Just Got Back From a Highway Run

[mannys9130]

Hi guys,

I've owned my 1984 190D 2.2 5spd for a few months now. I haven't taken it on a highway run until now. I have a lot of slop in the steering due to a worn center link. I also have a bit of a warp in the brake discs and unbalanced front tires. That made for quite an interesting drive. At 2AM though, not too many cars are on the highway so I felt ok doing a run.

A few things occured to me. The car shakes pretty good due to the off-balance front tires. The rears were installed at a shop after I bought the car and they have weights. The fronts don't have weights for some reason. Odd. The brakes pulse. I knew that from driving fast in town. I'll do a brake job when I get more money. The brakes work fine and the pulse is only noticeable above 50mph.

The most striking things are that one, I took 30 seconds to get up to 60mph. The second is that my top speed in 5th gear floored to the mat was only 80 or 85mph. I can't imagine that the om601 and 5spd takes 30 seconds to get to 60 and then tops at 80. That's just not sitting well in my head.

A while ago I made a thread asking for suggestions on an intermitent shake and rough idle. I tried a few different things (filling up all the way, lubing my linkages etc.) that were easy to do, but it still does that too.

Is that a fuel starvation problem? I changed the primary and secondary fuel filters when I got the car in July. The secondary has a few flecks in it, but it isn't clogged at all. The fuel looks good coming through the secondary filter. I fill up at Shell and add 4oz of 2 stroke oil to the tank. The fuel input and return lines are new in the engine bay. The fuel thermostat has been bypassed and the input goes right to the lift pump.

I haven't touched the filter screen but I think my next thing is to fill the tank and swap the fuel lines to blow out anything on the screen.

I don't know where I could be sucking air or restricting fuel.

I just replaced the 4 glowplugs by pulling the manifold off. I put that baby in the bathtub and scrubbed it nice and clean followed by a dishwasher cycle on pots and pans. The car is federal emissions, so the whole intake is clean now.

What do you guys think? I just find it really odd that a 4 month old filter could plug up and that the secondary could be pretty much clear. I also find it odd that the engine will rev up to redline in gear 1-3 fine, but the top speed is 80mph. It says fuel starvation, but not fuel starvation.

[vstech]

Originally Posted by mannys9130

Hi guys,

I've owned my 1984 190D 2.2 5spd for a few months now. I haven't taken it on a highway run until now. I have a lot of slop in the steering due to a worn center link. I also have a bit of a warp in the brake discs and unbalanced front tires. That made for quite an interesting drive. At 2AM though, not too many cars are on the highway so I felt ok doing a run.

A few things occured to me. The car shakes pretty good due to the off-balance front tires. The rears were installed at a shop after I bought the car and they have weights. The fronts don't have weights for some reason. Odd. The brakes pulse. I knew that from driving fast in town. I'll do a brake job when I get more money. The brakes work fine and the pulse is only noticeable above 50mph.

The most striking things are that one, I took 30 seconds to get up to 60mph. The second is that my top speed in 5th gear floored to the mat was only 80 or 85mph. I can't imagine that the om601 and 5spd takes 30 seconds to get to 60 and then tops at 80. That's just not sitting well in my head.

A while ago I made a thread asking for suggestions on an intermitent shake and rough idle. I tried a few different things (filling up all the way, lubing my linkages etc.) that were easy to do, but it still does that too.

Is that a fuel starvation problem? I changed the primary and secondary fuel filters when I got the car in July. The secondary has a few flecks in it, but it isn't clogged at all. The fuel looks good coming through the secondary filter. I fill up at Shell and add 4oz of 2 stroke oil to the tank. The fuel input and return lines are new in the engine bay. The fuel thermostat has been bypassed and the input goes right to the lift pump.

I haven't touched the filter screen but I think my next thing is to fill the tank and swap the fuel lines to blow out anything on the screen.

I don't know where I could be sucking air or restricting fuel.

I just replaced the 4 glowplugs by pulling the manifold off. I put that baby in the bathtub and scrubbed it nice and clean followed by a dishwasher cycle on pots and pans. The car is federal emissions, so the whole intake is clean now.

What do you guys think? I just find it really odd that a 4 month old filter could plug up and that the secondary could be pretty much clear. I also find it odd that the engine will rev up to redline in gear 1-3 fine, but the top speed is 80mph. It says fuel starvation, but not fuel starvation.

this made a HUGE difference in power for me.
I'd first douse the tank with a quart of Diesel Clear to eat up the sediment/fracked diesel... then I'd drive to JUST SHY OF 1/2 tank, and swap the lines back, and fill the car back up with fuel.

[Walkenvol]

I have a 2.2L auto (so no overdrive gear) and I've hit 90 mph and it had more left. It will get 0 to 60 much quicker than 30 seconds although I've never officially timed it.

If you have good compression, then my guess on your performance issues would be fuel restriction. You can try the Vstech route or pull the tank and clean the tank screen. Carefully check the fuel lines from the tank to the IP to make sure your not sucking in air. Once your confident that the fuel is flowing freely, the next step would be to pull/recondition the injectors and verify the timing.

