Turn off key, fuel drops to ZERO psi instantly. HELP!

#61
I think some of you are brain washed with chips being bad. LOL I've had that same chip in the car since the day I bought it. I HAVE removed it, and the only difference was my rev limiter kicked in sooner. It had the surging idle just the same. I've also had the timing at 6 degrees for aprox. 4 years.

Okay, now for an update. I put everything back together last night (stock injectors and stock mass air). Still didn't hold fuel pressure, but the car started right up. It stumbled just a bit, but after a few minutes it started idling just fine. I drove it around. Not once did it act like it was going to die! It didn't seem to quite have the power it did before. But I wasn't sure what to set the fuel pressure at. It's been a while since I've had the 19lbers in. Fuel pressure was showing a steady 40psi with vaccum.

I took a trip through town. Went to Wally World. The car ran really good. Started up each time, idled everwhere I stopped.

I did my load test going down hill in 2nd gear coasting. At first it didn't surge at all.... but then it started to again. But it was different this time. It still surged, but had a hanging moment where it would build up 500 rpm and instead of bouncing back and worth, it would bounce and hang, bounce and hang. Weird, but still wasn't as bad as before.

On my test drive, I tried to get the car to die. Blurped the throttle while holding the brake and forcing it to idle back down. It did just fine. Popped the hood when I got home. My C&L pipe had popped the M/A to pipe coupler loose on the bottom. Amazingly the car ran fine. I fixed it for the drive in the morning. I went to bed last night very happy.

---------------------

Fast forward to today. I get up, in a great mood. Go out jump in the car. I did NOT prime the pump like I did in the past. It took a slightly longer cranking session than I feel is normal before it fired. But it did start in the first turn of the key (barely as I was just letting up). Backed the car out of the garage. Car idled just fine. I was still happy. Took the mile and half drive to work.... car actually felt a little better. Perhaps my SOTP meter was in a good mood too. :)

Going down the hill, I could barely get the car to do the loaded surging... but it was there. As long as it idles and races good, I could care less. Still in a good mood.

I pulled up to my one traffic light I had to stop at on the trip to work. Sitting at the redlight... it started to stumble. Surging just a bit, but gets stronger and stronger. Car dies. :bang:

Starts right back up, but I could feel it was going to die again. I drove on to work. I sat in the turn lane at work. The car stumbled and almost died, but I gave it some gas and the rpms came back up. Pulled into the parking lot. I sat there in gear and watched the car surge 1,000 - 600 rpms, over and over. Good mood gone. I put it in park. The car jumped up to 800 rpms and idled just fine.

I plan to pull the codes when I get home.
 
#62
i have a similar problem.

ever since i bought my car, i would have to prime the motor twice to get it started.

doesnt always happen. sometimes it happens when i dont drive it for a while. sometimes just an hour after i went for a ride.

i was thinking its my fuel pump. so i ordered a 255HP pump. i have a kirban yet to install. i put a gauge on the fuel rail in the past like you did. after an hour of running, fuel pressure dropped off to zero.

no idling problems. just an occasional starting problem. it gets annoying and sometimes embarrassing.

if you figure it out, let us know
 
#64
I have until Saturday to decide if I'm going to buy another set of 24lb injectors from a friend for $125. Since the car is running crappy again, I'm not sure it's the injectors anymore. I'm going to drop the fuel pressure down and see where that gets me. Kinda strange the Fuel pump relay isn't an error code anymore. :bang:
 
#66
Just some info that might help i had a bbk fpr and had the same problem with my fp when i went into there web site and went into there most asked questions i found out most fpr are not designed to hold pressure so i went to a FMS regulater and the fuel pressure been fine and when i had my idel problem it was caused by my C&L maf so i went to a pro-m and problem solved , you might want to install your stock maf to see if this could be the problem or you could send it to PMAS which is the same company as pro-m but owned by the employes to have it tested .
 
