Interesting lift pump situation
#1
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Interesting lift pump situation
Today I stopped at the auto parts stor to get a part for my street rod.
When I came out it was hotter than blazes and I wiped my brow. (fingers now damp). When I attempted to start the truck my fingers slipped off the key/switch before the motor started. It barely turned over. Then when I went to try to restart it wouldn't start. It sounded like it was firing on one cylinder but not enough to start.
Well the lift pump pressure was down to 0 so I thought ..great lift pump failed right in the parking lot of the auto parts store. I have a new spare under the rear seat. I still use the stock one...170k on this one. Unfortunately it was the middle of the after noon ...hottest part of the day and I had just driven 50 miles on the highway so the truck was hot.
I tried bumping the starter several times but the LP was still dead. Then I pulled out the Smarty to check codes. PO 1682 which is a low voltage probably from when I replaced a failed alternator a while ago but no lift pump or fuel codes. ????
So I opened the hood to take a look at what I was going to need for tools. The LP to mount nuts are really tough when the motor is hot. Well dreading a scorching afternoon I though I better try bumping the starter one more time. Zowwie...the lift pump is running and 13-14 psi just like new. I then cranked the motor and it started right up just like it always does (fine CTD) Man I was happy.
So I had 5-6 other stops and it worked just fine. WOT is still right at 8-9 cruise is 13. No change at all.
So what did I do by missing the start sequence??? I've never heard of this before.
When I came out it was hotter than blazes and I wiped my brow. (fingers now damp). When I attempted to start the truck my fingers slipped off the key/switch before the motor started. It barely turned over. Then when I went to try to restart it wouldn't start. It sounded like it was firing on one cylinder but not enough to start.
Well the lift pump pressure was down to 0 so I thought ..great lift pump failed right in the parking lot of the auto parts store. I have a new spare under the rear seat. I still use the stock one...170k on this one. Unfortunately it was the middle of the after noon ...hottest part of the day and I had just driven 50 miles on the highway so the truck was hot.
I tried bumping the starter several times but the LP was still dead. Then I pulled out the Smarty to check codes. PO 1682 which is a low voltage probably from when I replaced a failed alternator a while ago but no lift pump or fuel codes. ????
So I opened the hood to take a look at what I was going to need for tools. The LP to mount nuts are really tough when the motor is hot. Well dreading a scorching afternoon I though I better try bumping the starter one more time. Zowwie...the lift pump is running and 13-14 psi just like new. I then cranked the motor and it started right up just like it always does (fine CTD) Man I was happy.
So I had 5-6 other stops and it worked just fine. WOT is still right at 8-9 cruise is 13. No change at all.
So what did I do by missing the start sequence??? I've never heard of this before.
#2
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I have no answer for your question but I have had my rig do the same thing with the lift pump when I just bumped the starter and didn't get it to do the 25 second run. Wouldn't do it until I shut the key off and let it sit for a bit. Not sure why but mine works fine overall. Never had issues starting it when it did that though.
#3
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I have noticed before if I bump the starter so that it runs for the 30 seconds or so if I try right after that the lift pump won't run since it is already primed. That might explain why the pump wasn't running. As far as why it wouldn't start....not sure on that one.
swordfish
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