Fuel pump bad out of the box? Delphi
#1
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Fuel pump bad out of the box? Delphi
88 4.0 Laredo new engine. After fixing about 100 things and doing Cruiser tips 1,3,4,5,6,7(new)8,9,11,12,13 just now did the FP pump ground, didn't seem to help. it's been running ok with good idle and not rich. Problem was/is, it was lacking power (bogging) under hard acceleration, even tho my pressures measured good. I'm running new Delphi, changed it becauseI did change it the old one was sounding terrible despite measuring ok. So, new Delphi pump and basically the same thing. Btw was pretty disgusted with the quality of the Delphi, I could not get it to sit in the hole right and get the lock ring on so put the new pump in the OE sender bracket and tried to use the new lock ring which was probably cut from a tuna can... that thing was garbage too so used the old one, the new o-ring was HARD not soft like the OE but managed to use it. Anyway, with the resistor in place it's just like the old pump, if I push it it will "lean pop" thru the intake stumble and bog, but if I bypass the resistor it runs much much better with no popping but I can't really get any more than 4k rpm out of it under load- also, with the resistor bypassed the new pump is extremely loud. So this sounds like another lousy FP, or could it be something else? Again, runs much better with the resistor bypassed but still seems to be starving for gas. Should I try another pump, or look elsewhere first? Thanks
#2
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Could it be FPR? Because it's not leaking out the vac port... fuel filter only a few days old, was replaced and the old one didn't seem plugged think the tank is fairly clean.
#3
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Year: 1972 GTO
Model: Cherokee (XJ)
I have to attest to the fit failure of the Delphi fuel pump assy, as I too experienced the exact same problem on a 1988....If the black rubber cone was removed from the return tube then the pump would seat, however then the pump would be unstable in the tank....The only option would have been to install & remove the pump several times to correct the bends in the tubing....In doing so you run the risk of bending the gauge unit, which will lead to another issue of an incorrect reading...So I returned the pump to "Rock Auto" , if by chance you got the pump from "Rock" could it have been my returned pump? I doubt it ...... but at least now its validated that the Delphi pumps have incorrect bends in the tubing.......For the time being I reverted back to a used OE Bosch, but still need to replace it.....Any suggestions ???
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Rastus (06-03-2022)
#4
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Year: 1989
Model: Comanche (MJ)
Engine: 4.0
How many volts are you losing across the ballast resistor? I wonder if it's not bad, or the new pump draws more amperage resulting in a higher voltage drop across the resistor. I think it's a 1.5-ohn resistor.
#5
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Year: 1988
Model: Cherokee (XJ)
Engine: 4.0L
I went through three pumps before I got a good one. The first one moved fuel but there was no signal at all to the fuel gauge. The second one gave great gauge but didn't move any fuel even though it made great pump noises, and the third one did (does) both!
I remember reading, I think from Cruiser, that the RENIX ECM does do a little learning. It seems to me it was in his trove of old service bulletins that RENIX engine may experience some power issues for a number of start n drives. I didn't read that until well after I had put my new engine in, but early on I did experience some popping at WOT that I never did determine the cause, and it went away.
I remember reading, I think from Cruiser, that the RENIX ECM does do a little learning. It seems to me it was in his trove of old service bulletins that RENIX engine may experience some power issues for a number of start n drives. I didn't read that until well after I had put my new engine in, but early on I did experience some popping at WOT that I never did determine the cause, and it went away.
