The AntiRice

hello all, I am posting in reguards to a problem that I am having, and I am at the end of my rope.
My car is a 2000 Si with a jackson charger, Fuel pump,vafc, fpr,fmu.

The problem is, once my car has been driven around for a while, it has a terrible sputter at approx 4-5K rpms, and its random, and its violent. We have determined when it happens, the car looses fuel pressure completely, like the ignition is being switched off momentarily, however no other accesories lose power of any kind. First people told me and i tried to remove my VAFC, that didnt fix anything. Then we figured it must be the ECU, So we swapped ecu's with a known working one from my friends 2kSi and that didnt fix anything. Then we figured we try the FPR< changed the fpr to stock, still did it. Then we figured it MUST be the fuel pump, Changed that to stock, still does it. Then I changed the Fuel filter, still no help. we are in the process of changing the injectors right now, but i have a feeling that wont help either. The plugs have been changed, 2 times now just to be sure, and there is also a brand new cap and rotor. I also tried changeing the main EFI Relay, that didnt do jack. The car has just a tick over 28,000 miles.
If anybody has ANY IDEAS, I would really like to hear them, as I have checked and changed just about everything I can, and I am at my absolute end. Thanks

Brian


[Modified by The AntiRice, 11:54 PM 8/18/2002]

genop

are you running some sort of missing link or something like that so the ECU doesnt see boost?? Do you get a CEL??

00TurboEX

didnt see anything about the FMU, could it be sticking?? just a thought...

goodluck

david

The AntiRice

i am not running a missing link, the jrsc is after the map sensor.

I have not replaced the fmu yet, but the fmu only comes into play under boost to raise fuel pressure, this is occuring under light load no boost driving. right now i am running the stock fuel pump and have the fpr adjusted for stock pressures, not boosting at all.

Count Blah

Another thing that was not mentioned is that the stuttering and check engine light seems on come on at exactly 4.5k each time it happens (non-dependant on Throttle position, and with or without boost, it can be in vacuum and still do it, so its 99.9% not the JR FMU). Its almost like something electrical is triggering the fuel pump to stop pumping, as the fuel pressure gauge drops straight to 0, and then when the rpms are coming back down, the pressure jumps back up. The CEL also goes on for a second while the problem is occuring, and then goes off just as quickly as it comes on, so there is no code we can grab off the ecu, which is making this even more frustrating.

Anyone?!

-Todd


[Modified by Count Blah, 12:44 AM 8/19/2002]

redline

find a honda pgm tester and pull the code that way.

00TurboEX

sorry, in you original post, i didnt see the part that says it is not boost or vacuum dependent. by the way, i know what an FMU does but anyways, i hope you figure out your problem, so heres a bump for ya. good luck.

david

Kamin

is the fmu hooked up correctly?
i think you may need to check your fuel pump if all the fuel stuff checks out
check the ENTIRE fuel line
pump, fmu, rail, FPR, injectors etc.

first you need to pull that code tho.
you dont need a honda tool all you need is a paperclip.

brian b

remove your vafc and try it

Kamin

oh **** i never even saw that in his post.

The AntiRice

in my original post i said the vafc is out, and we also swapped ecu's to make sure it wasnt a bad ecu, so thats that one. The CEL only blinks on for a second when it bucks, and then goes out, it does not stay on solid. I know how to pull a code with a paperclip, ive done that a thosuand times on this car and other friends cars, but if it does not store the error in the ecu i cannot pull it.

The fmu is hooked up correctly, it has been installed and functioning for almost a year now, the car was dynoed and tuned 3 days after it was all installed and has ran flawlessly from then untill now. We checked teh ENTIRE fuel system, changed the fuel pump, changed the filter, changed the injectors, checked all the fitings and lines and whatnot, thats not it. I jsut pulled the plugs again (for the 2nd time in 2 weeks) and they are all jacked, (assumably because every time it loses fuel pressure it detonates a little)so i put in 4 new plugs,(again) but before hand we did a compression test jsut to make sure and it was 190 across all four. I just borrowed another map sensor from another 2ksi that we know works, and im gonna try changing the plugs and the map sensor and see if that helps, but it is a freak *** problem, and its been getting worse.
so i guess, TTT.

Brian


[Modified by The AntiRice, 2:40 AM 8/19/2002]


[Modified by The AntiRice, 2:41 AM 8/19/2002]

The AntiRice

No codes are stored, we tried to check them anyway. Changed MAP sensor, still is not resolved.


Fuel pressure is still being lost as soon as the CEL flashes, and we went through the entire fuel system and replaced with known working pieces, including the mail relay.

The AntiRice

latest update: Fuel pump loses power momentarily when the CEL comes on (which corresponds with the stuttering) Fuel pump relay has been replaced and is still in the car.

