When i did the turbo build on my car, a buddy of mine mounted the FMU on the firewall (which i found out is a no-no) directly behind the FPR.

I thought i was having fuel pump problems with my blazer swap, but after correcting the problems with that AND replacing the pump, I still having a bit of cutting out.

I was searching a few dyas ago and came across a post where someone mentioned that "it sounds like your FMU is getting to hot. Move it.". When i first finished the pump today. The car hadnt been started at all and was dead cold. When i first fired it up, and ran great, up until it reached temp, about 195 give or take a few degrees. So i popped my hood and started looking around and felt the FMU and it was REALLY hot, alot hotter than I expected. I plan to move it over to the strut tower. Do you guys think this will correct my problems of what feels like pressure cutting in an out.?

i dont have an FMU but I hvae an afpr mounted on the firewall. mine is mounted close to the strut tower though and not above the exhaust (which is probably why its a no-no). is it above the exhaust??

I don't think you're supposed ot have any fuel component mounted anywhere on the fire wall.

Anyway I am almost 100% convinced this is my issue, beucas eif my car is cold and I start and then drive around all is well, once at temp, if i shut it off and let it sit, and the heat from the turbo/engine soaks into the fmu and from there I start having problems. Once I have time, I will move it and see if it corrects the problem.

So just a heads up, if you have an FMU, mount it where it will stay cool.

this is the same exact problem im having im going to move mine next to my battery so the cold air blows on it would that be 2 far ??

My FMU is mounted right above my turbo on my firewall and I have had no problems .....

Deekster Jones wrote:My FMU is mounted right above my turbo on my firewall and I have had no problems .....

What fmu do you have?

I have an OBX 8:1, and believe its made out of 100% aluminum, so it seems reasonable to assume it could be expanding and messing things up. I guess we'll find out ehh?

mine is the Cartech (begi) 2025.

Yeah, you have a good FMU haha.

I will be purchasing one of those soon as fund are kinda tight. This is what I get for going with cheaper stuff.

i have the obx 8:1 also maybe thats the problem

I had an inline fuel pump mounted on the fender in my first setup and after long periods of time the car would sputter and lose power and eventually die. After hours of pondering we came up with the conclusion that the fuel pump absorbed enough heat to turn the fuel in the lines to vapor this entailed vapor lock well thats what my boss said and hes been working on cars for a while. You may have good luck moving it. Try mounting it to one of the bolts that come off the power steering pump thats where my fmu is mounted and no problems.


*2012 mazdaspeed3*