Blistering 24 sec. 0-60mph in a 124 - Page 2 - PeachParts Mercedes-Benz Forum

muleears · #16 03-28-2007, 08:07 PM

GSXR-
Swapped OVP's with the other car and no impact on the tach.

Removed the alda and it gave it some speed up to about 15 then flat again.

Will easily rev. to 5K and stay there.

Checked the EGR and heard the thunk, as you expected.

Can't check boost, I thought my Mityvac would do it but its vac. only.

I noticed that it would upshift very fast. Its in top gear by 23mph even with it floored.

Took a look at the tranny. I had checked the fluid and put in a half quart a few days previous but I checked it again and it didn't even show on the dipstick! Anyway, TWO QUARTS

later its between the lines. Went for a drive, engaged reverse quicker seemed to pull a little better from a dead stop but still upshifted way to fast. Then I got the bright idea of shifting it manually. Boy what a difference! I got my time down to 16 sec. 0-60. Its almost driveable if shifted manually. If placed in drive and floored it still upshifts way to fast and there is no kick down, even with a known good switch. If floored at 30mph it just slowly accelerates, no downshift. What would make it shift so fast? Bowden cable? Vac. leak? When I removed the alda I didn't plug the vac line, could this be it

?

Since the time has come down significantly it appears I do have some boost, correct?

85chedeng300D · #17 03-28-2007, 08:22 PM

id vote for the bowden cable. too much slack on cable means early upshift and almost no downshift. too much tension means late or high rpm upshift an and sensitive downshift.

muleears · #18 03-28-2007, 09:02 PM

which one is it and how do i adjust it?

dieseldiehard · #19 03-28-2007, 09:56 PM

Quote:

Originally Posted by muleears

2.5 turbo- Have changed filters, but not tank screen. Will check alda stuff today. My mityvac is supposed to measure pressure also, the guage shows both. Motor seems to run good, just lacking power. Could the wastegate be stuck open?

fairly common on the 603 for some reason, the flapper gets crud on it preventing it from closing all the way and the exhaust bypasses the turbo. You have to remove the turbo to get it cleaned off if thats the problem.

gsxr · #20 03-28-2007, 10:32 PM

Quote:

Originally Posted by muleears

GSXR-
Swapped OVP's with the other car and no impact on the tach. Removed the alda and it gave it some speed up to about 15 then flat again. Will easily rev. to 5K and stay there. Checked the EGR and heard the thunk, as you expected. Can't check boost, I thought my Mityvac would do it but its vac. only. I noticed that it would upshift very fast. Its in top gear by 23mph even with it floored.

Took a look at the tranny. I had checked the fluid and put in a half quart a few days previous but I checked it again and it didn't even show on the dipstick! Anyway, TWO QUARTS

later its between the lines. Went for a drive, engaged reverse quicker seemed to pull a little better from a dead stop but still upshifted way to fast. Then I got the bright idea of shifting it manually. Boy what a difference! I got my time down to 16 sec. 0-60. Its almost driveable if shifted manually. If placed in drive and floored it still upshifts way to fast and there is no kick down, even with a known good switch. If floored at 30mph it just slowly accelerates, no downshift. What would make it shift so fast? Bowden cable? Vac. leak? When I removed the alda I didn't plug the vac line, could this be it

?

Since the time has come down significantly it appears I do have some boost, correct?

Cool - we're some making progress here.

1) Sure sounds to me like the tach sensor is bad, but a voltage check at the 2-prong connector near the OVP relay would confirm this. Also clean the contacts at that plug first, see if that helps.

2) The fact that you saw a power increase with the ALDA tweak is good news. At least it's pulling away from a stop properly now.

3) Revving to 5k easily means an exhaust blockage is unlikely. That's good.

4) Tranny upshifts are controlled entirely by the Bowden cable. I suspect the Bowden cable is disconnected, broken internally, or grossly misadjusted. It's the cable that attaches to the throttle linkage and goes down to the tranny. It will be near the cruise actuator, behind the injection pump, in front of the oil filter. Vacuum controls the shift firmness, not the shift point, so if it's not slipping, flaring, or banging forget about vacuum for now.

5) What you describe sounds a lot like no boost signal to the ALDA. My old white '87 would get to 60mph in about 14 seconds with the ALDA boost pressure signal disconnected, and this would drop to about 11 seconds with the ALDA boost pressure signal present. It's pretty likely you are getting boost but it sure would be nice to confirm that.

6) Have you cleaned out the fitting on the intake manifold, and tried running a hose straight from there to the ALDA, bypassing everything else? If there's no chage with that configuration, you really need to do a boost pressure check. Might be a good excuse to upgrade to the MityVac 4050 (click here for a good price on that.)

7) With that much tranny fluid missing, I'd check for leaks. On my 300E, the O-ring where the dipstick tube goes into the tranny was bad, causing a puddle everywhere it was parked. One dollar for a new O-ring and a few hours later it was leak-free. Blast the whole area with carb cleaner if it's not too oily & dirty. If it's really bad down there, use engine cleaner and a pressure washer first. Get it all bone dry then look for where the ATF is leaking from.

muleears · #21 03-29-2007, 06:35 AM

There is slack in the bowden cable and it appears the adjustment is most/all the way out. When pulled the cable has tension on it so it appears not to be broken. Could it be stretched?

Right now the alda is off. I'll back it out 1.5 turns and reinstall this afternoon. I will then try with a vac. hose direct from the manifold to the alda. I noticed no black smoke with the alda off. Shift linkage is sloppy also. Sometimes I have to wiggle it to get it to shift into D.

