power loss problem making me crazy
power loss problem making me crazy
My car is suffering from power loss on long hills or when really pushing on the high way, all of a sudden it would loose alot of power and barely hold 55MPH on small grade. The car runs perfectly smooth though, even at idle after stopping, and starts easy too, but the powerloss problem is abrupt and dramatic.
It do not think it is a fuel supply issue or an air issue or restriction, I have checked/replaced everything and nothing made a difference. Fuel sys is now plumbed stock, I replaced the LP (which was fine), return banjo and primer pump today, Fuel PSI at around 13, all hoses are good, return lines, new filters, screen in tank checked, etc. fuel sucks easy and air free with mityvac. The way it cut s power feels different from air, once it does this is stays this way until it sits and is restarted. Its done it for a while now and has gotten worse, I have done everything including running it off of a jug under the hood. It only seems to happen once the car is warmed up driving for 10 min or so, does not seem to happen when cold.
Tonight I replaced the Alda and switchover valve from my parts car thinking this was causing the fuel cut. I did not get it on the long hill or highway yet, but it did not have the problem on another shorter hill that it usually did (I went up and down it several times).
can a malfunctioning Alda system cause such a dramatic cut in fuel? I've seen malfunctioning ALDA before and this seems like more, but something is (or was) cutting off alot of fuel.
I'll know if its fixed tomorrow when I drive to work. Been driving me crazy, spent another beautiful weekend in the shop.
And something I learned today is make sure the dipstick is all the way in!
On one of my many testdrives today, I had oil blasting out of a small vent hole near the top of dipstick tube, pissed out like 4qts by the time I noticed it at the top of the mountain and it made a hell of a mess!
The breather seems fine, air is routed back into intake (which is always under vacuum?) and utilizes a catch can. I cannot see how the set up can not flow adequetly to vent the CC under any condition.
The problem has never happened before and has not re occurred, I probably just did not put it in all the way.
Has anyone ever noticed that oil will fill the tube when revved up with no dipstick???
(07-19-2009, 11:37 PM)GileadGarage My car is suffering from power loss on long hills or when really pushing on the high way, all of a sudden it would loose alot of power and barely hold 55MPH on small grade. The car runs perfectly smooth though, even at idle after stopping, and starts easy too, but the powerloss problem is abrupt and dramatic.
It do not think it is a fuel supply issue or an air issue or restriction, I have checked/replaced everything and nothing made a difference. Fuel sys is now plumbed stock, I replaced the LP (which was fine), return banjo and primer pump today, Fuel PSI at around 13, all hoses are good, return lines, new filters, screen in tank checked, etc. fuel sucks easy and air free with mityvac. The way it cut s power feels different from air, once it does this is stays this way until it sits and is restarted. Its done it for a while now and has gotten worse, I have done everything including running it off of a jug under the hood. It only seems to happen once the car is warmed up driving for 10 min or so, does not seem to happen when cold.
Tonight I replaced the Alda and switchover valve from my parts car thinking this was causing the fuel cut. I did not get it on the long hill or highway yet, but it did not have the problem on another shorter hill that it usually did (I went up and down it several times).
can a malfunctioning Alda system cause such a dramatic cut in fuel? I've seen malfunctioning ALDA before and this seems like more, but something is (or was) cutting off alot of fuel.
I'll know if its fixed tomorrow when I drive to work. Been driving me crazy, spent another beautiful weekend in the shop.
And something I learned today is make sure the dipstick is all the way in!
On one of my many testdrives today, I had oil blasting out of a small vent hole near the top of dipstick tube, pissed out like 4qts by the time I noticed it at the top of the mountain and it made a hell of a mess!
The breather seems fine, air is routed back into intake (which is always under vacuum?) and utilizes a catch can. I cannot see how the set up can not flow adequetly to vent the CC under any condition.
The problem has never happened before and has not re occurred, I probably just did not put it in all the way.
Has anyone ever noticed that oil will fill the tube when revved up with no dipstick???
(07-19-2009, 11:37 PM)GileadGarage My car is suffering from power loss on long hills or when really pushing on the high way, all of a sudden it would loose alot of power and barely hold 55MPH on small grade. The car runs perfectly smooth though, even at idle after stopping, and starts easy too, but the powerloss problem is abrupt and dramatic.
