D_jet trouble shooting question - car is home, journey continues, June, update- no more problem-- the fix was simple.... |
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D_jet trouble shooting question - car is home, journey continues, June, update- no more problem-- the fix was simple.... |
DRPHIL914 |
Dec 15 2014, 12:39 PM
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#1
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Dr. Phil Group: Members Posts: 5,767 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
OK. car has been in shop for the past week, and today Bob spent several hours on it but what he found was when the MPS is disconnected from the vac hose it will idle and run, but when it gets connected it goes immediately lean and dies, and will not run with that hose on there- the MPS holds Vac no loss of pressure, but that doesnt mean that its not bad.
1- i thought that if an MPS went bad it defaulted rich? but when this is getting vac it goes lean right away and dies. but it will run and idle with out the vac , the AF meter then shows 9.8-10.2 or so which is of course rich but not flooding out. so the question is why is it going lean when hooked up? when this issue started about 2 weeks ago, it had been running just fine and all of a sudden it quit running. 2. could there be another issue we dont see that would be making it way to lean other than the MPS? might need to test another MPS, my 2nd one i just bought from someone here and it has never been opened but will not hold vac (slowly looses vac pressure) so it probably need to be opened and re-sealed. not a good candidate to trouble shoot with. ------ FYI- 1975 d-jet 2.0. newer wiring harness , CHT is newish(replaced 2 months before this issue started and was running perfect at that time) |
cary |
Feb 11 2015, 08:23 AM
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#2
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Advanced Member Group: Members Posts: 3,900 Joined: 26-January 04 From: Sherwood Oregon Member No.: 1,608 Region Association: Pacific Northwest |
Did a quick read.
I'd disconnect the cold start injector, both fuel and electrical. I haven't run one in years, even in Montana. If it hasn't been suggested or done. I'd also suggest getting new harnesses in the engine compartment. Forty years is a lot of heat cycles. Especially on an air cooled car. |
DRPHIL914 |
Feb 11 2015, 12:40 PM
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#3
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Dr. Phil Group: Members Posts: 5,767 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
Did a quick read. I'd disconnect the cold start injector, both fuel and electrical. I haven't run one in years, even in Montana. If it hasn't been suggested or done. I'd also suggest getting new harnesses in the engine compartment. Forty years is a lot of heat cycles. Especially on an air cooled car. thanks for the comments- i agree about the cold start injector- it really acted like it was flooded out those couple times it wouldnt start, so i might do that. The FI harness was replaced a couple years ago, new from Jeff Bowlsby. and just to make sure my mechanic went thru every circuit on it to double check that there were no shorts and each one check out correctly according to anders and what the ohm readings should be etc. i think that cold start injector is the only thing i have not touched since this started- and to complicate issues, at some point the MSP was going as well but that has been sorted and the one i have in there now is right on where i want it. Supposed to be really chilly saturday morning ( @40 degrees) but i'm still planning on going to the cars n coffee -- (IMG:style_emoticons/default/driving.gif) |
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