Three days ago I ran out of fuel. I put in a jerry can and the car fired right up and took me about 5 blocks before stalling at a stop light. It wouldn't start... I figured I had killed the fuel pump from running it dry, but figured maybe a piece of ice or something had plugged the line, (we've had warm cold warm cold weather for a week and this was the first below zero night in a week). Without writing a novel here, the car eventually started on its own but idled very rough and tries to die if left at an idle. At high rpm the engine runs perfectly. I let it idle for a good 20minutes or so and the idle became normal and leveled out at 800rpm. I turned the car of and again, it wouldn't start.

I learned quickly that the TBI isn't spraying any fuel as I crank. So I grabbed a gatorade bottle full of fuel and just give it a small squirt everytime I need to start the car.... It still surges when idling, like it tries to die but the computer saves it.... The TBI seems to be tripping out during those moments...

So the car runs if i 'prime' the throttle body, and it stalls easily at low rpm... I havn't yet checked the fuel pressure, but i have put my headf against the fuel tanka nd can hear the pump running clear as day. There is no irregularity in the sound and while the engine surges, the pump ha sno surge in sound...

I'm thinking this is a TBI/electric problem. I have reset the computer and checked the timing. I also gave the TBI a good spray of injector cleaner, and have run two bottles of fuel system/injection cleaner through the tank....

Pressure test tomorrow, but what else can i try, or check? I'll also change the fuel filter incase it picked up some debris... Though I changed it just 500km ago.

 

I would toss a fuel filter on it for obvious reasons. When you ran the tank dry there is no telling what junk you pulled up. Most of it is probably in the strainer though. The other GOOD possibility is you killed the pump. I bet you will find that you have no more than 7 PSI of fuel pressure. I would be ready to change the pump especially if it has any miles on it to speak of.

 

That's what I'm thinking I'll have to do. The weirdness is how well the engine runs at rpm.. If the pump was the problem, wouldn't the engine have troubles running at WOT down the highway? The car accelerates like normal.

Also, the sound thing. I can heare the pump running, it sound sliek any other electric pump i've used... eeeerrrrrrrrr. Steady, level sound wiht no spikes, pulses or anything. I will check the pressure and change the filter though.

Other than that, any electronic things I might want to check?

 

Not really anything that sticks out. Perhaps the ECM is calibrated richly enough for normal PE even with the lower than normal fuel pressure. GM PE schemes can be very rich. When the pump went south on my 2.8 jimmy the truck had more power than ever @ WOT, but couldn't accelerate through a wet paper towl at part throttle. Fuel pressure was at 6 psi, IIRC. When I got into datalogging the system and running a wideband on it, with the properly functioning fuel system and a mild Crane Cam, ported heads, and headers, it was still running at 10.5:1 a/f mixtures.

 

Alright guys, thanks for the replies so far, but i'm going to need osme more help if you dont mind. NOne of the mechanics at work have a fuel pressure guage or tester, neither does Canadian Tire or Princess Auto... I replaced the fuel filter today and the engine does the exact same stuff.

Won't start on its own. (need to put fuel in the TBI)

Stalls easily at low rpm. (even if I give it gas when its about to die, it just shuts down)

Doesn't have a steady idle... 800rpm for a moment then it drops to 600 or so and quickly kicks back in to 800...

The shops in town here I have looked into, charge $85-95 an hour which is about $40 bucks more than where I'm from... They don't give any advice, and just ask for you to book an appointment. I really can't afford that right now, so any advice is welcome! Please suggest anything you can think of...


Keep in mind that while I'm cranking, there is absolutely NO fuel flow from the TBI nozzles... Once in a blue moon the car will throw some fuel and start, but thats only like one out of 10 attempts. For instance, this morning it started without me putting fuel in the TBI, but not once again today did it.


Also, when it's idling, the fuel more or less drips from the TBI rather than 'misting'. Is that normal?

 

It may be possible that any trash sucked off the bottom of the tank may have made it past the filter and now your injectors are plugged up.

 

Both injectors have even spray and both 'stutter' at the exact same time. It's pulsating effect.. even idle for about 5 seconds, then it trips and kicks back in. over and over and over.

 

If I were you I'd replace the injector on the throttle body, since its not spraying and you say you hear the fuel pump priming when you turn the key on.

 

Injectors... not one. If the car runs at anything better than an idle, do you really think the injectors are shot, and both of them to boot?

 

Ah crap, eh... I bought a TBI rebuild kit. Took the TBI apart so carefully and cleaned every little part, replaced all the o-rings, filters etc... put it back together just as carefully and then I get happy with the wrench putting one of the fuel lines in and pop, the plenum brakes.

 

Thats a very common problem. I usually just tighten them just enough so they seal and are snug so it doesnt press teh threaded portion away from the rest of the pod.

Have you checked the module yet? Loss of reference pulses will do exactly what you describe. If it is indeed the module, then replacing the module and cleaning all the contact points that comprise the ground path (dist. base, clamp, and portion of intake manifold that the clamp bolts to) will make a huge difference in how the car runs.

 

Nah, I broke the TBI... $434 for a new rebuilt before the including a core exchange, so forget it.

I'm going to buy an 05 colorado. The Firebird is done.

 

Yeah, that whole wopping $20 for the pod from the junk yard will really break the bank. Same for that $35 module... Might as well just buy a new car.

 

Yeah seriuosly, you're going to call the car "done" just because you broke an extremely common junkyard part that'd cost at MOST 20 bucks?

 

The problems you are having are minor, and are to be expected with an old car. The fix in this case is likely to be relatively simple.

At least you dont have my car. For me, those problems dont even register on my radar. Theyre daily routine malfunctions with my car. Usually blowing another transmission, trashing another rear end, etc. are normal run of the mill breakdowns for me, and usually dont require a tow truck since the car will usually still move. Having the car burst into flames quantifies as an actual breakdown, as itll burn up lots of stuff and require me to come back and reroute some temperary wiring or some other patch to get the car home.

Now, running the car into a ditch, flipping it over 10 times and having it explode would be a major problem, and would likely send me reaching for my AAA card, if I was still alive.

Just remember, with any car, it can get ALOT worse.

 

The thing is, I just moved to alberta. So in order for me to have in insured here, I need the horn/airbag fixed, the windshield replaced and the engine needs to work. So, even if I found the part, rebuilt the TBI and put it back in the car, I still need to figure out why it wont start and why it wont idle. It may be a $50 dollar module, ir may not. My knowledge of how to repaird fuel injected cars is minimal and it's -18 celcius outside right now. Lets say I did fix the car for about another $1000 bucks after the windshield, horn/airbag and whatnot, it's still a beater firebird that is going to need to survive -30C weather and snow for the rest of the winter. I need AWD/4WD, not Friechicken moneyhole... The transmission is going too. So there IS more to the story than a broken TBI. Lets just say that unless I'm forced to do so, I'm not looking to repair it at this time...

I don't have wheels to be going around to wreckers in a city i'm new to anyway.

 

I have have the same problem on my 89 RS.

I rebuilt the TBI a few months ago and I as well cracked the fuel line casting. 70 bucks for a complete TBI at the junk yard.

The car ran fine for a few months. It is now doing the same thing.

Can you please clarify:

Have you checked the module yet? Loss of reference pulses will do exactly what you describe. If it is indeed the module, then replacing the module and cleaning all the contact points that comprise the ground path (dist. base, clamp, and portion of intake manifold that the clamp bolts to) will make a huge difference in how the car runs

I am not sure what module you are speaking of.