Well... my first blazer pump lasted 3000 km.....
at the track last weekend it just up and died on me on a run up the track... wouldn't make more than 20 psi of fuel pressure.
So on Friday we installed a brand new blazer pump... a/f's looked good an everything was golden... drove the piss out of the car all night... it was a thing of beauty.
Saturday morning the car is a bit hard to start... odd... drove it around, and noticed the Af's dropping off HEAVILY...
Got the car home and pinched the return line - 50 psi max at the pump. What the hell. At this point I had less than 200 km on the pump.
Drove the car on Saturday night, it started cutting out at 3000 rpm with almost a full tank of gas...
Got it home again, pinched the return line - 30 psi max pressure.
WHAT THE HELL???!?!?!?! Can ANYBODY shed some light as to how the hell I am killing a BRAND NEW high-flow fuel pump in less than 300 km!?!? (Less than 180 miles)
Granted I am running 11 lbs of boost... but that fuel pump should take it. My FMU is set about halfway, so about 6:1 or 7:1....
Base pressure was 30 psi... so that's about 107 psi... that isn't too ridiculous in my opinion to ask of a pump that FREE FLOWS at 100 psi.
If anybody can shed some light as to what the hell is going on, it would be greatly appreciated. I'm at wits end, my wallet is MORE than dry, and I can't keep affording to do this... it's coming down to get the car running or just sell it because it's simply destroying whatever personal life I have affordability wise.
Thanks.
-Chris-
-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
the fuel pump is a stock unit outta another GM vehicle. it wasnt made to handle high pressure.
try a walbro 255 that is meant to withstand the high PSI.
Free flowing pressure is a LOT less stressful on a pump than having it in a system. Understandable that you don't want to pay $220 for a pump up there in Canadia, but I wouldn't keep spending money on GM OEM pumps just to keep blowing them.
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This is fine... I understand that except WHY have other people run this pump at medium boost like that and had no problems?
I don't think I'm asking too much of the pump to be honest.... I know SDSGT has run ihs pump for 2 years at 10-12 psi and it is still fine.....
What other factors could be killing these things?
I mean - I ran the other pump at 10-14 psi for 3000 km and it was fine... this one lasted less than 300 km... something isn't adding up.
-Chris-
-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
cleanliness??? have you tried cleaning out the tank or seeing if there is anything in the tank, just an idea.
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there is the high-flowing 255 liter per hour fuel pump for $116 CDN
Supercharged 2.4L
^^ I thought that one on highrev and the blazer were the same thing??? Correct me if I'm wrong thanks......
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yes it is the blazer pump, thats were I got mine, I have it in my car right now but it has a hesitation at start anyone have this problem??
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Are you changing the pump separate from the sending unit? If so, make sure there are no leaks between the pump and the fuel line connection outside the tank. I've seen it before.
If you're pretty sure the pump is junk and you can't warranty it, take it apart. Start with a pair of wire cutters at the bottom of the pump and use them to roll the aluminum body up like a sardine can. When you've got it taken apart farr enough, the bottom pieces inside the pump will fall out. You'll get to see the bottom of the armature, the copper tabs where the brushes contact. If those copper tabs are worn through, that's what's causing the pressure problem. There's usually 3 reasons why those tabs get worn down.
1) high mileage. Not a case here.
2) fuel level allowed to get too low too often. The brushes and tabs are lubricated and cooled by fuel. If the fuel level gets low and sloshes away from the pump for even a quick second, it hurts the pump. Think of it like oil sloshing away from the pickup tube in the engine.
3) contamination in the fuel wearing the tabs away. The fuel must be clean for the pump to live.
Also check your electrical lines for problems. GM is using smaller diameter wire on their fuel pumps than they have in the past. These pumps draw a fair amount of current and when fuel pressure is increased they use more current. In stock applications I've found that a tiny amount of corrosion can cause electrical terminals to get hot enough to melt the pastic connector they are in, which causes things like low fuel pressure and no-starts. IMO, the factory wiring should be replaced by a larger gauge wire when a larger pump is installed, but I know that most people get away without doing that.
good luck.
-->Slow
Nice, I just have also changed my pump for the blazer one. I Found that the assembly is very different from what i have seen or read in this forums. My stock assembly does not have the footpad black instead is like a plastic can an everything get into the assembly by the top. Anyway the blazer pump fit exactly but directions to install were different..
I upgraded my fuel pump because 2 stock pump failed prematurely, one at 30000 miles and the other at 45,000. I think not sure after changing the pump that the assembly was the problem the gas come into the assembly by an oriffice controled with a small rubber tap controlled by the fuel pump. My stock pump has a line that pushes gas against this rubber tap and allows gas to enter into the assembly. So i removed this rubber thing because the blazer line does not have this line to open the rubber gate.
I thing this gate has corrosion and isn't opening correctly so the pump gets low in gas and is wearing the tabs. So 2 fuel pumps started to fail.
I have run 200 miles with the new fuel pump and no problems and the car feels much better and it's running at 52 psi all the time I have no FPR. and don't know what psi is getting at full throtle.
So I thing it's a bad design of the fuel assembly. Maybe you are having the same problem because the fuel pump doesn't have the line to open the rubber gate.
A question.>
The assembly has 3 lines external. 1 is the sending line Green. 2 is the return line. and 3 the middle one line goes to a black box beside the Gas tank..
What is this black box. What would happen if i disconnect this line.?
Tnks
I been driving without an EVAP canister for about 10k miles now...no problems yet
