Suspect bad fuel pump 2006 Express 3599 6.0L
April 1st, 2017, 7:42 PM
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Suspect bad fuel pump 2006 Express 3599 6.0L
Van has never had starting problems... It sat about a week and then crank but no start.
I had never paid attention to the sound of the fuel pump before. That was one of the first things I wondered about. When you turn the key to run..there is a "clunk" in the gas tank. I don't hear any whirring. When I opened the gas cap..there was no pressure.
I figured I would be a genius and continue troubleshooting. Without knowing it...I left the key in run..while I swapped relays and pulled fuses. Anyway..the relay for the fuel pump works. I beep the horn..pull that relay and put in fuel pump spot and put fuel pump relay in horn spot...horn still works. With no relay..horn doesn't work.
Now for the weird thing. With the relay out for the fuel pump...the "clunk" sound still happens. That's weird...but maybe the clunk is from something else. Again...no "whirring noises".
I checked the fuse marked fuel pump. Looked great. Replaced it anyway. Same.
The van starts and runs on starting fluid. So...I'm assuming that takes care of spark. I have noid lights...BUT HAVE NOT plugged them in yet. I assumed since it starts on starting fluid.. Should I still try NOID light test??
Luckily van is just above empty. Right above red on the gauge. I've run it way low before..so I'm assuming there is enough gas. The fuel low light WAS NOT on before I shut down last time it ran.
Codes. I had been having problems with heated O2 circuits. Replaced the sensors and code remained. So..I quit worrying about it. While checking fuses this time...I happened to check one labled O2 sensor and it was burned out. Replaced it..cleared codes and codes stay off...although the engine has only run on starting fluid since then.
OK...my weird code.
P1626 theft deterrent start enable signal not received. That was present AFTER I changed the fuse for the O2 sensor. I had not checked codes in several weeks. I'm curious if my messing around with relays with the key to run triggered this.
My keys DO NOT have chips in them. I've gotten $3 keys and lows that works just fine. Never seen my security light on.
This code cleared..and has not come back. Although quick research on the internet says this can cause no starts...I haven't figured out how to check it and fix it. Plus...it hasn't come back.
Basically..want to troubleshoot as much as I can before I drop the tank. I've dropped other gm tanks and changed pumps...just never on a van. Luckily not much gas in there.
Thoughts??? Am I missing anything??
NH
I had never paid attention to the sound of the fuel pump before. That was one of the first things I wondered about. When you turn the key to run..there is a "clunk" in the gas tank. I don't hear any whirring. When I opened the gas cap..there was no pressure.
I figured I would be a genius and continue troubleshooting. Without knowing it...I left the key in run..while I swapped relays and pulled fuses. Anyway..the relay for the fuel pump works. I beep the horn..pull that relay and put in fuel pump spot and put fuel pump relay in horn spot...horn still works. With no relay..horn doesn't work.
Now for the weird thing. With the relay out for the fuel pump...the "clunk" sound still happens. That's weird...but maybe the clunk is from something else. Again...no "whirring noises".
I checked the fuse marked fuel pump. Looked great. Replaced it anyway. Same.
The van starts and runs on starting fluid. So...I'm assuming that takes care of spark. I have noid lights...BUT HAVE NOT plugged them in yet. I assumed since it starts on starting fluid.. Should I still try NOID light test??
Luckily van is just above empty. Right above red on the gauge. I've run it way low before..so I'm assuming there is enough gas. The fuel low light WAS NOT on before I shut down last time it ran.
Codes. I had been having problems with heated O2 circuits. Replaced the sensors and code remained. So..I quit worrying about it. While checking fuses this time...I happened to check one labled O2 sensor and it was burned out. Replaced it..cleared codes and codes stay off...although the engine has only run on starting fluid since then.
OK...my weird code.
P1626 theft deterrent start enable signal not received. That was present AFTER I changed the fuse for the O2 sensor. I had not checked codes in several weeks. I'm curious if my messing around with relays with the key to run triggered this.
My keys DO NOT have chips in them. I've gotten $3 keys and lows that works just fine. Never seen my security light on.
This code cleared..and has not come back. Although quick research on the internet says this can cause no starts...I haven't figured out how to check it and fix it. Plus...it hasn't come back.
Basically..want to troubleshoot as much as I can before I drop the tank. I've dropped other gm tanks and changed pumps...just never on a van. Luckily not much gas in there.
Thoughts??? Am I missing anything??
NH
April 2nd, 2017, 5:20 PM
#2
Remove passenger seat, remove passenger knee panel, then remove doghouse. You'll see a schrader valve on the fuel rail, check to see if there is fuel pressure. Ideally you want the fuel pump tester on it ($30 at harbor freight).
Dropping the tank is easy, it's just two 15mm bolts holding the straps and it falls down, but reinstalling is more pain. So before you do this - have someone turn the key on, while you're under the van putting your ear to the bottom of gas tank. You will very clearly be able to hear whether the pump comes to life.
Dropping the tank is easy, it's just two 15mm bolts holding the straps and it falls down, but reinstalling is more pain. So before you do this - have someone turn the key on, while you're under the van putting your ear to the bottom of gas tank. You will very clearly be able to hear whether the pump comes to life.
April 10th, 2017, 11:06 AM
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It was the fuel pump....and as predicted...getting it all back together and installed was worse than getting it out. \
Things I did before ordering the pump and dropping the tank. I took the relay to NAPA and a guy there explained the diagram to me. I used a test light to check for power at pin 30 (there was power), so I made a jumper to go from 30 to pin 87. For good measure I put the test light down in 87 with the jumper and verified power.
After a long time of the jumper in (and really not hearing any noise from the tank) I tried to start it again and it coughed a couple times but wouldn't start. I'm assuming the pump was barely working.
Not sure if I'm allowed to link to outside sources (mods...sorry if I'm not supposed to).
Based on price and lifetime warranty I decided to give 1 A Auto.com a try.
https://www.1aauto.com/electric-fuel...1096673&y=2006
$108 for the unit was far better than I could find anywhere else. The pump showed up quickly and worked at advertised. It was a little tight fitting down in the tank, but I got it in there after rotating it back and forth some for 5 minutes or so. Most of the internet videos show it dropping right in.
I used to jacks and two teenage helpers to get the gas tank back in place. No real advice here other than go slow and lots of little adjustments.
Anyway...I'm assuming that my old one was original. Van has 200k on it now. I've had it since about 95k miles. Hopefully will never have to do that again.
Thanks for the assist.
NH
Things I did before ordering the pump and dropping the tank. I took the relay to NAPA and a guy there explained the diagram to me. I used a test light to check for power at pin 30 (there was power), so I made a jumper to go from 30 to pin 87. For good measure I put the test light down in 87 with the jumper and verified power.
After a long time of the jumper in (and really not hearing any noise from the tank) I tried to start it again and it coughed a couple times but wouldn't start. I'm assuming the pump was barely working.
Not sure if I'm allowed to link to outside sources (mods...sorry if I'm not supposed to).
Based on price and lifetime warranty I decided to give 1 A Auto.com a try.
https://www.1aauto.com/electric-fuel...1096673&y=2006
$108 for the unit was far better than I could find anywhere else. The pump showed up quickly and worked at advertised. It was a little tight fitting down in the tank, but I got it in there after rotating it back and forth some for 5 minutes or so. Most of the internet videos show it dropping right in.
I used to jacks and two teenage helpers to get the gas tank back in place. No real advice here other than go slow and lots of little adjustments.
Anyway...I'm assuming that my old one was original. Van has 200k on it now. I've had it since about 95k miles. Hopefully will never have to do that again.
Thanks for the assist.
NH