[psaboic]

One idea..... IF you can, take a 2 gallon jug and fill it with FRESH diesel. Run a hose from it directly to the fuel intake hose on the IP, and go for a run and see if that makes a difference. That way you will have eliminated basically the entire car fuel system except for the pump and the filters. Of course unless you run the fuel return back to the 2 gallon can as well, you will deplete that 2 gallons pretty quickly as it will be routed back to the car's tank.

I've done that before and it helped to figure out a fuel issue I was having

[mannys9130]

Thank you guys very much for the replies.

I took the car to my favorite Shell and filled the tank ALMOST (I ran out of money.) to the top. I calculated my mileage at 38.2 MPG almost all city driving.

Then I came home and swapped the fuel lines coming into and out of the engine bay. Driving down the street I saw no change. I drove down a fast road (45 so I did 55) and saw no change. Then I jumped back on the highway and did another run. Took just as long as last time to get up to 60 and since it is 8:30pm I was scared that I was going to get rear ended! I drove about 50 miles from swapping the lines, some city driving, some highway driving, and finished with more fast city driving. No difference at all.

The car still topped out at 80 in 5th gear. I could drive at 60 pretty nicely but at 70 it starts to get upset and at 80 it's very taxed. Pedal to the floor activating the kickdown/full load switch.

After I pulled off of the highway and sat at the off ramp, the car started to do its rough idle and felt like it was missing a cylinder. If I just barely push the gas pedal to bring the rpms up 100-200 or so, it smooths out completely.

The only fuel lines that I haven't touched are the return lines on the injectors (they look ok and don't weep), the clear plastic lines off the IP, and the lines that are under the tank.

I THINK compression is ok, since it starts pretty good and doesn't smoke. I might get a puff of white smoke at a cold start 50*F in the morning, but I figure the injectors are tired.

Now what do you guys think? I hope I can figure this out an get my power back. As it stands, my sister's automatic 2.2 with intact Cali egr is faster then my car.

[ah-kay]

Originally Posted by mannys9130

I THINK compression is ok, since it starts pretty good and doesn't smoke. I might get a puff of white smoke at a cold start 50*F in the morning, but I figure the injectors are tired.

I suspect it is low compression in 1 or 2 cylinders. I have a 190D and it started on the 1st spin but exhibited rough idle at cold and hot. It smoothed out if I reved the engine, acceleration was OK. I did a compression test and cyl 1 was found to be < 150psi while the others are at > 400. I overhauled the engine and now it runs like a champ. I am glad I did as the head cylinder gasket was tired and brittle. I highly recommend you to do a compression test, ideally hot but cold is OK. You have nothing to lose.

[mannys9130]

I'll see if I can get everything together to do a compression test. You're right, for the cost of 4 heat shields it'll be good info to know.

My "ear compression tester" says it's ok, but that's really quick and dirty. What I mean is, when I changed the filters the first week I got the car, the cranking I did while bleeding the air out sounded even and normal. CHUG, CHUG, CHUG, CHUG, CHUG, CHUG. If the compression was low on one cylinder wouldn't it sound like a hiccup or gallop in the cranking. CHUG, CHUG, chug, CHUG.

You know what I mean? Hopefully I can get a job soon and have money to do things. I'm still looking for something I can do after 1 year has past since I was hit by a truck on my motorcycle. It's tough.

Thanks!

[mannys9130]

I just had an epiphany.

Since it's so hot here in Tucson, I grounded my fan clutch to the intake manifold so that it is always on. I figured I would take the hit in fuel economy just to keep the engine cool.

As it is, the car sits right above the 80 mark and at the highest right smack in the middle between 80 and 100. Now that it's getting cold, I might undo that.

HOWEVER, do you think the engine fan being on all the time would create a big enough drag at 3000 to 3500 rpm to sap the power needed to go faster then 80? I doubt it, but what do I know?

[Walkenvol]

Originally Posted by mannys9130

the car started to do its rough idle and felt like it was missing a cylinder. If I just barely push the gas pedal to bring the rpms up 100-200 or so, it smooths out completely.

Only time mine has ever had a rough idle was when a hard line from the IP to an injector developed a leak, but that's impossible to miss if you open the hood.

If your getting 38 mpg's in city driving, then I can't see the brakes dragging as that should make your mileage suffer.

You should be able to do the compression test via the glow plug holes so no new crush washers required.

You still need to verify there's no fuel restictions as described earlier with the alternate fuel source, then verify the compression, then verify the timing.....got to be one of those 3.

[oldsinner111]

you can be surprised how much junk is clogged at tank screen,over the years..But you bypassed the system,I would suspect weak fuel pump.Or you can add a inline electric pump,if cheaper than lift pump,I've done that.

[psaboic]

Like I said earlier, try running it from a fuel can instead of the tank and see if that changes things. That and try fresh filters. That should tell you if it is fuel system related or not (except for the IP of course)