The AntiRice

TTT- can anyone trace where the yellow/green stripe comes into the FI relay from? I dont have a helms...

TIA

HybridKOOP

Going through the same thing with a DRAG 3 GS-R powered del Sol. Except in my case, no CEL... just a nasty sputter/popping and power LOSS when VTEC "kicks" in. The car runs 100x better with VTEC disconnected... very sad... and an ongoing problem for 2 weeks now. I'm baffled. Changed plugs, distributor, wires, checked fuel pumps, FMU, timing, fuel pressure... nothing.

I feel your pain, man.

- Louis

The AntiRice

well, we've narrowed it down to not being any of the stuff that we have checked/changed over the past 3 days. Basically, there is a freakoid short somewhere, or soemthing i dont know about that changes when the car warms up, because if the car hasnt been run for a few minutes or half hour, it wont do it untill about 5 or 6 minutes of running/driving. the car will reach 4-5K and the fuel pump will lose voltage but will regain voltage momentarily after. Using a probe and checking the wires on the fuel pump, its going completely dead for a half second, same thing upon checking the fuel pump wire on themain FI relay, but when i probe the fuse on the fuse box that is for this circuit, it does not lose power completely, only a little bit of voltage. I literally have no idea where to go from here, or what is even causing this. It makes no sense to me because it seems to be dependant on the car warming up. We thought it might be an o2 sensor, but i changed that too and didnt help at all. I cannot take it in to honda, they will basically blame it on one thing or another and give me my keys back with a bill for one hour.
Any ideas now?

turbogsr

You said you put a new cap and rotor. I don't know if that is including your ignitor. If you are still using the same ignitor, you might try switching that out for a new one.

The AntiRice

i havent changed the ignitor, i could do that but so far everything i have read on the internet about a bad ignitor points to the car not starting at all, my car starts fine, drives fine if i keep it under 4k, but after that, well, you've probably read it if you are reading this...
Am I wrong in that the ignitor will mostly affect the car not starting?

HidPerf

when you ahd the cap off, was there a bunch of red dust over everything? Honda's are notorious for bad distributor bearings. Cold engine, bearing moves free, engine warms up and clearances change, bearing locks momentarily causing crank angle sensor fluctuation. I believe the ignitor sends the signal for the fuel pump also.

The AntiRice

when i had the cap off, there was not red dust everywhere, but there were little speckles on a few of the contacts on the cap, and my car has *almost* 30K miles so i figured it couldnt hurt to replace the cap and rotor a little early.

What you said actually does help, do you think I shuold replace my distributor? If there was something locking momentarily and throwing off the crank angle sensor, isnt there a CEL for that? I dont have a problem with replacing parts, Its just i have already replaced so much and each time were were *sure* that had to be the problem...The first time this all happened was on the hottest day of the year (110 here) and its intermitent. The only thing Im trying not to do is replace stuff unnececarily as I have done thusfar, but I know if i take it to honda they will dick me for sure. I really apreciate everyones help, like I said I never would expect something like this to happen to a car that only has 28K, and the worst part is basically nobody has had the first clue on how to help me, but this might be promising info. Any other info is still apreciated...


brian

Spankee2K

could be a bad ignition switch...the electrical portion, or the fuse box itself.


[Modified by PressurizedB18C5, 11:43 AM 8/19/2002]

JRSCCivic98

You're not loosing power to the pump... you're loosing power to the ECU. On any OBD ecus if the check engine lights on at all (either then the obvious... I just stalled out thing) the code is stored in it and the light will stay on. No matter what. If you're loosing power to the ecu, then your pump will loose power since it is controlled by it and the ecu will clear the code once this voltage is removed from it... even for 1 or 2 secs... It doesn't take 15 secs to clear the ecu. Put the probe on the power going to ecu and see if that drops when this happens.

Also, check all of your ground wires... The ones going from engine to frame and whatnot. Sometimes a missing or disconnected wire will cause your engine to run like chit. Oh, and what do you mean by botched plugs when you pull them? If you're not under boost or you loose fuel completely you will not detonate an engine... that's how fuel cut works. You only get detonation when you have enough fuel going to engine to mix with air and give a 14 or richer reading. If you generally drop below that to 15.5 or higher, you will just loose power but your engine will not detonate. There's a limit on leaness that will cause detonation. Sparking pure air alone will not ignite... that's why it bucks.

Another thing to look at is if you have an external coil... that's probably gone bad or if you have an MSD ignition on it... mostly the BTM units... then that's gone bad. Had both happen to me with similar results.

Hope this helps...

Spankee2K

oh also check the ground wire on the T-stat housing in the engine bay.....that one will cause all your problems also!

Count Blah

Up

Evil EG

My car is having some of these same problems, it likes to sputter then throws a code. So heres a bump.