I am pretty sure that you all are tired of hearing this. Guess what? My car won't start. I have an 89 camaro RS 305 TBI. I checked the plugs and they are fine. The engine does turn over but does not fire. I sprayed ether into the tbi and it ran(kind of) until the ether was gone. I bypassed vats already. My father in law said that there is a sensor in the driver door that was corroded and it acted like this before. Has anyone ever heard of this before. If so what does the sensor look like or where in the door is it? It sounds like it isn't getting any fuel to me. How would I go about checking this? Money is tight so I can't spend a lot. I am pretty much lost. Any help would be appreciated. Right now I am going to atart all over and check everything again. I just don't really know where to start.

 

I never heard of, or seen any sensor in the door.

Is the fuel pump running? Place ear on hump in rear hatch and listen while someone else turns on key - you should hear it prime for 2 seconds. Do it at night, on a quiet street - they aren't real loud and hard to hear.

Let us know.

 

Is there another hum that can go off when I turn the key that is louder? What if I shorted out the two terminals on the aldl terminal? Also is there a way to check the pump if I dropped the tank. All in all it really isn't that complicated. I probably should anyways just to make sure that the float is ok. I messed something up with that when I tried to siphon out the gas when I first got it.The fuel gauge says it is full. The most that could be in there is 2 gallons. I just wish I knew more about cars.

 

Dropping the tank is a hard job - I'd avoid it for now if I could. Just try and listen for the pump - make sure the A/C switch is in OFF position (to keep the electric fan from coming on) - nothing else will make noise (except the key buzzer).

If you don't hear it, then we'll try a few more things BEFORE we drop the tank - there's 2-3 things that can make the pump not run that we can try.

Maybe a fill-up will "float" the float back into line - so let's worry about the pump and if it works before we worry about the guage.

 

Its the pump. Thats why it runs when you spray ether down the throttle body. I would spray gas down as engines were made to run on gas and not ether.

 

Just because its a lack of fuel doesnt mean that its 100% the pump. Could be any of the wiring or relays that run the pump...


But yea, be easy on the ether. gas engines + ether = not good stuff!

 

It could be the fuel pump relay, or the oil pressure sending unit - that's why I want to know if the pump runs at all first. If it doesn't run, then we'll do some things to see if we can get it to run BEFORE we drop the tank for no reason.

 

OK. So here we go. I applied battery voltage to the fuel pump terminal on the diagnostic port and had my wife verify that I wasn't hearing things. The pump did come on. What do I do next?

 

Sounds like the relay. Usually thats what goes on these, but the VATS system also tells the compy when to engage the fuel pump...but you said that was overridden right? A fuel pump relay shouldnt be more than 20 bucks...

 

This tells us that the relay works - since you jumped it, sending signal to ECM to run pump (which it does through the relay).

So - must be oil pressure sending unit (which is more often the cause of no fuel than anything else I see on here). Get under car, and just above oil filter there should be the oil pressure sending unit - it's about 4 inches long, and has a 3 wire connector on it. Make sure the connector is on, and not corroded. If it's off, or corroded, clean connector and put it back on, and see if that makes car run. If not, then must be bad - replace it.

It's $30 at Napa or Carquest - NO AUTOZONE OR ADVANCE AUTO PARTS - they don't even last a month!

 

OK. Here we go again. I cleaned the connection to the oil pressure sensor like you said to newbie. However I have a slight problem. When I go to reconnect the plug I disconntect it again to check it and there is oil on the bottom prong of the plug. I have cleaned out the male part of the plug as well and it keeps happening. There was quite a bit of grime on the outside of the plug. That took forever to clean off. Thank you all for your help. I really appreciate it. By the way if the sensor is bad does anyone know what size wrench to use to replace it?

 

Sorry about that misdiagnosis...guess I mixed up circuit path in my head. Confused where you were feeding the power...

 

If there's oil leaking through the OPSU, then I'd assume it's bad and I'd just replace it. It's more than likely the culprit for the lack of fuel.

 

Will I have to drain the oil to replace that sensor? I am going to buy the part after I get paid on the 13th. I guess I am stuck until then.

 

No need to drain oil - all the oil is in the pan and filter after about 10 minutes of it not running - if more than a few drops comes out there - you have way too much oil in it.

 

OK. I removed the sensor and cleaned it up completely. Reinstalled it it still did not start. I am going to buy a new opsu when NAPA opens up on Monday. I just hope that they give me the right part. The pictures on the website doesn't really look like the one that I have. Let alone there are two on their website. Does anybody have a part number for the opsu. I guess the best route to go is to take the opsu I have with me when I buy it huh?

 

Ok. Here we go again. Just an update. The part is ordered from napa and will arrive tomorrow. Will install tomorrow. Thanks again for all of y'alls help. I will update after it is installed.

