Killed another AEM fuel pump
Killed another AEM fuel pump Guys I've had this problem since I built the truck in 2017, and have thought I've fixed it several times. But every 3-6 months the same issue arises. They start to lose pressure under boost. I've had atleast 5 380/400 style pumps, first 1 was an aem 380, then I went through 2 China pumps, and the last 2 have been aem 400s. Running pump gas with a meth kit.
I have a 15 or 20 gallon eBay cell, foam is removed. 10an in the pump, it comes straight back and down into the pump. There's a 90 fitting but I believe the supply is fine. Then it's 8an out of the pump to a summit efi filter, then to the rails, out the other side rail to my automotive reg and 8an back to tank. Has a 10an vent. I'll note my pressure has never rose 1:1 with boost but it normally rises, when problem occurs it obviously drops. With this last new pump I have tried to keep the tank above 1/4 just in case it was a fuel heating problem.
Electrical- battery and fp relay are in back. It has 10 gauge coming off battery to the relay, the fuel pump is grounded to the battery. The fuel pump relay is controlled by the pcm via the factory Mazda wiring. Everything is 100% soldered, no butt connectors anywhere. Last time this issue was occurring I wired my volt meter to the pump and it wasn't losing power or ground.
I'm not gonna go through everything I've done, but at this point I can't see anything that would cause an issue. I'm beginning to think I'm just pushing them too hard? I nearly drive it everyday, and it's normally very hot in Alabama, it's been 6.35 at 115 in the 1/8 at 3580lbs. Maybe 700-750hp? Any ideas or theories?
I'm leaning towards a 4303 with the magnafuel filters, but I don't wanna kill a $480 pump either.
I have a 15 or 20 gallon eBay cell, foam is removed. 10an in the pump, it comes straight back and down into the pump. There's a 90 fitting but I believe the supply is fine. Then it's 8an out of the pump to a summit efi filter, then to the rails, out the other side rail to my automotive reg and 8an back to tank. Has a 10an vent. I'll note my pressure has never rose 1:1 with boost but it normally rises, when problem occurs it obviously drops. With this last new pump I have tried to keep the tank above 1/4 just in case it was a fuel heating problem.
Electrical- battery and fp relay are in back. It has 10 gauge coming off battery to the relay, the fuel pump is grounded to the battery. The fuel pump relay is controlled by the pcm via the factory Mazda wiring. Everything is 100% soldered, no butt connectors anywhere. Last time this issue was occurring I wired my volt meter to the pump and it wasn't losing power or ground.
I'm not gonna go through everything I've done, but at this point I can't see anything that would cause an issue. I'm beginning to think I'm just pushing them too hard? I nearly drive it everyday, and it's normally very hot in Alabama, it's been 6.35 at 115 in the 1/8 at 3580lbs. Maybe 700-750hp? Any ideas or theories?
I'm leaning towards a 4303 with the magnafuel filters, but I don't wanna kill a $480 pump either.
It very well could be. It seems to always start doing it intermittently on higher boost. Then it will start doing it at any boost level. This pump has only acted up 2 maybe 3 times so it may be ok if I add another 1, maybe?
Thanks for the reply Joe, but what would you do next? Add another aem or a 4303?
Thanks for the reply Joe, but what would you do next? Add another aem or a 4303?
Restricted User
Joined: Mar 2014
Posts: 7,192
Likes: 109
From: Ohio
I made 600 wheel on a single 380 with E85 without losing pressure. Haven't tried going above that on a single pump as I have 2 and the 2nd one kicks on around that boost level.
Your fuel system sounds like its up to the task. What are you using for a pre-pump filter?
What is your voltage doing in boost? Its a lot more common than most think to have an alternator shut off at high RPM, dropping your pump voltage to 12v or less.
Your fuel system sounds like its up to the task. What are you using for a pre-pump filter?
What is your voltage doing in boost? Its a lot more common than most think to have an alternator shut off at high RPM, dropping your pump voltage to 12v or less.
Damn, there's not a pre filter any more. With the first pump I thought it was restricting it so I deleted it to test it. I remember I had planned to get a bigger better 1 and just never did because it didn't make a difference.
Last time I checked the pump voltage stayed steady at 13.5 at wot. I was having issues with volts dropping above 6000rpm which was fixed with a bigger alt pulley.
You think something is getting past the little plastic filter in the pump and killing it? I have never found any debris on it or in my post filter. I wanna say I read it filters down to 150 micron, that could be my whole issue tho. Post filter I believe is 10 micron
Last time I checked the pump voltage stayed steady at 13.5 at wot. I was having issues with volts dropping above 6000rpm which was fixed with a bigger alt pulley.
You think something is getting past the little plastic filter in the pump and killing it? I have never found any debris on it or in my post filter. I wanna say I read it filters down to 150 micron, that could be my whole issue tho. Post filter I believe is 10 micron
Joe I think I've decided to add another 380 and hope the 1 on it now will live a while. I'm gonna add pre filters and a bigger post filter. My question for you, are you still running both your pumps at the same time? I have the aeromotive 13129 reg I believe with 8an return, just worried I won't be able to regulate it down with both pumps blazing.
Restricted User
Joined: Mar 2014
Posts: 7,192
Likes: 109
From: Ohio
I have a 13129 in my nova with a pair of Aeromotive 340 pumps running full time and it does a fine job of regulating pressure down.
The AEM 380s are staged in my corvette, since I'm still running the stock truck regulator.
The AEM 380s are staged in my corvette, since I'm still running the stock truck regulator.
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Verdad Gallardo It could be, I replaced the element not very long ago. The element according to the summit rep is supposed to flow 150gph. And atm it is a very intermittent issue so it won't be an easy check. I have a 40 Mic filter I could throw on for a few days