Car never ran better - THEN!, Seems when hot there is no low end power |
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Car never ran better - THEN!, Seems when hot there is no low end power |
ctc911ctc |
Jun 25 2023, 04:30 PM
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#1
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Senior Member Group: Members Posts: 893 Joined: 9-June 18 From: boston Member No.: 22,206 Region Association: North East States |
'74 2.0 - 25K miles
It has been a very long journey. I, with my 17yr old son who is now 21, rebuilt nearly every system including the Engine and Transmission (a nod to Dr. Evil !! ). My son and I have learned a great deal, however, this one has me stumped. The car runs terrific and is strong, smooth and a joy to drive, today I took it around the Lakes here in Arlington MA and at the end of the drive there is a hill with a red light - I caught the red. I waited as the button pushers jaywalked (after they hit the button) and then I waited some more with the crosswalk signs blinking and no one crossing.....sigh OK, there is the green and I ease out the clutch and apply a little gas AND nothing...... nearly idling. I then bury the gas and the car stalls.......and since this is New England everyone starts beeping and yelling - so I get the flashers on and people go around me. I wait another light cycle and get the cars started by pumping the gas and keeping it running over 1500, once it started moving it ran fine. It is almost as if there was zero power below 1500, though when the car was rolling everything worked as you would expect. When the car is cold the low power is as normal as a 90HP engine can be. The temp of the car is about 2/3rds deflection of the center console temp gauge. I am thinking all sorts of complicated thoughts.......head temp sensor is sending weird signals to the Bosch controller OR when super hot the vacuum system starts leaking, etc. So, I thought I would start here - any ideas teeners???? Keep me sane and guide me to the light! CTC911CTC |
r_towle |
Jul 2 2023, 09:27 AM
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#2
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Custom Member Group: Members Posts: 24,586 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
That is an aftermarket 2 port pump for a 75
While I don’t agree, the filter goes after the pump on the FI side of the loop. There is no filter (aside from the tank sock) before the pump. Start by swapping that, and move the filter further away from the heat source, that is a place for fuel to accumulate and boil….get it out of the line of fire. See if you can find some pictures of the original placement of the pump. It should be up in the corner above the heater hose. Again, this location takes it out of the line of fire from the flapper box exhaust. Lastly, make sure you have not swapped the hoses around from tank to pump. The feed hose that goes to the pump has no stub pipe on it, just the sock ( inside the tank) and thus can suck fuel at weird angles and until the tank is empty. The return pipe has a 1/2- 3/4 inch piece stick into the tank, so it won’t suck fuel at weird angles or when close to empty. |
ctc911ctc |
Jul 2 2023, 04:04 PM
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#3
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Senior Member Group: Members Posts: 893 Joined: 9-June 18 From: boston Member No.: 22,206 Region Association: North East States |
Rich,
Good to exchange notes with you today, I rebuilt the tank - it is in these pages somewhere - and recall getting the two sorted, one is the return the other the supply. I believe I have it correct - is there an easy way to tell? I have the Stainless steel replacement fuel lines, purchased the 9.5mm from Tangerine. Thank you Rich! That is an aftermarket 2 port pump for a 75 While I don’t agree, the filter goes after the pump on the FI side of the loop. There is no filter (aside from the tank sock) before the pump. Start by swapping that, and move the filter further away from the heat source, that is a place for fuel to accumulate and boil….get it out of the line of fire. See if you can find some pictures of the original placement of the pump. It should be up in the corner above the heater hose. Again, this location takes it out of the line of fire from the flapper box exhaust. Lastly, make sure you have not swapped the hoses around from tank to pump. The feed hose that goes to the pump has no stub pipe on it, just the sock ( inside the tank) and thus can suck fuel at weird angles and until the tank is empty. The return pipe has a 1/2- 3/4 inch piece stick into the tank, so it won’t suck fuel at weird angles or when close to empty. |
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