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Rastus (06-03-2022)
#7
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[QUOTE=03Marauderman;3675693]I have to attest to the fit failure of the Delphi fuel pump assy, as I too experienced the exact same problem on a 1988....If the black rubber cone was removed from the return tube then the pump would seat, however then the pump would be unstable in the tank....The only option would have been to install & remove the pump several times to correct the bends in the tubing....In doing so you run the risk of bending the gauge unit, which will lead to another issue of an incorrect reading...So I returned the pump to "Rock Auto" , if by chance you got the pump from "Rock" could it have been my returned pump? I doubt it ...... but at least now its validated that the Delphi pumps have incorrect bends in the tubing.......For the time being I reverted back to a used OE Bosch, but still need to replace it.....Any suggestions ???[/QUOTE
Ha, no it was an AZ unit and if I determine that the first one was a faulty new pump I'm going to cobble it back together cut wires and all, put it in a plastic bag and return it. Interesting note, just picked up a Delphi pump (pump only) and it's a different pump from the one that came in the assembly... anyway fingers crossed eh.
Ha, no it was an AZ unit and if I determine that the first one was a faulty new pump I'm going to cobble it back together cut wires and all, put it in a plastic bag and return it. Interesting note, just picked up a Delphi pump (pump only) and it's a different pump from the one that came in the assembly... anyway fingers crossed eh.
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#8
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I went through three pumps before I got a good one. The first one moved fuel but there was no signal at all to the fuel gauge. The second one gave great gauge but didn't move any fuel even though it made great pump noises, and the third one did (does) both!
I remember reading, I think from Cruiser, that the RENIX ECM does do a little learning. It seems to me it was in his trove of old service bulletins that RENIX engine may experience some power issues for a number of start n drives. I didn't read that until well after I had put my new engine in, but early on I did experience some popping at WOT that I never did determine the cause, and it went away.
I remember reading, I think from Cruiser, that the RENIX ECM does do a little learning. It seems to me it was in his trove of old service bulletins that RENIX engine may experience some power issues for a number of start n drives. I didn't read that until well after I had put my new engine in, but early on I did experience some popping at WOT that I never did determine the cause, and it went away.
#9
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Thread Starter
I do not know, thought about it but haven't checked that yet since running much much better with it bypassed made me think it was just another bad pump. Have another... gonna give it a whirl- getting real quick at taking these out now.
#10
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Man you have got to be kidding me. This "replacement" pump is like 3" shorter than the one that comes with the new assembly, no instructions ("install hardware"), couple of rinky-dink spacers that aren't big enough to fill the gap... how, can they pass this crap off on us? I can make it work but geeee-whiz.
#11
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- ★★2 out of 5 stars.
· 10 months agoFuel Pump
This one is a smaller size than the one in the vehicle, need to return this fuel pump. Tony
- What kind of vehicle do you drive?
- 1991 Jeep Cherokee 4.0
Recommends this product
✘ NoHelpful?
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Report Evan
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★1 out of 5 stars.
· 2 years agoDid Not Even Remotely Fit My Vehicle.
Disliked the compatibility with my vehicle. Does not fit a 1989 jeep Comanche 4.0
- What kind of vehicle do you drive?
- 1997 Ford e350
Recommends this product
✘ No
#12
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Year: 1972 GTO
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Love rants...excellent way to vent out frustrations...been there many times.....You really have to wonder ...I get that Bosch no longer makes the correct fuel pump (in size & dimension) as the OE, but the so called replacements look like Rube Goldberg applications that would be used in Cuba....a 'fits all pump" with a bunch of rubber donuts that don't fit anyway, with cut & splice hardware.....Kinda sad in todays technology world that I had to go to my donor XJ & pull out the OE fuel pump, with my fingers crossed hoping that it would work....How there are so many issues with a simple electric fuel pump simply amazes me....Like trying to fit a round peg in a square hole.....
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Rastus (06-04-2022)
#14
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[QUOTE=dmoe69;3675702]I went through three pumps before I got a good one. The first one moved fuel but there was no signal at all to the fuel gauge. The second one gave great gauge but didn't move any fuel even though it made great pump noises, and the third one did (does) both!
Unreal, after futzing around to get it to fit, zero pressure, emoji's do not suffice. My gauge reads fine because it's the original sender.
Unreal, after futzing around to get it to fit, zero pressure, emoji's do not suffice. My gauge reads fine because it's the original sender.