 

My prayers are with ya on the OPSU,,just had to replace my fuel pump last weekend,,,full tank of gas, blazing hot sun in the parking lot at work..I wouldnt wish that on even a FORD driver

 

did you check all of the fuses? When I changed my fuel filter, i had to take out both of my... tbi? fuses so the car would stop (running out of gas on purpose... releave pressure). Check the fuses for those too, just in case

 

Did anyone recommend checking to see if the injectors were pulsing?? Could be bad injectors that are not working seeing as a TBI car does have injectors. If the OPSU doesn't fix it check your injectors to see if that click when you are cranking the car, a long screw driver with your ear on one end pushed up against the injectors works wonders!!

 

ok. I replaced the oil pressure sensor switch that was bought from napa and it it still does not start. What am I supposed to listen for on the injectors? I am still not getting fuel. I am getting mad. And feeling lost. I checked the fuses under the dash on the drivers side(all of them) and they are all good. I verified the fuel pump is still good by applying battery voltage to the fuel pump terminal on the aldl. What next? Thanks to everyone for your time and assistance.

 

put a noid light on each of the injector terminals and make sure you have pulse

 

I do not have a noid light. Is there another way to check the injectors? Can i fabricate a noid light?

 

yes you can all a noid light does is use the positive side that is always hot on the injector and the pulsed ground that starts in the computer.

a noid light is cheap at the zone and whatnot but you could make yourown with a 2 terminal lightbulb

me personally I would buy it and return it and take the module out of my dissy and have it checked at the same time

 

you said your plugs are fine, but have you checked for actuall spark?

like many people have said before, an engine needs 3 key engrediants to run: fuel, compression, and spark.

It could be as simple as a bad ignition control module or something ignition related.

Check to see if you have spark.

 

I have spark. That was verified after I installed the new cap and rotor and replaced all of the spark plugs.

 

do what everyone else has said and change the oil pressure sending unit, if that doesnt work then we can try other diagnostic things.

 

I changed the oil pressure sending unit with no change. I hooked up a noid light that I made myself and I received electrical signal to the injectors. Still nothing. Where does the fuel pump sit inside the tank? The reaon that I ask is because I am thinking that the fuel in the tank is not reaching the pump. I was wondering how much has top be in the tank for it to actually pump the fuel. I do not know how much is actually in there because the gauge says it is full. I know that it is not anywhere near full.

 

may not be youre problem but my 91 rs did the same thing i jumped the gray prime wire too a 12vlt source it started before the relay important to no location we found out the prime wire broke above the tank

 

so you are saying that it might be out of gas

if you have someone turn the key and you listen to the bottom of the tank do you hear a buzzing

disconnect your fuel line and see what you have with the key in the on position.

 

I have no spark on mine -- car ran fine last week, turns over with no spark, i can hear the fuel pump running when i turn the key - computer codes just flash 12 - -but the battery was unhooked since my oil pressure relay is bad and fuel pump would keep running - - what do i need to check? 89 Trans AM TBI

 

Anybody have any ideas on where to go. I almost have the fuel tank dropped. All I have left is to remove the rear stabilizer bar and the fuel tank retaining straps. I am thinking the fuel pump strainer is clogged or the fuel is not reaching the pump.

 

just make sure the primewire is not broken. i beleive a design flaw gm made the wires just a little short they didnt compasate for rearend movment

 

Have you disconnected the fuel line at the TBI to see if gas is actually going there? If no, but the pump runs - then maybe clogged fuel filter or pump pickup.

Have you put 2 gallons of gas in it to make sure it had gas? I'd do that before I dropped the tank - 2 gallons = 16 pounds - won't make much difference if tank does need dropped.

Have you looked to see if the injectors are shooting gas when trying to crank - I think you should be able to see some gas shooting from injectors.

Have you installed a fuel pressure guage to see what the fuel pressure is? These are $10 for el cheapo at Advance/Autozone and can be installed in the rubber part of the fuel line, driver side fenderwell.

If you are dropping the tank anyways, go ahead and replace the fuel pump and pick up screen - whether it works or not, and save yourself from dropping the tank again.

 

Thanks again. I am going to finish the tank drop tomorrow. I didn't get home from work until 5pm. I normally get home around 2pm. Anyways, I put a little over two gallons of fuel in it with no change. I am going to have to find the prime wire to verify it isn't broken. I also have to buy a fuel pressure gauge to test that. If I have forgotten anything I am sorry. I will check everything that is posted here(within reason). Will update tomorrow.

 

gl bro thats all i can think of and ty let me no it was a nightmare to locate
ps the wires on the top its the gray on mine it runs through a gromitt behind the rear seat

 

Ok. Here is the update. I pulled the gas tank. While trying to unbolt the passenger side sway bar from the frame the bolt broke at the start of the threads. Oh well. Only one bolt broke on a 27 year old car. Not bad. Anyways, I removed the tank and removed the fuel pump assembly from the car. Sure enough the problem was in the tank. If you have pulled your tank then you know that the fuel gets sucked up by the pump through the strainer into and through the pump. It then travels through a rubber hose and into the fuel line. The rubber hose had pretty much died. It had a split right in the middle of the hose. When I took it off it completely fell apart. I have to get some rubber hose to fix it. Oh and another bolt kit so I can put it all back together. I found that the bolt kit is about half the price for one side at the dealer than at Autozone. What a surprise. Thanks again.