silence

had a problem with the return hose to the fuel filter- came off while driving (downstream of my rising rate fuel pressure regulator "fmu")

wasn't sure what happened, but gauges all looked fine (fuel pressure was steady at 51-55 or so as it should be out of boost, so i thought things were safe) and car ran fine (just no rising fuel pressure under boost- which i quickly realized and kept it out of boost completely etc.. there was no check engine light.

put things back together and pressurized fuel system etc. and things seemed good- started it up to a check engine light and lumpy bad idle (almost like i had a vacuum leak- which i tested/checked for).

any ideas?

i'm resetting the computer now by disconnecting battery. am i safe to start the car back up?

any recommendations for a code reader that will work on my car? I'd like to get one anyways and it would probably have been awesome to have to diagnose this problem.

thanks

-drew

ohlord

at
http://www.harborfreight.com/cpi/cta..._stores.taf#MN
for the 94169 obd2 scanner if store near you take the printed ad from the web site and they will price match the internet price.Nice unit,reads,clears,reads I/M readiness codes.
Check all lines,run it and read the codes.The 202's can set some odd codes for systems not included on that model.So read,write down and post all codes pending and active so peeps can take a look and give you some direction if you need itSeems like you know her pretty well though
ohlord
if you really want to get involved with her more get the
www.autotap.com
unit for about $199 laptop pc based real time scanner,reads values,temps,voltages,resistance,o2 values,IAT,sensor values and more.
It is not an SDS but a pretty good tool for the money if you are an above average Diy'r.

silence

i think i will order up the autotap unit actually

think i could be running on 7 cylinders? why/what's best way to check? like i said fuel pressure is steady and that seems to have been the only system affected. It's odd that it ran fine up to when parked- despite the apparent issue and now isn't running well after the problem was apparently fixed.

or i could just wait until i get more info from codes (i will not be towing it to a dealer though despite the fact that i now have a car hauler- so codes won't be until a scan tool gets here)

what you think?

-drew

ohlord

have an autozone store near by you can borrow a scanner and get the codes for free while you wait for the autotap unit.Post the code probably something simple.Don't start throwing parts at it ,that is my advice.Get the codes and let's take it from there.
ohlord

silence

yeah, i got all the time in the world basically!

will autozone let me borrow it?

ohlord

You give most of them a refundable deposit and the unit is free when you return it.plug it in under the dash,read the codes,post them for all to see and return unit.
ohlord

silence

will do-

probably be a couple days before i get around to it.

-drew

ohlord

the hegebegees if I don't drive a Benz or MG's for a day,how you can go for a few days is beyond comprehension
ohlord

silence

i'll be riding my Specialized S-works and driving the Tahoe and G35x. The Tahoe is really my daily driver around town- quite exciting eh?

to be honest i've only driven the C43 twice in the last 3 weeks sincei moved (and for a total of maybe 40 miles).

I will drive it a bit more often once i get everything moved in and sorted etc. assuming I/we can fix whatever is wrong with it without having to save up funding.

-drew

silence

ented scan tool from autozone

no codes found

started car in attempt to get it to throw code- started fine then slowly idled down to not running and actually shut off (over 30 second period). Had symptom which i could attribute to running out of gas... possibly (the way it idled down and shut off). did try restarting and it ran for about 10 seconds before doing the same.

remembering now that when i started it yesterday initially after putting things back together it started/idled normally for at least a minute or two before the choppy idle started.

no further time to test today- think i got something in my fuel filter? or something along those lines?

thanks for any help

-drew



btw- DID get my Explorer started and running for the first time this year this morning! looks like she will be making the trip to my new house this weekend.

silence

thought about it a bit while at work (work evenings) and just started to troubleshoot now quick for a second before bedtime.

still no codes. however, i have found that i have no fuel flow to the front of the car NOR do i have any noise from the vicinity of the fuel pump with the key in the "on" position.

I decided i didn't fully trust my fuel pressure gauge and started pinching hoses at various places- eventually found that it wasn't pressurized everwhere. guess i better rethink where my fuel pressure is taken from, eh?

i have a little project to finish up on the Tahoe in the morning (need to get it ready to bring my explorer here this weekend) and then hopefully i'll begin tackling this issue.

-drew

silence

fuel pump not running

no time to further troubleshoot under the car (or to lift the car actually)

will hook up power direct and possibly swap fuel pumps tomorrow

is there a fuse or relay for the fuel pump power? where is it? i checked the obvious locations.

MarcusF

The car starts and runs for a few minutes, and then dies. So the fuel pump must run initially, and then it quits.

This is just a guess, but on every Bosch ME system that I've worked on or read about, if the MAF doesn't report incoming air, the fuel pump is turned off. Is your MAF unplugged?