It do not think it is a fuel supply issue or an air issue or restriction, I have checked/replaced everything and nothing made a difference. Fuel sys is now plumbed stock, I replaced the LP (which was fine), return banjo and primer pump today, Fuel PSI at around 13, all hoses are good, return lines, new filters, screen in tank checked, etc. fuel sucks easy and air free with mityvac. The way it cut s power feels different from air, once it does this is stays this way until it sits and is restarted. Its done it for a while now and has gotten worse, I have done everything including running it off of a jug under the hood. It only seems to happen once the car is warmed up driving for 10 min or so, does not seem to happen when cold.
Tonight I replaced the Alda and switchover valve from my parts car thinking this was causing the fuel cut. I did not get it on the long hill or highway yet, but it did not have the problem on another shorter hill that it usually did (I went up and down it several times).
can a malfunctioning Alda system cause such a dramatic cut in fuel? I've seen malfunctioning ALDA before and this seems like more, but something is (or was) cutting off alot of fuel.
I'll know if its fixed tomorrow when I drive to work. Been driving me crazy, spent another beautiful weekend in the shop.
And something I learned today is make sure the dipstick is all the way in!
On one of my many testdrives today, I had oil blasting out of a small vent hole near the top of dipstick tube, pissed out like 4qts by the time I noticed it at the top of the mountain and it made a hell of a mess!
The breather seems fine, air is routed back into intake (which is always under vacuum?) and utilizes a catch can. I cannot see how the set up can not flow adequetly to vent the CC under any condition.
The problem has never happened before and has not re occurred, I probably just did not put it in all the way.
Has anyone ever noticed that oil will fill the tube when revved up with no dipstick???
(07-20-2009, 12:47 PM)winmutt Bypass the switchover valve and report back.
(07-20-2009, 12:47 PM)winmutt Bypass the switchover valve and report back.
check to make sure the fitting on the manifold isn't plugging up IE the banjo bolt on the rear to the ALDA line! if it plugs up it will cause this
(07-20-2009, 09:21 PM)willbhere4u check to make sure the fitting on the manifold isn't plugging up IE the banjo bolt on the rear to the ALDA line! if it plugs up it will cause this
(07-20-2009, 09:21 PM)willbhere4u check to make sure the fitting on the manifold isn't plugging up IE the banjo bolt on the rear to the ALDA line! if it plugs up it will cause this
with out boost they are dogs! I could get my 300sd to 70 mph floored on flat ground with out boost but it was working hard for it with out boost the alda wont add enough fuel to make good power! no boost and no fuel = slow!!!
Today I bypassed the switchover valve, all is clear to Alda. Alda was replaced with one from another pump, stock setting.
I also plugged the wastegate hose temporarily just to check the wastegate functionality. As expected, my boost would easily peg the 15LB gauge. I drove the car easy with boost not exceeding 12 or so. I still had the problem occur - though not as bad. When the problem happened, I could only get around 8PSI at WOT so the car did not dog quite as bad as it did.
Something seems to be cutting off my fuel and I don't know what, or the wastegate is opening and hanging up a bit? What the best way to check the wastegate?
The EGR is blocked so I know thats not part of the prob.
I'll probably turn up the new Alda a bit to see how it responds, but it still has the same problem as with the other Alda. I'm also going to install a manual boost controller which I've been meaning to do.
Good to know that they are that slow with no turbo, mine would struggle for 70 on flat ground too with no boost
Thanks
I'm still at a loss, but atleast it is driveable (for me, not the wife)
(07-21-2009, 05:21 PM)GileadGarage Today I bypassed the switchover valve, all is clear to Alda. Alda was replaced with one from another pump, stock setting.
I also plugged the wastegate hose temporarily just to check the wastegate functionality. As expected, my boost would easily peg the 15LB gauge. I drove the car easy with boost not exceeding 12 or so. I still had the problem occur - though not as bad. When the problem happened, I could only get around 8PSI at WOT so the car did not dog quite as bad as it did.
Something seems to be cutting off my fuel and I don't know what, or the wastegate is opening and hanging up a bit? What the best way to check the wastegate?
The EGR is blocked so I know thats not part of the prob.
I'll probably turn up the new Alda a bit to see how it responds, but it still has the same problem as with the other Alda. I'm also going to install a manual boost controller which I've been meaning to do.
