Fuching DJet issues *SOLVED*, Running out of things to try |
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Fuching DJet issues *SOLVED*, Running out of things to try |
rjames |
Jun 12 2019, 12:19 AM
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#1
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I'm made of metal Group: Members Posts: 3,914 Joined: 24-July 05 From: Shoreline, WA Member No.: 4,467 Region Association: Pacific Northwest |
Last summer all of a sudden my car wouldn’t stay running. If I could get it started the idle would hunt and the car would die unless I kept on the gas. Lack of power at times. All somewhat erratic.
Found that the MPS wouldn’t hold vacuum. Replaced the bad mps with a known good one. Car idles high when cold (higher than I think it should ~1600 rpm) so AAR is good, then when it warms up idle hunts from ~900rpm to the point where it almost dies unless I open the throttle body bleed screw quite a bit and turn the ECU knob just a few clicks away from full clockwise. So I did the following hoping to fix the issue: Replaced all vac hoses including intake runner to plenum hoses. New intakecrunner gaskets Verified plenum isn’t leaking New throttle body gasket Installed NOS throttle body Rebuilt the distributor New condenser Rebuilt injectors and flow tested New fuel lines Fuel pump is less than 2 years old Set timing and dwell with advance disconnected New CHT (resistance reads 1.7 w/engine off @70 degrees in the garage) Calibrated the TPS, even unplugged it to take it out of the equation, didn’t change anything. ECU matches the MPS (both correct part #s for a ‘75 2.0) Tried a known good ECU from a ‘74, no change. Feels like the MPS needs to be calibrated...but then again, these are all the same symptoms I had with the old bad mps. Replacement mps is from a Jeff B and was tested, but I haven’t retested it to see if it’s holding vacuum. (Don’t have the necessary tool, but maybe that’s the next step) Help! What am I missing? |
GregAmy |
Jun 12 2019, 05:23 AM
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#2
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Advanced Member Group: Members Posts: 2,268 Joined: 22-February 13 From: Middletown CT Member No.: 15,565 Region Association: North East States |
Just a note on "known good MPS"...I was having terrible driveability problems with my '74 2L, similar to yours, and tried pretty much everything. Tested the MPS and it held a vacuum. I was stumped.
I was lamenting my probs when the guys at Tangerine said, "rebuild the MPS". "It's holding a vacuum" I replied. "Rebuild the MPS". So I gave them the MPS to rebuild. It transformed the car. Car drives great now. Turns out the diaphragm was cracked (Chris showed it to me) but somehow it was holding a vacuum anyway. Oh well. |
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