, yes fresh filter. Also, new tanks are like $600. I may post in the wanted but does anyone know a good source for tanks? Mine didn't seem that rusty overall so I'm wary of buying another 25yo used tank.
Thanks.
Thanks.