replaced intake gasket . . now no fuel pressure
#12
Re-check your grounds. The only ground I removed during my plenum gasket was the one by the power steering pump. Make sure both cables are hooked on that stud. Also verify that the three plugs in the pcm are seated correctly if you messed with that. If you messed with anything additional that normally wasn't done during the gasket replacement process, look there.
#13
#14
Clean every ground you see and re-attach, best thing I can tell ya. Disconnect your battery first lol.
Last edited by pcfixerpro; 08-12-2010 at 01:01 PM.
#17
Ive been all over this thing . . . I was underneath looking up at the back of the intake. I could see the wires, everything looks good. Its driving me crazy. I did this for free, for a friend . . .uuuggg. So the bottom line is I lost the fuel pump, fuel gauge and even a connection to the computer testing for codes from the OBDII port. I cannot say for sure the port problem wasn't there. But I do know tyhe fuel gauged worked and of course it had fuel pressure I'ml ooking for a "connection" between those two. I seem to have power at the relays when I check them . . I'm lost now.
#18
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I want you to run a simple test to see if you've got voltage to the COIL.
IF you have a DMM:
DMM TEST PROCEDURE: MEASURE VOLTAGE TO COIL
Set the DMM to measure DC voltage.
Using the RED PROBE, wrap a paper clip around the RED probe and insert it into the underside of the connector at the primary side / input side of the coil. Make sure this DOES NOT SHORT TO GROUND- otherwise, there's going to be a major problem later.
GROUND the BLK probe to the HEADLIGHT GROUND at chassis.
Measure the DC voltage coming into the COIL at KEY <ON>
It should be ~ 12 VDC
TEST PROCEDURE: NO DMM
Remove the coil wire from the coil. Turn it over for ONE SEC MAX. NOTE ARC TO GROUND off COIL secondary.
<IF> NO SPARK IS SEEN: you may have a failsafe condition to which, either the CKPS or CPS is not connected OR, it's SHORTED to GND. It's also possible that it's something else.
<IF> spark is witnessed, then, we've got to look elsewhere.
NEXT TEST: FUEL PUMP MOTOR VERIFICATION
Have someone turn the KEY <ON>
While lying near the fuel tank, listen for the FUEL PUMP to engage and startup. NOTE: this will last for 3 seconds in duration and automatically shut off if the vehicle is not running. It's a failsafe mechanism.
<IF> you DO NOT HEAR the FUEL PUMP start up- chances are, there's no supply and, a failsafe event has been triggered.
<IF> you DO HEAR the FUEL PUMP start up, then, it's not a SUPPLY ISSUE.
Revisit the rear of the intake.
Look on the right side of the dizzy.
Look for TWO black connectors (use a good light)
VERIFY that both are connected.
<IF> one or more is disconnected, this is your root problem.
<IF> one is PINCHED under the intake, at the rear, it will KILL / CUT power to the EFI system AND the cluster.
WHY or HOW does this happen? When and if the wire becomes pinched, it will short to ground this 5-volt sensor supply.
The END RESULT:AUTO SHUT DOWN the PCM as well as creating a NO BUS condition.
Check your CKPS (Crank Position Sensor) harness for SHORT to GND condition.
CHECK the CPS for this as well. I run all my sensor wires BEHIND the dizzy to prevent that from happening at the time of working at the intake level BUT, OTHERS, run the wires IN FRONT of the dizzy thus, making it totally possible for these wires to become trapped under neath at time of install thus SHORTING THEM TO GROUND.
This just happened recently to another Dodge Forum poster who worked on his intake and, I helped him solve it by asking him to revisit the rear of the intake. Sure enough, it was not connected.
Start there and report back.
CM
IF you have a DMM:
DMM TEST PROCEDURE: MEASURE VOLTAGE TO COIL
Set the DMM to measure DC voltage.
Using the RED PROBE, wrap a paper clip around the RED probe and insert it into the underside of the connector at the primary side / input side of the coil. Make sure this DOES NOT SHORT TO GROUND- otherwise, there's going to be a major problem later.
GROUND the BLK probe to the HEADLIGHT GROUND at chassis.
Measure the DC voltage coming into the COIL at KEY <ON>
It should be ~ 12 VDC
TEST PROCEDURE: NO DMM
Remove the coil wire from the coil. Turn it over for ONE SEC MAX. NOTE ARC TO GROUND off COIL secondary.
<IF> NO SPARK IS SEEN: you may have a failsafe condition to which, either the CKPS or CPS is not connected OR, it's SHORTED to GND. It's also possible that it's something else.
<IF> spark is witnessed, then, we've got to look elsewhere.