The car had been sitting for 2 years, I guess it could have lost the tranny fluid over that time. I'll do a tranny service this weekend. Whats the easiest way to find the torque converter drain plug for a man with minimal tools? Do I turn the crank (clockwise when facing the front of the car) until I see the plug?

Thanks again for all the help.

85chedeng300D · #22 03-29-2007, 10:44 AM

there should be a white turn-buckle-like nut or coupling on top of the valve cover theat attatches the cable that you can turn to increase or decrease the cable tension. (hint: it should be around the rubber boot of the cable). more tension, longer upshift at higher rpm, more slack, shorter upshift at lower rpm.

muleears · #23 03-29-2007, 12:02 PM

There is no cable on top of my valve cover, remember I have a 603. The cable I believe is the bowden goes from the throttle linkage down to the transmission. It has a white adjustable nut like you said, but it is adjusted out about as far as it will go. I don't think I can take any more of the slack out of it. Do I need a new one and is it called a "kickdown cable" at Fastlane? I don't find a "bowden" in the parts list.

Thanks for the help.

2.5Turbo · #24 03-29-2007, 03:41 PM

Only on the 90-93 124.128 do transducers control boost. Shouldn't be a problem on this car.

muleears · #25 03-29-2007, 07:32 PM

Today I adjusted the alda 1.6 turns CCW and reinstalled it - no difference

Plugged manifold directly into alda - no change

Adjusted bowden all the way out - no change

Adjusted bowden all the way in - no change

When placed in drive under light acceleration it shifts to second at about 5mph, then at 20 it seems to double shift from second to fourth with no pause in third. Still no kickdown. 0-20 is good, then its fourth gear all the way. What now?

Thanks for the help.

Jim Wickham · #26 03-29-2007, 08:27 PM

if you were closer I would lend you an extra isspro guage I have sitting around that I'm using to test the same thing on my car as far as boost goes.

I also have an 87 that is in the 1 minute 0-60 class so I'm watching this post closely. I'm also going to try the 2 liter bottle as a fuel tank trick tomorrow if I get a chance.

Not trying to hi-jack the post here but I'll share whatever I come up with in the next couple of days.

85chedeng300D · #27 03-29-2007, 09:12 PM

Quote:

Originally Posted by muleears

There is no cable on top of my valve cover, remember I have a 603. The cable I believe is the bowden goes from the throttle linkage down to the transmission. It has a white adjustable nut like you said, but it is adjusted out about as far as it will go. I don't think I can take any more of the slack out of it. Do I need a new one and is it called a "kickdown cable" at Fastlane? I don't find a "bowden" in the parts list.

Thanks for the help.

oh yeah! my bad! i was talking about the 617s.

muleears · #28 03-29-2007, 09:14 PM

Thanks. I have pretty much ruled out a fuel delivery problem as it will accelerate pretty well when shifted manually, just need to figure out why its in fourth at 20.

If the bowden were broken it wouldn't retract when pulled would it? I looked at the bowden on my "good" car and it has slack in it too. I'm getting so confused, maybe I'm not even looking at the bowden

.

85chedeng300D · #29 03-29-2007, 09:34 PM

I was watching this thread closely because I used to have exactly the same problem as this one about a year ago spring of last year with my 617. here's all what I did.

1. adjusted valves to specs.
2. adjusted bowden cable, tranny modulator
3. adjusted throtle linkages, making sure it hits the stop at pedal to the metal, mine hits the stop about approx. 1/4" before touching the kickdown switch
4. alda still virgin, didn't touched it, except cleaning the banjo bolt and tubings.
5. egr, arv... and all that crap still hooked up and functioning, didn't toched any of it.
6. replaced air and 2 fuel filters.

since then, not the best but performs near perfect.
333K miles, 23 mpg combined city/hi-way drive
shifts silky-smooth at any desired rpm depending on the gas pedal pressure. 0-60 at around 15-16 secs with AC on and cold.
tranny shifts: 1-2 @ 3000, 2-3 @ 3000, 3-4 @ 4000

muleears · #30 03-30-2007, 07:27 AM

Quote:

Originally Posted by 85chedeng300D

I was watching this thread closely because I used to have exactly the same problem as this one about a year ago spring of last year with my 617. here's all what I did.

1. adjusted valves to specs.
2. adjusted bowden cable, tranny modulator
3. adjusted throtle linkages, making sure it hits the stop at pedal to the metal, mine hits the stop about approx. 1/4" before touching the kickdown switch
4. alda still virgin, didn't touched it, except cleaning the banjo bolt and tubings.
5. egr, arv... and all that crap still hooked up and functioning, didn't toched any of it.
6. replaced air and 2 fuel filters.

since then, not the best but performs near perfect.
333K miles, 23 mpg combined city/hi-way drive
shifts silky-smooth at any desired rpm depending on the gas pedal pressure. 0-60 at around 15-16 secs with AC on and cold.
tranny shifts: 1-2 @ 3000, 2-3 @ 3000, 3-4 @ 4000

1. Hydraulic lifters, no adjustment
2. Bowden- no affect, haven't touched modulator
3. Looked at linkage, not sure where stop is
4. Backed alda out 1.6 turns, slow speed improvement, 0-20 matches "good" car
5. EGR functioning and ARV still attached assume its functioning
6. Both filters replaced

Could the modulator be bad? Does it affect shift points?