#67
must b a stang said:
Just some info that might help i had a bbk fpr and had the same problem with my fp when i went into there web site and went into there most asked questions i found out most fpr are not designed to hold pressure so i went to a FMS regulater and the fuel pressure been fine and when i had my idel problem it was caused by my C&L maf so i went to a pro-m and problem solved , you might want to install your stock maf to see if this could be the problem or you could send it to PMAS which is the same company as pro-m but owned by the employes to have it tested .
Click to expand...

Post #61 - I put my stock injectors and Mass/Air back on the car. :D

I couldn't find the BBK info. about the fuel reg. But I did find this:

"BBK recommends that when doing any performance parts install on late-model cars and trucks, you unplug both terminals from the battery, and let it sit for a minimum of 2 hours, overnight if possible. You may also want to turn the head lamps on while the battery is disconnected to help force the remaining voltage out of the system. This causes the computer to "forget" its memory, and puts it into a re-learn mode. While some books say that the computer will reset after as little as 2 minutes, we have seen cases where it took overnight for the computer to "forget," and we feel it is better to play it safe and be sure the computer has reset. Once you have reset the ECU, reconnect everything and start the vehicle. Let it idle for 30-40 minutes without any sort of throttle input or gear changes (for automatic equipped cars). This means you must not hit the gas pedal during startup or anytime during this warm up.

This should give your computer a chance to calibrate and compensate for the added equipment, so that you will get optimum air/fuel mixtures, and a nice, smooth idle. You should also drive the vehicle around for 50-150 miles, as this will allow the ECU to accurately tune the car for best performance while driving. This should also allow for better gains from your performance add-ons, ensuring you get the most you can out of your new BBK products."

30-40 minutes of idling... wow... that's a long arse time.
 
#72
chickendreamer said:
So do you have 6 degrees timming with or without the spout in? Also if you can put the stock fuel pressure regulator in. Also, have you modified your EGR valve at all? Lots of people remove it, did you remove yours?
Click to expand...

Trick question.... 6 degrees with it out, but I drive the car with it in. :rlaugh:

EGR failed on me 2 years ago, kept sticking. I could poke the plunger with a screwdriver and all was well again. So I deleted it as noted in my reasoning for the codes. My car did run and idle fine a year ago.

I'm hoping to swap the fuel regulator tonight... but we'll see.

Keep the ideas coming.... surely we'll figure it out sooner or later. :shrug:
 
#73
gcomfx.com said:
"BBK recommends that when doing any performance parts install on late-model cars and trucks, you unplug both terminals from the battery, and let it sit for a minimum of 2 hours, overnight if possible. You may also want to turn the head lamps on while the battery is disconnected to help force the remaining voltage out of the system. This causes the computer to "forget" its memory, and puts it into a re-learn mode. While some books say that the computer will reset after as little as 2 minutes, we have seen cases where it took overnight for the computer to "forget," and we feel it is better to play it safe and be sure the computer has reset. Once you have reset the ECU, reconnect everything and start the vehicle. Let it idle for 30-40 minutes without any sort of throttle input or gear changes (for automatic equipped cars). This means you must not hit the gas pedal during startup or anytime during this warm up.

This should give your computer a chance to calibrate and compensate for the added equipment, so that you will get optimum air/fuel mixtures, and a nice, smooth idle. You should also drive the vehicle around for 50-150 miles, as this will allow the ECU to accurately tune the car for best performance while driving. This should also allow for better gains from your performance add-ons, ensuring you get the most you can out of your new BBK products."

30-40 minutes of idling... wow... that's a long arse time.
Click to expand...

I can see how that will work :nice:

however

I have found I can get a good pcm reset with a neg batt cable disco and turn on head lights or step on the brakes or honk the horn for about 5 seconds and then reconnect the batt cable. This will drain the caps in the pcm.

I have also seen a good reset with as little as 20 min of batt disco time.

What you are trying to obtain here is to clear the pcm's adaptive stored memory. I can see if it has been cleared with my Tweecer btw.

I have never done the 30 to 40 mins of idle thing myself.