NEXT TEST: FUEL PUMP MOTOR VERIFICATION
Have someone turn the KEY <ON>
While lying near the fuel tank, listen for the FUEL PUMP to engage and startup. NOTE: this will last for 3 seconds in duration and automatically shut off if the vehicle is not running. It's a failsafe mechanism.
<IF> you DO NOT HEAR the FUEL PUMP start up- chances are, there's no supply and, a failsafe event has been triggered.
<IF> you DO HEAR the FUEL PUMP start up, then, it's not a SUPPLY ISSUE.
Revisit the rear of the intake.
Look on the right side of the dizzy.
Look for TWO black connectors (use a good light)
VERIFY that both are connected.
<IF> one or more is disconnected, this is your root problem.
<IF> one is PINCHED under the intake, at the rear, it will KILL / CUT power to the EFI system AND the cluster.
WHY or HOW does this happen? When and if the wire becomes pinched, it will short to ground this 5-volt sensor supply.
The END RESULT:AUTO SHUT DOWN the PCM as well as creating a NO BUS condition.
Check your CKPS (Crank Position Sensor) harness for SHORT to GND condition.
CHECK the CPS for this as well. I run all my sensor wires BEHIND the dizzy to prevent that from happening at the time of working at the intake level BUT, OTHERS, run the wires IN FRONT of the dizzy thus, making it totally possible for these wires to become trapped under neath at time of install thus SHORTING THEM TO GROUND.
This just happened recently to another Dodge Forum poster who worked on his intake and, I helped him solve it by asking him to revisit the rear of the intake. Sure enough, it was not connected.
Start there and report back.
CM
Last edited by cmckenna; 08-12-2010 at 08:38 PM.
#19
CM . . not that this helps . . but I am an experienced automotive person, just not with these vehicles. This is my first time working with Dodge truck. So upgrade my thoughts and what I have done a bit over the standard DIYer. I really appreciate your help. It helps to have some experienced with this engines to be able to run through common mistakes. I preach and teach KISS. Most times it works. I cannot figure anything I have done wrong. I would be happy to admit I did something, but have found nothing. I see the tall crank sensor on the back of the block. I did not disconnect that wire, no need to to remove the intake. The only other wire I see on the back goes to the dizzy, perhaps that is where the can sensor is on these engines? I do not have power going to the fuel pump. It is quiet. I have about 1/2 tank of fuel according to the owner and even put a couple gallons in to make sure But the gauge does not budge. I have not checked for voltage at the coil. I will do that momentarily and get back to you. In checking the crank sensor harness . . any specific wire to check or just make sure known have continuity to ground??
#20
Do as cmckenna suggests,
Check cam position sensor (pick up sensor, in distributor), make sure it is plugged into the wiring harness and verify wire is not pinched in the manifold.
Verify crank position sensor is plugged into the wiring harness and the cord is not pinched in the intake manifold.
If you removed the fuel system relay, verify you plugged it back into the correct port and not a blank in the PDC.
TPS will not cause this error, or IAC motor, coolant temp sensor, either A/C connection, alternator connection, or IAT. Never ran a truck without the MAP sensor hooked up, so IDK about that one.
Check that you plugging in the coil if you unplugged it.
Check that the coil wire got put on the correct terminal on the disty. Shouldn't cause this issue, but hey.
Make sure all your injector plugs are plugged into the correct injector. It should still fuel up but I don't know if the PCM auto shuts off if it knows it's plugged into the wrong firing order.
Make sure you reconnected the gas line and you aren't spraying gas everywhere, J/K.
It's also possible you had a short that blew a fuse/relay. Might have to check fuses in the PDC to verify that something didn't accidentally short and blow. You can also swap the fuel system relay with another non-essential relay of the same AMP rating to see if the fuel pump starts to work.
Check cam position sensor (pick up sensor, in distributor), make sure it is plugged into the wiring harness and verify wire is not pinched in the manifold.
Verify crank position sensor is plugged into the wiring harness and the cord is not pinched in the intake manifold.
If you removed the fuel system relay, verify you plugged it back into the correct port and not a blank in the PDC.
TPS will not cause this error, or IAC motor, coolant temp sensor, either A/C connection, alternator connection, or IAT. Never ran a truck without the MAP sensor hooked up, so IDK about that one.
Check that you plugging in the coil if you unplugged it.
Check that the coil wire got put on the correct terminal on the disty. Shouldn't cause this issue, but hey.
Make sure all your injector plugs are plugged into the correct injector. It should still fuel up but I don't know if the PCM auto shuts off if it knows it's plugged into the wrong firing order.
Make sure you reconnected the gas line and you aren't spraying gas everywhere, J/K.
It's also possible you had a short that blew a fuse/relay. Might have to check fuses in the PDC to verify that something didn't accidentally short and blow. You can also swap the fuel system relay with another non-essential relay of the same AMP rating to see if the fuel pump starts to work.