new to me, 98 M3
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ok I'll try that today. Only 1 line coming out of my fuel pump. The return lines are in a separate spot on my car (rear driver side of the tank)
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yep, i for sure had the pump, i pulled it to inspect it as well to make sure the filter wasnt dirty.
I just pulled the vacuum line on the FPR and it was dry. Is there any way to check for leaking injectors? I think I'm down to that as being the only thing I haven't checked. Other thing I could think of would be my CCV but that seems OK. when I googled symptoms of that being bad they said open the oil fill on the valve cover and your car would start sounding like Chewbacca. Mine checked out fine for that.
ugh...refuse to take it to a shop
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My only experience with leaking injectors is when the car has a hard-start condition after sitting overnight. The problem injectors revealed themselves by pulling the plugs and watching one or two jets of fuel spray out of one or more cylinders while cranking (the fuel that pooled up being pushed out)
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hmm, yeah i don't have that symptom.
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At idle with my foot off the gas my '99 M3 sits at 17%/18% throttle. Not sure on the rest of the numbers though. When I get back from my trip I can see what my car reads for the rest of the parameters you posted to compare
Company that made the Eurosport SC isn't around anymore. TRM tuning in GA installed it, not sure if they do actual programming to customize the tune or if Eurosport gave them the tune.
I'd think it's still something with the car as it was fine for a little while. Plus it's only showing the out of wack short term fuel trim number on bank 1. I think I'll swap 1-3 injectors next to see if fuel trims move to bank 2. At least that's free to try. If that doesn't show anything I'm stuck. I suppose professional smoke test next just to be sure, but I'm almost positive I don't have any leaks.
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At idle with my foot off the gas my '99 M3 sits at 17%/18% throttle. Not sure on the rest of the numbers though. When I get back from my trip I can see what my car reads for the rest of the parameters you posted to compare
small update. Took car into Crestwood Auto clinic in Madison for diagnostics. They hooked it up to their machine. Codes ran a little deeper than I could get with my scanner.
227, 228 Mixture Deviation Cylinders, 1-3,3-6
202 O2 Bank 1 control limit
242, 243 Misfire Cylinder 5,6
They said car is actually running fine under OEM bmw specs and wouldn't trip the CEL if it weren't for the SC, injectors, etc. I kind of suspected that. They said the tune likely needs to be redone. I perhaps lost it unplugging the battery? I've reached out to three tuners around here to see what they think and pricing for a new tune. Accumoto in Waunakee, Capitol Tuning, Performence Engine in Middleton if anyone has experience with any of them.
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I would be surprised if any of them can do it.
here is a helpful link if you want to tune it yourself or have the programs so they can tune it.
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Does anyone know if you can make live adjustments on OBD2 Motronic? I know for OBD1 and previous versions of Motronic it requires removing the EPROM, plugging it into a chip reader/writer and not being able to do it live.
I'd definitely have a shop do a dyno tune if possible, would be well worth the money.
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Does anyone know if you can make live adjustments on OBD2 Motronic? I know for OBD1 and previous versions of Motronic it requires removing the EPROM, plugging it into a chip reader/writer and not being able to do it live.
I'd definitely have a shop do a dyno tune if possible, would be well worth the money.
Ms41 can be rewritten in the car but not while running, you have to jump some wires on the 20 pin connector to power the ecu.
however testo datalogger is extremely good and free (donations excepted)
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yeah, all that coding stuff is completely foreign to me.
One companies response was " There are two steps to this, well three possibly. First I would like to take a look at the car (@1 hour) then if all checks out I would put it on the dyno and see how the tune is. At that point we make decisions and if you have or can get the software I can tune it if needed. "
I don't know what software he's talking about. I thought they did that and that was the whole point of the tune? Still waiting on the other two companies to respond.
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Thanks Snap for that offer, hopefully don't need to take you up on that, but maybe. Here's an update.
Picked up a fuel pressure guage, if you remember I couldn't get the one from Orileys to work. Grabbed one at Harbor Freight, hooked it up to the schrader valve at the fuel rail. Here's my results, im not 100% sure I did this properly.
First, i put ignition on but didn't start the car. Pressure went up to 42ish psi, and started dropping reasoably quick, down to about 30 psi after 2 or 3 mins with ignition still on. This is probably a clue for something. Did this each time with the vacuum line going into the fuel pressure regulator on or off.
Another test, started car this time. Pressure with vacuum line attached at FPR 41/42 ish. Took vacuum line off it jumps to 51/52 psi. I believe that is spec for the S52 engine. I also gave it solid rpm of 2500 and held steady at 41/42 with FPR attached. When giving quick bursts of gas it did just a quick spike.
I also noticed while FPR was plugged and unplugged with car running it would bog down a bit, so I believe that is working properly.
What has me concerned is i read I should be holding steady pressure with just the ignition on, correct? It's definitely dropping. Injectors or something with fuel pump? Again I'm running a bit rich it appears from my fuel trim numbers.
Thanks again experts!
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51 psi is 3.5 BAR which is correct.
The pressure bleeding off with the engine off means either your top injector o-ring leaks, or the injectors themselves leak.
It would be in your best interests to pull the rail and injectors and see which ones are leaking since an injector that bleeds fuel into a cylinder during a high rpm shift or at the rev limiter can cause detonation
Your injectors are firing against 14.7psi of ambient air pressure,
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probably a stupid question. Can I pull the rail with injectors attached and pressurize the system (not start car) to see if any leak? Not sure if there's a side effect that could harm anything I'm not thinking of.
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Yep, that would be the way to go.
You dont need the electrical connectors attached so that gives you a little more flexibility to work with. Put something down to catch any fuel that may leak then just prime the fuel pump by turning the key to "On" You can also jumper the fuel pump relay to let it run continuously. This doesnt hurt anything.
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Hey again. Sorry to keep pestering, really wish i didnt have to. You all just respond so quick
Update: Unplugged injectors, turned on fuel pump watched injectors, no leaking.....but pressure still drops. So, car runs steady at 51 psi with FRP unplugged, 41 psi with it plugged in. When I start the pump FPR plugged in (not starting the car) the gauge instantly goes to 51 but immediately drops to 41 psi then pressure bleeds off somewhat quickly.
I started the car and turned it all the way off and pressure holds, doesn't drop off. Tells me it doesn't appear to be siphoning back when car is off, I've never had a hard start problem so it's not a check valve. When I pinched the fuel lines at the back of the rail the pressure on the gauge would go up and down, doubt that means anything.
So, still maybe a partially functioning FPR if there's such a thing? Hate to throw $90 at one not truly knowing. Or maybe it really is tune related. Out of ideas.
I promise to get some nice pictures up to have something fun to talk about. New rims are on, look great!
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