I have an 88 Camaro 305 TBI, My problem started friday, when after coming home from a two hour straight drive, I stopped at a 711 and shut my car off, when I went to start it back up, it would turn but would not start, it was cold and dark, so After a freind and i tried every easy thing we could think of to get it going I finally had it towed home, i figured it had something to do with the spark so i got a new coil and dist. cap/rotor to put in, but before i did that, i tried the car and it started, not as fast as it usually does, but it started, so i drove the car for the entire day, turned it on and off several times, the next day i went out to start it up and the same thing that happened friday, happened again, the car would turn, but wouldn't fire, so i checked it for spark and the spark seems fine, i checked to see if it was getting fuel (it's a tbi, so you can just look) and nothing, so i don't beleive it's getting fuel, my main question is : what would not work for a night, then work again, then quit working again that is fuel related? like would a fuel pump do that? or would that more likely be a relay or something? whatever it is, its too cold right now for me to fix myself, but id like to figure out what the problem is before i bring it somewhere, and save myself some money. and help would be appreciated.

 

Well, I personally have never had this problem, but it sounds like a fault in either the pump, wiring, or a relay. I'm sure some of the guys on here will be able to tell you exactly what to look for.

But my bet is on the pump, it sounds like it's on it's way out.

Just my $.02, don't hold me to it

 

I also wanted to add that other than this problem the car has been fine, running at full power ect. so any kind of fuel starvation has not been apparent.

 

Since the problem is apparently intermittent, you'll have to be patient. When it happens again, listen for the fuel pump running in the tank. It should run for two seconds when the ignition is turned ON (provided the ignition has been OFF for at least 20 seconds), or whenever the distributor is sending reference pulses to the ECM.

• If the pump is not running, start by checking the relay, it's connector, power from the fuel pump/ECM fuse, and the circuit wiring.
• If the pump is running but you get no fuel spray, you may need to diagnose the injector pulses from the ECM. There are two fuses for the injectors, electrical connectors at the injectors themselves, and grounds for the harness and ECM. The ECM will also cut fuel pulses if there is no RPM signal (reference pulses) from the distributor.

 

Vader's suggestions are good. You might also want to verify that your ECM is functioning properly. Verify that you can read some codes out of it next time its in the "no fire" mode. I believe the ECM is what sends power to the Fuel Pump for 2 seconds, so if that is working the ECM is probably doing its job and is ok.

Also, if your car came with PASSKEY - VATS (I think it was optional that year) let us know. It doesn't sound like its that unless someone did some customization though.

Sometimes these intermittent problems can be really difficult to figure out. Good luck!

 

well she's completely dead now(still turns, but absolutley no luck starting), *** i wish it was summer, it's like 40 below every damn day in ma right now, it's so hard to bring myself up to go out and work on her, and to make matters worse, it's my daily driver.

 

I'm in MA also, so I know exactly how you feel!

Hopefully your home though. My car died last week at work an hour away parked behind a dark warehouse! I was under the dash checking wires until 12:30 in the AM due to a VATS failure. Needless to say, everyone thinks I'm nuts!

- joe

 

Well I had the same intermittent symptons with a firebird. it wound up being a faulty ignition module. damn thing would always seem to stop working whenever I was in a rush, far from home or snowy/rainy days. replaced the module and never had the problems again.

 

Okay, well I think I would like to change the fuel relay(s?) but I know less than nothing about the fuel systems on third gens, where the **** are they on these things?

 

haha, still can't get this problem killed, i scanned the aldl and got a code 42 and a code 44, 42 having something to do with the spark timing (which I belive to be fine because it starts up with starter fluid dumped into the tb, I may have gotten this a long time ago and forgot to clear it) and 44 being a lean mixture (duh) but I dunno, just wondering if anyone else had simular codes when a relay / pump / ect. died???

 

I have a simular problem. Mine is an 1988 and I have no voltage at the orange wire at the fuel pump relay. The wiring diagram lists hot at all times and a 20 amp inline fuse. If I jumper the orange wire to the battery at the relay the car has power. I checked all the fuse links at the battery and the starter. All test ok. Anyone know where this 20 fuse is?

