Low fuel primary pressure or too lean mixture setting.
since the fuel metering unit was rebuilt, the base mixture setting (which is purely mechanical) may need to be reset.
Posts: 301
My VIN: 02855
Club(s): (NCDMC) (DCUK)
Low fuel primary pressure or too lean mixture setting.
since the fuel metering unit was rebuilt, the base mixture setting (which is purely mechanical) may need to be reset.
Location: IL
Posts: 44
Location: Northern NJ
Posts: 8,570
My VIN: 10757 1st place Concourse 1998
If someone turned the mixture screw, then all that might be necessary is to properly adjust it. If the mixture unit was taken all apart it is possible that adjustment was disturbed. Same for the Primary Pressure Regulator. One of the "O" rings inside could have been damaged or the correct # of shims was not assembled. Again, is the frequency valve buzzing? If it isn't, then that would be the first thing I would work on. If it doesn't buzz, you can't "adjust" your way out of this.
David Teitelbaum
Location: IL
Posts: 44
Yes the frequency valve was buzzing. What is circled in blue was buzzing.
Is what is circled in yellow where the adjustment for fuel mixture is?
936A82AA-4F8C-4D2F-9E14-F8188F4E0E49.jpg5C716ECC-5C96-47C5-994A-2EDA9B6ED81C.jpg
Last edited by JSzabo; 01-25-2021 at 08:51 PM.
Location: Northern NJ
Posts: 8,570
My VIN: 10757 1st place Concourse 1998
You are correct on both. Now I would check the injectors to make sure they are flowing equally and each has a good pattern and the seals are not hard, letting air leak.
David Teitelbaum
Posts: 301
My VIN: 02855
Club(s): (NCDMC) (DCUK)
Location: Reedsburg, WI
Posts: 4,026
My VIN: 5180
Club(s): (DMWC) (DCUK)
Did, you remove the idle air brass pipe the enters the lower metering housing? If yes make sure the tube is actually inserted in the housing hole. It’s easy to think it was inserted put in reality the tube slid below or beside the port opening. This would be a massive unmetered air leak, causing a very lean condition. The air plate would not move down allowing the fuel pressure to increase and open the injectors. This may explain why you were able to get it to stay running by manual pressing down on the air plate. Did you work the throttle linkage spool by hand when you were doing this?
DENNIS
VIN 5180, Frame 3652, STAGE II, DM-eng Solid State Solutions (RPM Rly, Dm.Lt.Mod., Fan Fail Mod. , FAN Rly, HS.Rly) , HID headlights, SPAX user since 2009, Eibach springs, M Adj. Rear LCA's, DPNW poly-sway bar kit, DMCEU LCA Stabilizer link kit, DMCMW Illuminated door sills, Aussie Illuminated SS Shifter plate, REAL MOMO EVO Steering wheel, DELOREANA Extended View Side Mirrors w/ Heaters, DELOREANA LED Door Lights.
Location: IL
Posts: 44
I will have to get into that later on the weekend when I have my Brother-in-law and Mechanic available.
Thanks I won’t touch unless needed too. It looks like something is in the hole. Is that a factory “plug”?
Yes we did remove the bigger brass pipe under the fuel mixture housing/fuel injection. I didn’t separate the KJet system DMC of Midwest did the separation and reconnection. We will have to check and see to make sure but I believe we put the pipe back in the right spot. Could it have something to do with the o-ring that that pipe goes into? I’m going to have to ask about the throttle linkage. I was in the car starting it.
This video is, of the sounds the car makes after it starting, then dying.
Last edited by JSzabo; 01-25-2021 at 11:16 PM.
Location: IL
Posts: 44
Does anyone have a video of anyone drilling out or how to remove the CO plug? I’m trying to see how to do it with out taking off the whole Kurt system.
Posts: 1,235
This thread is interesting because your symptoms are exactly what mine were after cleaning the fuel tank, lines and filter. To be clear, mine would run for a few seconds after releasing the key. Someone suggested mine was running on the start system. I believe this to be true. After pulling my PPV and distroying the O-ring accidently , now I have differnt symptoms. Now mine runs if I rev the engine, but won't idle. I'm currently waiting for new parts.
My theory, the PPV was stuck at a low pressure setting that was below the pressure to spray from the injectors. So it would start on the start system and shut down as soon as it switched to the primary injectors. After I screwed the PPV, it allowed to much pressure on the primary system. So the injectors spray all the time. If I rev the engine, it will run, but if I let it idle, it floods out. I'm hoping the new O-rings will fix it. I should know in a few days.
Please up date this thread if you sort it out.