e30 318is fuel pump + obd1 s52?

[loonibab325i]

So i have a obd1 s52 e30 with 24# injectors using a stock m42 fuel pump from 318is.. my question is if i were in need to replace the fuel pump would another m42 pump be ok? or should I be looking into upgrading?

Here is my problem:

I drive the car, it drives great but after driving it for a while the car will just lean out and go on and off (the car stops getting fuel), then it gets fuel, then again no fuel in the matter of seconds, then dies.. The car cranks fine after it dies but it isn't getting any fuel, if i wait 30 minutes or so the car starts up just fine, acts a lil shady but starts up.. Also, while the car doesn't want to start the freaking fuel pump relay makes a crazy buzzing noise.. now I know you are going to tell me to check the relays and fuses but trust me, i've switched out this fuel pump relay many times, it's not the relay, nor is it the fuel pump fuse.. so i duno if i am getting a short in the wiring and getting something to damage the relay or what.. I have a huge feeling that this is just a fuel pump issue, maybe overheating and then dieing out? and then when it cools off it starts to work? but i don't understand why that gets the relay acting all crazy.. any advice would help.. I Think i'm going to start off by replacing the fuel filter (have no idea when that was changed last, the car is pretty new to me) and the fuel pump.

Thanks for the help in advanced, cheers.

-Abe.

[318isbmw]

Should be fine w/ m42 fuel pump. I'm runnin mine, although it needs replacing soon, but it works good, and I haven't heard others having issues with the fuel pump from the m42 cars.

[loonibab325i]

yeah, that's what I thought. Could it be that mine is just failing out on me?

[318isbmw]

yeah, that's what I thought. Could it be that mine is just failing out on me?

Yeah, it very could be. I would change filter, because I had some of those issues w/ my filter going bad, but also I'm still having issues w/ my pump, but I definitely agree that its in the fuel that your issue is. One idea to figure out if its the pump would be to find when it won't start and open up the line at the filter and try and start. If the pumps on its gonna spray, but if its not it won't. Odviously don't try for long, but just a second should give you your results needed.

[AL GReeNeRy]

i have had similar problems with my m50 into 318is swap. i think the swap engines overheat the old fuel pumps after a while of driving. i figured a 17 year old fuel pump designed to run a car with less than 150rwhp wouldnt be sufficient enough for what these new motors require. when i get a chance im upgrading to a 255lph which will definitely be strong enough. the stock m42 pumps are definitely enough to drive the car, but obviously cannot handle any kind of spirited driving

[loonibab325i]

i have been running mad rich for a while, could that have anything to do with it? thanks for all the great responses.

-Abe.

[318isbmw]

i have been running mad rich for a while, could that have anything to do with it? thanks for all the great responses.

-Abe.

I don't think so... Does it have a tune on it and stuff. Or I'm thinking in the completely wrong direction of the fuel system and am missing something haha. Been known to let that happen.

[loonibab325i]

I don't think so... Does it have a tune on it and stuff. Or I'm thinking in the completely wrong direction of the fuel system and am missing something haha. Been known to let that happen.

it wasn't tuned for a while, now it's got 24 # injectors TMS 3.5" afm, shrick cams and the TMS chip for all of that setup.

anybody know where i can buy a walbro fuel pump?

-Abe

[jogfrogjog]

ebay

[318isbmw]

it wasn't tuned for a while, now it's got 24 # injectors TMS 3.5" afm, shrick cams and the TMS chip for all of that setup.

anybody know where i can buy a walbro fuel pump?

-Abe

I dunno, I just saw that summit doesn't have em, not sure where to look, but I'd check out bimmerforums FI section and I'm sure that someone will know on there.

[JiXer]

it wasn't tuned for a while, now it's got 24 # injectors TMS 3.5" afm, shrick cams and the TMS chip for all of that setup.

anybody know where i can buy a walbro fuel pump?

-Abe

Not sure if you got this sorted out yet, but you definitely need a higher flowing pump. The M42 pump is smaller than the M20 pump and there is less than 30HP difference between the 2 of them. If that was enough for BMW to make a change then jumping up to another 100HP over what that pump was intended to feed is definitely going to be a problem.

J.

[Link]

Bump, any one know a real answer to this yet?

[mtlbloodshot]

I'm running a stock fuel pump on a M52 and when I give a big load, in high RPM the power just cuts off. I've been told that a E30 M20 pump will do the job. But other than that, starting and cruising the pump does fine.

[MR E30 325is]

I personally ran the M42 fuel pump from my 318is while I had a supercharged S52 under the hood.

No fuel cut out, even at WOT. The car had 30lb injectors to boot.

It is definitely capable.

Car made well over 300 horsepower. I don't know how you guys are having issues, but I was problem free.

Pump even kept up when I set my personal land speed record. Car was sitting at 6800 rpms for about 30 seconds at 187 mph.