After a pcm reset, you will need to idle at every condition possible before things stop changing. Things like, one accessory to all accessories on, turning the wheel, and the like. The pcm needs to obtain all the different reference points to be able to do its thing before you get a stable idle. This can take a while so you might wanna give it a day or two to settle down.

A whole lotta stuff is going on during this transition time :D

Grady
 
#75
gcomfx.com said:
My big thing is getting the car to idle in gear.... it does okay in Park or Neutral.

Maybe I should hold down the on brake and put it in gear when I first start it up after clearing the memory? :shrug:
Click to expand...

I can think of several things you could look at from the pcm's perspective which could make things better

BUT

You say things were OK before.

That just seems like something has broken down slowly over time and caused things to get worse and worse. :shrug: :shrug: :shrug:

btw ... after you idle in gear a few times the adaptive will first get its reference point and then start the change if it sees the need.

Grady
 
#76
Exactly, things were fine before. :shrug: My car used to be quite respectable and I ran the pi$$ out of it about every weekend. I moved away from the track and the "hub" of my car club where a lot of late night "fun" took place. Poor car didn't get it's bottle for quite a while. I think she's just being pi$$y with me. :bang:

Some good news... I'm going to have to take an extended lunch from work and drive a ways, BUT I'm getting my 24lb injectors flow tested for free. Hopefully they'll rebuild them too if need be.

:) Guess it's one perk of building this website: www.thepowerpalace.com - they are good friends with the auto tech teacher at a local high school.
 
#77
WTF - drove the car during lunch. Never died once. It stuttered a bit, but never actually died. LOL This is frustrating. :bang:

Plan is to drop fuel pressure a few psi more.... get my 24lbers tested and see how the car does over the w/e.
 
#78
I feel like a dog chasing it's tail. Okay, stock regulator is on. Fuel pressure still drops to zero. Before I call up the place I bought the new BBK fuel pump from... is there anything else it could be?

Second, I obviously had a good pump in the car, so I'm thinking the fuel pressure drop with the key off has little to nothing to do with the idling issues. It just makes it hard to start sometimes.

So I kept searching. I decided the car is showing lean plugs and I have pulled a code that the car couldn't adjust the fuel any more. Perhaps it's really the spark that is intermitten which is fooling the computer to lean out the car. :shrug: Also, I remember my problems back when I tried to put a used MSD 6AL box on the car. It was noisy and the car would cut out around 4 grand. So I unhooked it until I could get the car running tip top as I figured the cutting out was amplifiying another problem.

I had forgot to check the car at night in the garage with the lights out. So that was my next step last night. I discovered the replacement coil was sparking from the sides of the round cylinder to the black metal frame around it. It wasn't consistant, really quite random. It did it more when I revved the car up some.

So I pulled out my old stock coil. It wasn't quite as bad, but it did the same thing. :bang:

While under the hood playing with the coil. I thought my eyes were playing tricks on me. I could see an occassional spark in various places under the hood. Here's where it got tricky. I've heard the storys of the shock that a coil can give you, but damnit I want my car fixed! So I sat on the front cover and started wiggling the wires.

Not sure if this is normal, but I can touch the coil to dizzy wire in the middle and it will glow at my fingertips like one of those lightning sphere things IF I rest my other hand on the STB. :shock:

http://php.khk.tartu.ee/~drakan/Pildid/Niisama/Lightning_Ball.jpg

I put brand new red Taylor 8mm spiral core silicon wires on the car this last fall.

So what coil should I buy this time? Last one was the Jegs brand coil. Sales man told me it was the same as the MSD I was going to buy but cheaper, and didn't have their name on it. :(

Also are my plug wires just crap? If so what new kind do I get? I'm really getting tired of throwing money away on new parts that have issues.
 
#79
I threw this Performance Distributors ignition kit on mine....hot coil, beefier TFI, the wires speak for themselves....gap the plugs to 60....
I have never heard of any PD parts taking a dump...no issues with mine..

Sucks throwing parts at it....:bang:

30735.jpg
 
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