 

Found the fuse. Next to battery. Car wont start sometimes, so I jump the fump pump at the aldl connector and pound on the floor above the rear axle the fuel pump kicks in and the car will then start. Time to go fuel pump shopping.

Josh1988 your problem is most likey the same as mine, A bad fuel pump.

 

thats exactly what it was, i actually figured this problem out a couples days ago when a freind suggested i beat the **** out of the fuel tank to see if i could get the pump spinning and it worked enough to allow me to drive it to my mechanic,as its WAY too ****ing cold around here right now to do anything myself.(no garage)

 

Wow, you guys have my sympathy. Cold, holidays, and a failing fuel pump! Not a nice combination.

Good trick on diagnosing the fuel pump, I hadn't heard of that one.

I did a fuel pump on my car last year with the help of a friend. It turned out the job was a real bear. The fuel pump is definitely not designed for convenient access on these cars.

 

The way around that is to cut a door in above the fuel tank so you can get at it from the inside of the car... I'd like to find an instructional file from someone who has done this before because I know it has been done. This would be perfect, at least for me, in my iroc because it's completely gutted, so i wouldn't even have to lift carpeting:lala: Im not even gonna bother in my 305 as, obviously, i just did it and i probably won't have the car by the time that thing dies again, and then it's someone elses problem.

BTW, have you seen the prices on sending units for these things? wtf is with that? fortunatley, mine was still good, but my mechanic told me that often times the sending units are trash and need to be replaced along with the pump, the cheapest one i found was like 250 and that was online, but I've seen them as high as 450.

 

You have to cut a square above the tank then cut the front slope out to the shock tower on the left side the car. Really F's up the car. I would not do it. It's a one day job to drop the tank.

See here for damage!!!

 

I'm not a supporter of cutting out the floor/body panels either. The steel hoses coming out of the sending unit are pretty long and a lot of cutting will have to be done.

Not to mention, you have to question the safety of driving around with nothing more than a metal flap protecting the passengers from the gas tank.

By the time your done, I'm not sure how much easier it will actually be taking the butchers approach.

- joe

 

I am fairly new to this forum, and I know this is a quite dated post, but I have had the same issues with my 88 camaro 305 TBI, it worked fine, then it would stall out and not start until a few hours later, then would start again, until one day it would not start at all. I have thus far in the two years since changed the fuel pump, the fuel filter, the distributor cap, plugs and wires, router, the distributor sensor, the throttle position sensor, the ECM, the throttle body itself, and still nothing. fuel is getting through the lines, but not spraying into the ports through the injectors. I have put injector cleaner in along with new fuel, new oil, and still nothing. if ANYBODY at all happens to see this and has any insight on the situation please HELP ME before I drop anymore money on it to no avail

 

Since you have already thrown most of the kitchen sink at it I will ask two questions. Does it have spark at the spark plugs and did you test the fuel pressure (is it within spec) or just see that there is fuel being delivered?

 

it gets spark, turns over, and fuel is getting through the lines fine, and in two different throttle bodies, not getting through the injectors, even with one of the throttle bodies thoroughly cleaned, are there any other sensors that could be the issue besides the tps and the map sensor?

 

Ok i havent read everyone elses posts just yet but, just one quick question, does your key have a resistance chip on it? if so the chip could be going bad, or it has to do with the Ignition system?

 

nope, no chip on the old 88, just good old fashion metal

 

have you tried a new or used ignition module,check ecm fuse also

 

replaced the ignition control module with a brand new one, and all fuses are good. still no dice, all the best mechanics i know, even those who specialize in camaros in particular are stumped by the results after all this

 

Back to fuel pressure. Did you check it with a gauge? I have seen the regulator fail and the fuel pressure go so high that the injectors can not over come the pressure to open. This was on TPI cars but I would assume it could also happen on a TBI also.

 

tps sticking(high voltage),high resistance in coolant temp sensor or sensor it self,water contaminated fuel,egr operation,ignition system(short on wires,proper outputpick up coil),faulty in tank fuel pump or fuel pressure(fuel pressure regulator)