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Engine/Transmission (1998.5 - 2002) Too much fuel pressure

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Can too much fuel pressure from pusher pump to injector pump cause it not to start? I put new carter pump on truck and after bleeding injector pump and injectors (it still wont start) it buries my fuel pressure gauge (hooked to schrader port). Dont know if I need a pressure regulator or I'm just spitting in the wind. This has been a very aggrevating time with my truck that has performed flawlessly for 11 years and now for almost 3 months has sat in my driveway while I try to get it to run. Replaced fuel tank sending unit, pusher pump and injector pump and it still wont start. I did get a 1694 code the last time I tried. I'm at wits end and hope someone can assist me
 
My recollection of my 2nd gen days is that anything over 20 psig can cause hard starting. Some trucks can tolerate a bit more, but some are hard starting at 20 psig. I'm not sure why a stock Carter pump (the pump you're referring to IS the stock Carter lift pump, right??) would generate that kind of pressure unless the bypass on the VP-44 wasn't working.



Rusty
 
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You might try removing the overflow valve on the injection pump fuel return line. Take a blow gun and blow air through the end of the banjo bolt. (the valve is inside the bolt) The ball should push down and let air come out the cross drilled holes. See page 14-84 in the factory service manual. If this checks good blow out the return fuel line with the fuel cap off with someone listening for the air inside the fuel tank.
 
Yes, too much pressure at the IP will cause hard starts. There is a flash for the ECM to only run the LP for 10 seconds or so at start to just prime the line but not hold pressure. The pressure holds something in the pump closed so it won't let fuel into the pumping chamber and it gets worse as the pump gets older.
 
Ive tried everything and it still doesn't start. Called Dodge dealer in Hagerstown and am having it towed on Tue for them to troubleshoot. Costly tow bill and troubleshoot fee but dont see any other way. As a follow-up I just went out and tried it again and got a P0102 (tps) code. This is the first time in months of trying to start it that this code had come up. What gives?
 
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What about trying this:
1) raise hood and remove plastic cover on Schrader fitting on injection pump inlet
2) bump starter and to run lift fuel pump - leave key on
3) immediately get out and verify that you are getting fuel pressure by depressing Schrader valve on injection pump inlet while the pump is running.
4) if fuel sprays out wait for pump to stop
5) hit Schrader one more time to verify no pressure
6) return to cab and run starter while pumping accelerator without turning key back off.
 
As a follow-up I just went out and tried it again and got a P0102 (tps) code.

If you are pumping the accelerator it will throw this code, make sure you reset the APPS and don't pump the accelerator when trying to start. You should never have to touch the accelerator to start a drive-by-wire engine.

If you still get the code it could be the APPS has gone bad or the connection is bad. Try reseating it, disconnect the batteries and tie the ground cables t gether for 30 minutes to reset all the electronics.
 
Well here it is. After replacing fuel tank sending unit, pusher pump and injector pump, checking all wiring, etc. bleeding injectors no less than 15 times----it was my ECM that had gone south for the winter. New ECM and truck runs like a champ.
 
Well here it is. After replacing fuel tank sending unit, pusher pump and injector pump, checking all wiring, etc. bleeding injectors no less than 15 times----it was my ECM that had gone south for the winter. New ECM and truck runs like a champ.



GOOD JOB! Glad you got her back on the road.



I'm assuming this was discovered after the tow job to the dealership?
 
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