Fuel Pump or Vapor Lock
09-15-2010, 03:44 PM
#1
On The Tree
Thread Starter
iTrader: (1)
Join Date: Apr 2009
Location: Greenville South Carolina
Posts: 117
Likes: 0
Received 0 Likes
on
0 Posts
Fuel Pump or Vapor Lock Hey everyone trying to figure out if I need to replace my fuel pump or if it is vapor lock.
What is happening is about 3 months ago I was at the store. I was only in the store for about 5 min, came back out car primed and start fine, I got about 2 blocks away and the car shuddered and died as soon as I put in the clutch, but restarted without a problem and didn't give me any more problems till I went to a track day event. I had over half a tank of gas.
At the track I ran 4 20 minute sessions, on the last session I came in the fuel pump was making a loud whine (about 3 times louder than the priming sequence), stalled out. This time I cut the car off and tried to reprime, where it didn't make a noise for about a second then it make a loud noise that sounded like a dying cow. Basically it sounded like it either had no fuel or something was clogging it. I let the car sit for about 30 min and it primed and drove 3 hours home without a problem. I had around 5 gallons left in the tank by the end of the 4th session.
Last week I was driving around town for about 30 min and it starts making the loud whine again, but did not try to stall at all. I got to the store and sat around for a while, it was making the bad priming noises, after a while it stopped doing that. Cranked it up was quiet for about 5 minutes but went did not give me any problems on the 15 minute drive home. Again half tank of gas.
What gets me is the pump was replaced around 2 years ago and only has around 15-20k on it, I was told by the previous owner it was an ac delco unit.
mods are in sig.
What is happening is about 3 months ago I was at the store. I was only in the store for about 5 min, came back out car primed and start fine, I got about 2 blocks away and the car shuddered and died as soon as I put in the clutch, but restarted without a problem and didn't give me any more problems till I went to a track day event. I had over half a tank of gas.
At the track I ran 4 20 minute sessions, on the last session I came in the fuel pump was making a loud whine (about 3 times louder than the priming sequence), stalled out. This time I cut the car off and tried to reprime, where it didn't make a noise for about a second then it make a loud noise that sounded like a dying cow. Basically it sounded like it either had no fuel or something was clogging it. I let the car sit for about 30 min and it primed and drove 3 hours home without a problem. I had around 5 gallons left in the tank by the end of the 4th session.
Last week I was driving around town for about 30 min and it starts making the loud whine again, but did not try to stall at all. I got to the store and sat around for a while, it was making the bad priming noises, after a while it stopped doing that. Cranked it up was quiet for about 5 minutes but went did not give me any problems on the 15 minute drive home. Again half tank of gas.
What gets me is the pump was replaced around 2 years ago and only has around 15-20k on it, I was told by the previous owner it was an ac delco unit.
mods are in sig.
09-15-2010, 06:48 PM
#5
TECH Regular
Join Date: May 2010
Posts: 481
Likes: 0
Received 0 Likes
on
0 Posts
Yeah its your fuel pump, vapor locks don't happen on injected motors for a reason. The higher the fuel pressure, the more it takes for the gas to boil in the line, therefore they can withstand more heat that the same gas line at 5psi.
The trap door is easy to do and takes about an hour and a half if you take your time. Personally id make it L shaped so you can unsnap the lines easier. Do a search, there are a coupple of posts on this subject.
The trap door is easy to do and takes about an hour and a half if you take your time. Personally id make it L shaped so you can unsnap the lines easier. Do a search, there are a coupple of posts on this subject.