Good to know that they are that slow with no turbo, mine would struggle for 70 on flat ground too with no boost
Thanks
I'm still at a loss, but atleast it is driveable (for me, not the wife)
(07-21-2009, 05:21 PM)GileadGarage Today I bypassed the switchover valve, all is clear to Alda. Alda was replaced with one from another pump, stock setting.
I also plugged the wastegate hose temporarily just to check the wastegate functionality. As expected, my boost would easily peg the 15LB gauge. I drove the car easy with boost not exceeding 12 or so. I still had the problem occur - though not as bad. When the problem happened, I could only get around 8PSI at WOT so the car did not dog quite as bad as it did.
Something seems to be cutting off my fuel and I don't know what, or the wastegate is opening and hanging up a bit? What the best way to check the wastegate?
The EGR is blocked so I know thats not part of the prob.
I'll probably turn up the new Alda a bit to see how it responds, but it still has the same problem as with the other Alda. I'm also going to install a manual boost controller which I've been meaning to do.
Good to know that they are that slow with no turbo, mine would struggle for 70 on flat ground too with no boost
Thanks
I'm still at a loss, but atleast it is driveable (for me, not the wife)
(07-19-2009, 11:37 PM)GileadGarage Has anyone ever noticed that oil will fill the tube when revved up with no dipstick???
(07-19-2009, 11:37 PM)GileadGarage Has anyone ever noticed that oil will fill the tube when revved up with no dipstick???
(07-22-2009, 04:06 PM)totaldisaster(07-19-2009, 11:37 PM)GileadGarage Really, CC Pressure will somehow limit fuel? I have to think about that one. I know I have some blowby, always have. But it does not seem too bad and I thought it is vented well enough.
Come to think of it, I do smell some vapor after the prob occurs.
Interesting, I'll vent to atm before my drive home
Thanks.
Has anyone ever noticed that oil will fill the tube when revved up with no dipstick???
this should not be happening, it means you have crank pressure - it could easily cut off your fuel supply. You are not breathing well enough. Vent to atm for a trial run or once you notice the problem occurring.
(07-22-2009, 04:06 PM)totaldisaster(07-19-2009, 11:37 PM)GileadGarage Really, CC Pressure will somehow limit fuel? I have to think about that one. I know I have some blowby, always have. But it does not seem too bad and I thought it is vented well enough.
Come to think of it, I do smell some vapor after the prob occurs.
Interesting, I'll vent to atm before my drive home
Thanks.
Has anyone ever noticed that oil will fill the tube when revved up with no dipstick???
this should not be happening, it means you have crank pressure - it could easily cut off your fuel supply. You are not breathing well enough. Vent to atm for a trial run or once you notice the problem occurring.
yes. It will actually shut your car down once enough pressure builds. The vac pump exhausts into the timing cavity adding to 'perceived' blowby... somewhat irrelevant, but something to keep in mind as you 'think about this one'...
(07-22-2009, 07:22 PM)totaldisaster yes. It will actually shut your car down once enough pressure builds. The vac pump exhausts into the timing cavity adding to 'perceived' blowby... somewhat irrelevant, but something to keep in mind as you 'think about this one'...
(07-22-2009, 07:22 PM)totaldisaster yes. It will actually shut your car down once enough pressure builds. The vac pump exhausts into the timing cavity adding to 'perceived' blowby... somewhat irrelevant, but something to keep in mind as you 'think about this one'...
sending ccv into the intake does remove pressure by vacuum... I agree. But aren't you going through a catch can first?
I suggested atm to remove that element as a failure / restriction
on the 1980 300sd It was vented directly in to the turbo inlet. oil fumes and all every once and awhile it would build some oil up. and the turbo would suck the oil in to the intake! and the car would accelerate like a bat out of hell leaving rubber into 2nd gear and make the blackest cloud I had ever seen! like in a tractor pull!!!
(07-22-2009, 08:28 PM)totaldisaster sending ccv into the intake does remove vacuum... I agree. But aren't you going through a catch can first?
I suggested atm to remove that element as a failure / restriction
(07-22-2009, 08:28 PM)totaldisaster sending ccv into the intake does remove vacuum... I agree. But aren't you going through a catch can first?
I suggested atm to remove that element as a failure / restriction
3/8 is kinda small... but with it vented to atm I don't believe it would stall your engine ever.