NitrogenBalance

If I remember, the fuel pump fuse is located in the rear next to the battery.

Didn't you just upgrade the F.pump? was it a new part or used?

Also, where are you picking up the reading for the F.pressure gauge? Mine uses an electric sender right before the fuel rail at the motor.

silence

i'm using that same location (the last bit of hose before it goes all metal in the fuel rails...)

I upgraded my fuel pump to a pump that randomly came used with my supercharger- i don't think it's the pump's fault either way. Whatever happened with my hoses down there probably had it quite overworked/possibly pumping air.

thanks for letting me know where that fuse is- any chance you can give me more detail/the number etc.. my stereo makes that fuse box a real pain to get to.

i still have stock pump i can switch back to to confirm that this is the issue.

I will go all the way up to the "044" bosch pump if the pump is messed up.

i will also swap to an adjustable fpr



after i get this sorted out (assuming there isn't something worse than i think going on) i'm also going to plan on swapping injectors when i put that new intake manifold on such that i can run lower fuel pressures and set myself up for some nitrous.

silence

ah- would be true BUT reread all of the above... first it was just idling poorly, then it did what you described (once), then it only ran for 10 seconds, then 3 and now it doesn't start at all... and there is 0 fuel pressure at this point.

my wild guess is that the pump was overworked trying to pump air or pump past a blockage (if so=not good news) and that now it has either burned out or blown it's fuse/relay. The bad idle was due to poor fuel flow/low pressure then before i figured out what was wrong the pump completely stopped (broke or blew relay) and now the car is getting no fuel.



edit- i realize the confusion probably came from my doing a bad job describing the symptoms

NitrogenBalance

The fuse box located in the rear has a card with it indicating what fuse is what.

I've got a vortech adjustable FMU dubed "super FMU" that my tech opened up and never put back together. The fixed rate FMU worked fine for us. I have no idea how to put it back together or where each part goes. It's all sitting in a box. Feel like messing with it? Otherwise the BEGI units are supposed to be great and priced well. The vortech unit is like $300 or so.

silence

yeah, i'd be up for trying to figure it out

i just really want to lower my fuel pressure in anticipation of nitrous and my future plans (thus larger injectors and less fuel pressure)

silence

found that i had blown fuel pump fuse- ran 12v directly to fuel pump

system pressurized but not fully (something around 15 psi throughout rather than the 50 it normally has)

didn't trust the reading from the gauge (since it WAS reading 50 when this problem started) turned key and car stumbled for about 5 seconds and shut off.

thought about things for a bit and decided to dig into the original problem a bit more (as it seems to be the most likely source of my problems to me)

took the same hose off that had come off before (the last leg of my fuel return line/the piece between my rear mounted fmu and the fuel filter)-- found it completely dry.

next removed the return line BEFORE the fmu and found that it was also dry

shouldn't those lines have some fuel in them? How do i purge them? what's going on...????

I simply don't know enough about these details of my fuel system to continue troubleshooting without a bit more direction, so i'm counting on you guys!

specifically- when should there be fuel in the return line? does my return line need to be purged in some way? why does the return line run back to my fuel filter (i'm assuming it just dumps back in there and recycles from that point, eh?)? have i missed something in my troubleshooting.

MarcusF

The theory behind a return line isn't complex.

The fuel pump sends fuel to the fuel rail. At the end of the rail is the fuel regulator. The regulator is designed to bleed off excess fuel pressure. It does this by diverting fuel down the return line. Ordinarily, there’s fuel in the return line any time the engine is running. I don't know the pressure setting of your OEM regulator, but I'd be surprised if it were less than 3 bar (43.5 PSI). If you're only seeing 15 PSI, that's why the return line is dry - there isn't enough pressure to trigger the regulator. Also, one bar probably gives the injectors a lousy spray pattern. That, and the engine may be running pretty lean.

SeeKlasse

do you ride an s-works roadie or the full suspension mtn? i ride trek carbon bikes, 5200 roadie and 9800 mtn. both very souped up, nice to see another biker in here

silence

s-works road bike

marin pine mountain for xc riding- would really like a newer better xc bike.

thanks for the fuel help- found same info elsewhere etc. (confirmed it) will be doing more troubleshooting soon

SeeKlasse

just pick up a nice frame off ebay and build it up. thats what i did, i got my 9800 carbon frame off ebay, came with crappy wheels but it was full xtr, paid 550. ive since laced up a set of chris king hubs to ceramic rim rear and disc front, put a manitou r-seven 100mm disc fork and god knows everything else has been upgraded. btw im rockin the thomson stem and seatpost, proudly manufactured here in Ga (macon). unless youre out in colorado or california i would def recommend a hard-tail

silence

probably not until next year, but hopefully as soon as possible

ohlord

fuel line routing.
ohlord
no codes even pending"