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: 5,766 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) |
DRPHIL914 |
Jan 24 2015, 12:53 PM
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#2
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Dr. Phil Group: Members Posts: 5,766 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
Last week end I went to try get workingrightthe car, before doing anything I decided to see if it would start at all - started and ran like there was never an issue. So Monday it ran fine and so I finally did the deep tuna can sump and new billet taco plate and sensors replacement with full oil change etc. Drove it the next day ran perfect.
Now those days it was @65-70 degrees. NOW- fast forward to today. I come out this morning , it's 40 degrees out, it barely starts, very rough won't stay running or idle with out feathering the pedal . If I reved it it almost ran smooth and idle for 10 to 15 second then die.. trying to restart it it was like it was flooded - no go. Cranked but no fire. SO I leave to run and the honey do list and garbage run etc. Come back just a few minutes ago. Now its 60 degrees out. --- a friend stops over and I tell him about what's going on with it. So I get in the car to show him how bad it is to get it to start and What the heck? /$^!^#&# It fires right up! Like perfect no skip miss or other issue at all!!!!! I HAVE A CRAZY PSYCHO SPLIT PERSONALITY CAR!!! what are my options here? Won't do any good to test anything else now it's idling perfect as I speak. A/F meter reads 11.5 fuel pressure 29, Either I have a bad cold star valve that floods it out when cold, or ther is a short somewhere that is intermittant. I am befuddled |
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