I recently buttoned up all my connections along the boost pathway with tremendous results. I even clocked my compressor housing a tad to get the perfect fit for that intermediate tube from the turbo to the intake mani...
summary: If you ever hear any whistling, you might be losing boost somewhere. Tighten your manifold bolts, inspect the banjo bolt on the intake and the corresponding line... anywhere boost can exit, it will.
It just doesn't make sense for a worn engine to 'suddenly' display performance issues considering the steps you've already taken.
In addition, allowing positive pressure conditions as a normal part of your engine's behavior can effect ring wear primarily because of the way they 'seat' against the cylinder walls during piston travel.
3/8 is much too small. 1/2" should be minimum and I use 3/4" hose on my cars.
High backpressure will also harm the turbo. The engine should have less than 0.1psi positive crankcase pressure or it will affect oil flow out of the turbo.
(07-23-2009, 12:52 AM)ForcedInduction 3/8 is much too small. 1/2" should be minimum and I use 3/4" hose on my cars.
High backpressure will also harm the turbo. The engine should have less than 0.1psi positive crankcase pressure or it will affect oil flow out of the turbo.
(07-23-2009, 12:52 AM)ForcedInduction 3/8 is much too small. 1/2" should be minimum and I use 3/4" hose on my cars.
High backpressure will also harm the turbo. The engine should have less than 0.1psi positive crankcase pressure or it will affect oil flow out of the turbo.
(07-23-2009, 04:55 AM)winmutt(07-23-2009, 12:52 AM)ForcedInduction 3/8 is much too small. 1/2" should be minimum and I use 3/4" hose on my cars.
High backpressure will also harm the turbo. The engine should have less than 0.1psi positive crankcase pressure or it will affect oil flow out of the turbo.
I second that. I have used smaller before and the car is useless.
(07-23-2009, 04:55 AM)winmutt(07-23-2009, 12:52 AM)ForcedInduction 3/8 is much too small. 1/2" should be minimum and I use 3/4" hose on my cars.
High backpressure will also harm the turbo. The engine should have less than 0.1psi positive crankcase pressure or it will affect oil flow out of the turbo.
I second that. I have used smaller before and the car is useless.
So I redid my breather set up, uses the catch can and 5/8 hose vent to atm (down coil spring hole), came out nice. Made a difference! I drove it to work 45 miles w/ AC on and it did not act up, i may have felt it a tiny bit after 75 up a grade, but it was doing well - 70 up the usual hills hanging with "modern" traffic just fine.
I did not push it hard, I'll get on it tonight on the drive home and know for sure whats happening.
I turned the Alda out 1/2 turn. I'm only getting around 9.5-10 psi max but it feels fine - i'm just looking for it to be reliable right now (the new motor will be getting all the tricks though).
I think I'll leave the switchover valve bypassed for now, since the boost is not too high and I have a boost gauge (?). Cruising down the highway at 75 boost is around 6-7psi.
Maybe I can take it on a family trip to CT this weekend afterall.
Thanks again, you guys helped me out a bunch!!!
Yea, it seems to be fixed. runs strong, better then ever on hills. Not sure why all of a sudden the breather was inadequete, maybe because of the new.265's and 26* timing.
Lesson learned about CC ventilation - gotta let them breath!!!
Thanks again
As you advance timing, you increase the top pressures in the cylinder. This leads to greater blowby..
WOW. Great to hear it was solved. Sorry my advice wasn't any help . I would never have thought about CCV. I'll keep all this in mind when I build my catch can tomorrow.
this is great info!
Yea , great info which helped me alot. The car runs perfect, took it on 600 mile trip this weekend all loaded down 80MPH ac cranking, drove like an absolute dream. Great power, no film on the back, virtually no oil leaks either.
The only thing i did notice (completely unrelated) was that the car sat a little bit higher in the back when i got home (noticed that my headlights were pointing down lower) I got under there today and free'd up the swivels on the adj rod and adjusted it a tiny bit, now it sits how i want it. Sure is easier to adj the rear compared to the front! I also changed the SLS fluid again, since I want to protect my functiioning SLS system.
Greasy, glad you didnt take me up on the IP replacement - guess you knew better. Also want to mention that I do still have that 85TD parts car if you are looking for anything.
Thanks again everyone