Fuel injector replacement, needed at what mileage?

TriX5 · #1 12-17-2024, 04:43 PM

At present the fuel rail is off the M62. I recently replaced all eight coils as performance quickly degraded and misfires started to be a problem. Now just under 170k miles and I have been wondering how long the injectors will survive. Mine are probably the originals as I owned it since 40K miles.

Anyone have any specific thoughts on when to replace them? Or wait for one to fail and then pop a set of 8 in? FCP has Bosch injectors in stock and now seems a handy moment to put them in....

X5chemist · #2 12-17-2024, 05:35 PM

Ohm them out. How close are readings? I would base my decision on readings. Carb cleaner would be good to clean them. No way to fire them though. Mine have 167k miles and still run great.

At minimum, replace the o ring seals.

Henn28 · #3 12-17-2024, 06:31 PM

As an alternative, you can have them cleaned and flow tested. I bought a 540i rail and 8 injectors off of eBay and had them shipped to a business in Houston (Injector RX, I think). He cleaned the whole mess, flow tested them and sent them back to me with a little report card on each one showing they were within OE spec.

My google skilz show two places in MD. One is in Severna Park and the other is in Darlington.

All that said, I will likely replace all 8 the next time I have the intake off. At 23 years old I figure do it when the intake is off, or be forced to take the intake off when it is less convenient. I’m going to swap the M60 intake on my 4.6 for an OE 4.6 version at some point this year and will do it then.

TriX5 · #4 12-18-2024, 10:06 AM

Thanks guys, great info, perhaps best to have the current items checked first and then decide to keep or replace. I had replaced the seals on the injectors a year or two ago, they seem quite durable.

This morning I sent JCL Injectors in Darlington an email requesting a price for a cleaning and testing as they do not have anything on their website. Darlington and Severna Park are both less than an hour away from me so that works.

Henn28 · #5 12-18-2024, 12:21 PM

Quote:

Originally Posted by TriX5

Thanks guys, great info, perhaps best to have the current items checked first and then decide to keep or replace. I had replaced the seals on the injectors a year or two ago, they seem quite durable.

This morning I sent JCL Injectors in Darlington an email requesting a price for a cleaning and testing as they do not have anything on their website. Darlington and Severna Park are both less than an hour away from me so that works.

I can’t recall what it cost me when I had the injectors cleaned and tested. I needed a rail and the injectors cam with, so I figured it was worth doing for my motor swap project. Let us know how it works out.

srmmmm · #6 12-18-2024, 12:28 PM

My '02 had 389,000 miles on the original injectors when I sold it. I only ran Shell gasoline and never used any fuel system cleaners.

Currently have 130,000 miles on my '16 F15 and 105,000 miles on the CEO's '14 F32 with no fuel system issues, again though, only running Shell gasoline.

TriX5 · #7 12-19-2024, 03:30 PM

The Darlington outfit never responded to my EM. (Not surprising around here). Severna Park quotes $120 on their website. I am running out of time to mess with that and given the feedback on this board I guess another 100k on the original set should not be an issue.

Last night I put the lower oil pan on and the passenger side drive axle support. This morning I picked up the O-rings for the oil filter flange. That will be the last bit of maintenance before putting the front diff on the upper oil pan and setting the engine back on the sub-frame. Tomorrow I am expecting the GAS timing tools for the cam reluctor rings. Let's see how far I can get in the next 48 hours.

EDIT: Not too bad for an afternnon's work. The engine is back on the sub-frame and the transmission is mated with the engine once more. Always so much fun to put the bolts in the flex plate..... The GAS jigs for the reluctor plates came in the mail at 6pm so that literally took me 3 minutes to set up.

Tomorrow I will put the transfer case and the cross brace back on. Then the upper timing covers and valve covers will find their way back on the engine. Finally, the power steering pump and the belt tensioners will go back on. Getting the engine lined up under the car will probably not happen until Saturday which is my last day wrenching until after a holiday trip with the wife and kids.

BimmerBreaker · #8 12-17-2024, 09:49 PM

I have engines with 200,000+ miles on original injectors, I don't necessarily consider them to wear out at a given mileage. As long as the fuel filter does it's job to keep clean fuel flowing to them there really isn't much in them to wear out - newer, direct injection injectors are a different story. If I had a car sitting for awhile - I'd be more inclined to replace, as various environmental contaminants can clog them when sitting.

With that being said, I replaced them on a recent engine rebuild I did because they only cost a few hundred bucks and I was already in the engine rebuild for $2k+ at that point and didn't want to leave anything out.

FCP has M62 injectors for $264 for a full set. Send them straight to someone to flow test if you want, I probably wouldn't bother on new or rebuilt injectors though - the rebuilt ones (by GB anyways) are flow tested after being rebuilt and I assume the new ones are too. It's a little cheaper to get your current ones flow tested - but after flow testing, shipping (if required) and new o-rings I wonder how much you'd really save.

Not sure what ohming them out is going to tell you... the more common failure is insufficient flow or uneven flow between injectors.

Factory6speed · #9 12-20-2024, 09:57 AM

I just did new Bosch ones on my E36 m52, not cheap.. Once in a while it would have a little hiccup at highway speed, like an injector wasn't firing. The number 4 one was pretty carboned up and clogged, actually all 6 were a mess but #4 especially was different. I removed the original 1996 fuel filter back last March, I'm sure that had a lot to do with it. 156K miles.

I think they are still good, and they don't make these kind anymore, the large pink ones. I will be sending them out for the rebuild service. Race German offers that I'm going to try them. The car is running amazing, but I did about 75 other things at the same time so I can't say how much of it is due to the injectors, I'm sure it's part of it. Expensive but nice to get out of the way.

Henn28 · #10 12-20-2024, 11:33 AM

Quote:

Originally Posted by Factory6speed

I just did new Bosch ones on my E36 m52, not cheap.. Once in a while it would have a little hiccup at highway speed, like an injector wasn't firing. The number 4 one was pretty carboned up and clogged, actually all 6 were a mess but #4 especially was different. I removed the original 1996 fuel filter back last March, I'm sure that had a lot to do with it. 156K miles.

I think they are still good, and they don't make these kind anymore, the large pink ones. I will be sending them out for the rebuild service. Race German offers that I'm going to try them. The car is running amazing, but I did about 75 other things at the same time so I can't say how much of it is due to the injectors, I'm sure it's part of it. Expensive but nice to get out of the way.

As long as we are talking injectors, I’m wondering if anyone is familiar with Bosch EV14L type injectors? I’m looking at a different fuel rail for my motor project and it is only compatible with this type injector. I’m not even sure what “type” injector our OE Bosch ones are.

I’m considering how to clean up under the hood of the car I swap the m62 into and a large part of that is reworking the engine harness, but the rail isn’t very clean looking either.

Forgive the thread drift!