1982 cross fire injection question - Forums - Official C3 Vette Registry

SPONSOR AD

Support our Vendors! | Advertise Here

Topic: 1982 cross fire injection question

in Forum: C3 Fuel, Emission Control, and Exhaust Systems

Already a Member?
Login
Not yet a Member?
Register for Free!

1982 cross fire injection question (1/7)
10/15/06 12:58pm

1982CE
Former Member
Send Private Message

Peoria, AZ - USA

Vette(s):
1982 Collector Edition

Joined: 6/24/2004
Posts: 28

On my 1982 I replaced the O2 sensor and the engine ran better with less hesitation. After driving 3 blocks I headed home, and one block from my house (thankfully) the engine quit, and it won't start. Does anyone know how much fuel should be coming out of the Throttle body injectors when you crank the engine over? It just seems to drip down out of both of them. I sprayed a little starting fluid in each intake and the engine started for a few seconds. It is getting spark. I replaced the in line fuel filter, and it still won't start. I had replaced the electric fuel pump and strainer about 1 and 1/2 years ago. There are no trouble codes showing just 12. My question is, when cranking the engine over, how much fuel should be coming from the injectors? Should it spray out, or drip or run? Does this sound like the fuel pump again? I have a car show next weekend. Of all the times for this to happen.

Any help will be greatly appreciated.

Our Sponsors help support C3VR

1982 cross fire injection question (2/7)
10/15/06 1:57pm

Adams' Apple

Lifetime Member
Moderator
Send Private Message

Duncanville, TX - USA

Vette(s):
#1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas

Joined: 11/8/2003
Posts: 20203

There should be a definite spray while cranking. Have you checked fuel pressure?
In order for the injectors to fire, there has to be fuel pressure, oil pressure, and a RPM signal from the distributor, as well as an injector sig. from the ECM.

I would suggest checking fuel pressure first, and then for a reference pulse from the dist. If there is no fuel pressure when you first turn the key on( for 5-6 seconds), then you need to check the pump relay, and fuse.

If you have good pressure with key on, but no fuel from the injectors, then you would need to check for an injector pulse while cranking. No injector pulse is usually an ign. module failure, but not always.

No codes(only 12-system OK) doesn't really help. Even if a code had set when it died on you, turning the key off erased it.
Start with pressure, then inj. pulse.

Also, check the O2 sensor wires, since you replaced it. If the wires got pinched/damaged/melted on your short drive, it could signal a "clear flood" mode in the ECM, keeping the injectors from firing. You may need to have a scan tool hooked up to determine the cause of the failure/no start.Adams' Apple2006-10-15 14:01:16

______________

Joel Adams
C3VR Lifetime Member #56
My Link

(click for Texas-sized view!) NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

1982 cross fire injection question (3/7)
10/16/06 3:20pm

xfire
Former Member
Send Private Message

Saxonburg, PA - USA

Vette(s):
1982 Black over red, doing a resto.

Joined: 11/14/2003
Posts: 143

When you turn the key to the on position, can you hear the fuel pump running? If not, check the fuses and the fuel pump relay. It's behind the drivers seat compartment.

If you remove the aircleaner and turn the key on, you should see fuel priming the intake.

A noid light can be used to see if you have injector pulse while trying to start the engine. It plugs into one of the injector connectors.

I try this route before checking fuel pressure, the adapter for the gauge replaces the fuel filter, it's harder for old guys like me to get to!!! LOL

Hope that helps you some,

Denny

1982 cross fire injection question (4/7)
10/16/06 6:38pm

1982CE
Former Member
Send Private Message

Peoria, AZ - USA

Vette(s):
1982 Collector Edition

Joined: 6/24/2004
Posts: 28

Thanks for the replys.

I can hear the fuel pump when the key is first turned on. I don't have a fuel pressure gage. I agree, about getting under to replace the fuel filter. I did replace the oil pressure sending unit today, but still no luck. I understand the the ECM is looking for 4 pounds of oil pressure. The wire to the O2 sensor looks ok, not burned, or pinched. I think it is pluged to the car wire harness ok. I did have a hard time getting my hands under there to push it together. If it is not making contact could that cause my problem? Also could the fuel pump relay be bad, but still fire up the pump? Removing the battery, and ECM to get to the relay does not sound like fun.

I just ordered a noid light for the 82 cross fire injection. I hope it has instructions.

I'll keep you all informed.

Thanks

1982 cross fire injection question (5/7)
10/16/06 7:12pm

kstyer

Lifetime Member
Moderator
Send Private Message

CUYAHOGA FALLS, OH - USA

Vette(s):
1975 C3 Red, T-Tops, Black Interior. All I need is time and money! Getting there!

Joined: 12/2/2003
Posts: 6424

The oil pressure switch will not have any effect on the car starting, just on if it continues to run. But it will fire up. The fuel pump relay supplies power to the pump at key on and while cranking. After it's running the relay shuts off and the oil pressure switch supplied fuel pump power.

You can hear the pump so the relay is working, and you should have fuel at startup.

Try spraying a bit of starting fluid in the throttle bodies and crank the engine. Give it a several second blast in each side. If the car fires, then dies, you know for sure you have a fuel problem.

Next step is the noid light. Put in in the injector plug and crank the engine and see if it blinks. If it does you may have low fuel pressure. If not there is a computer problem, but that may not be the computer itself.

You can also put a test light across the injector connection and do the same thing as a noid light, but the noid light is easier to see.

The O2 sensor will affect the way it runs, but not the way it starts. Don't worry about it until AFTER the car is running.

Let me know what happens with the light and the starting fluid. Also check to see if you have spark to the plugs. We can fix this.

1982 cross fire injection question (6/7)
10/19/06 11:34am

1982CE
Former Member
Send Private Message

Peoria, AZ - USA

Vette(s):
1982 Collector Edition

Joined: 6/24/2004
Posts: 28

I removed the electric fuel pump, and the 2 inch rubber hose that attaches from the electric fuel pump to the gas feed line was spongy and had a hole in it. It was sending most of the gas back in the tank. I put in a new pump and hose (that was included with the pump), and it fired right up. I am wondering if the fuel injection cleaner in the tank dsteriorated the rubber. I am not going to put any injection cleaner in the gas again unless I have a full tank and run the tank down. I don't drive the car much in the hot Arizona summers, and it sat for a long time in the garage with less than a tank of gas.

Now I have to replace the 3 inch fuel line from the top of the sending unit to the fuel line. The return and vent hoses are in good shape. I hope I can do this without dropping the tank. It is a tight space to work after you remove the gas door. I am going to wait until next week for that project.

Thanks for all who responded with help. This is a great site, and I have learned a lot.

1982 cross fire injection question (7/7)
10/19/06 7:14pm

Adams' Apple

Good to hear ya got it fixed!!!
See...a pressure check would've found that!!

(Jest messin wid ya!!)
Congrats..I'm glad it wasn't something worse!! I have seen the little short hose crack, just as yours did, on several cars. The pump just pumps it's little heart out, but...it's just dumpin it back in the tank!

I doubt the injector cleaner had any effect on the hose, other than possibly being the straw that broke the camel's back. The hose was probably deteriorated to begin with, and would have failed with or without the fuel additives.

______________

Our Sponsors help support C3VR