Hey all,

I'm relatively new to cars and this is my first project car so I need all the wisdom I can get. To get right to the point while I was driving on the highway in my 1982 Corvette CE I bought 2 months ago I suddenly lost a lot of power and it started to sputter. I pulled out on the nearest exit and my car stalled at the stop light. I limped it to the nearest parking lot by giving it gas. I then called home for support and we found that only one fuel injector was firing and the other was spraying nothing. The passenger side that was working was dumping a ton of gas and the gas mixture was super super rich. I limped it home thankfully. I gave never worked on CFI engines and I don't know where to start. If it's at all important my right head light vacuum has a leak that I temporarily fixed with tape while parts get here but I don't think that would effect the fuel spray.

Thanks in advanced!

 

Injector, wires and ECM.

Do this and you will eliminate the most common issues. Check ECM codes, test injector( you can use a 9v battery), test wiring(you can rent a test kit from autozone or use a test light).

 

Sounds good. I'll check the injector tonight. I already bought a wiring tester kit so I'll test that after if i have time. Lol balancing college a full time job a side hustle and a project car at the same time limits time but thank you!

 

Well, new to corvette maintenance and to CFI is almost a double whammy, but luckily doable. The very first thing I can suggest that would be in your favor would be to get a 82 GM Service Manual. For a car that is 38 years old, it's a MUST. Lots of good troubleshooting charts and diagrams. The next thing would be the AIM which is the corvette assembly manual...another MUST have. You can get these on eBay from time to time. If you can't find one, PM me.

The next item on the list is... Do you have a CEL? (check engine light ON)? If so, after you have the service manual, it goes through and explains how to retrieve the codes and what they are and then walks you through the steps to narrow it down and fix the issue. You should also invest in a Digital Multi Meter (DMM) if possible, since you will be working with voltages and OHMing out wires, checking your IACs and TPS sensor setting, always handy to have. ALWAYS troubleshot the first code that comes up and go from there. Do Not just randomly start replacing parts if you have multiple codes. First off, that is not how you troubleshot anything and second, it can get expensive doing it that way. If no CEL, then it's something mechanical or the ECM doesn't seem to mind what's going on or doesn't monitor that. Was the CEL flashing by chance when it started to run badly? If so, the ECM went into LIMP HOME mode and will get you there, but run like crap getting there. The injector(s) not firing could be a bad ECM and the injector driver(s) are bad, which means ECM replacement. Can also mean a harness issue and yet it could be one or both fuses in the fuse panel on drivers side marked INJ1 and INJ2, 3amp. There are too many things that could be wrong to really guess and it would be just that, a guess. So the manual is what you need to figure out what is going on and to fix it properly.

 

Hi! Thanks for the detailed reply,

I do have the service Manuel but not the auto manufacture Manuel. I will look for one. As for the CEL there was none and it wasn't flashing. I also have my neighbors multi meter (he's a good resource because he works on 80's cars at his house and has lots of tools for old ****). I'm going to check the injector itself tonight and then test the wiring. I'll keep an update of the problem. Meanwhile how do i determine if my ECM is bad?

 

Ethan Don't jump to conclusions about the ECM... they RARELY go bad....unless something attacked it in the battery compartment.

Pull up your ashtray and find the ALDL (datalink) follow the jumper wire procedure for calling up the codes....even if you don't see any...Is the #$%^ light out!?????

The front injector is the controller injector and controls the rear one......this I think is your problem....the front injector 'lost control'. Rebuild time! Old/schmootz/etc.

Assembly Line Diagnostic Link or ALDL is a proprietary on-board diagnostics system developed by General Motors before the standardization of OBD-2. .

Unkahal

 

Unfortunately that's not true, they do go bad a lot more often than you think, but his may not be bad yet.

If you have the GM service manual it tells you what to do to pull the codes. If the injector(s) are bad, buy new ones, they are not expensive. Just put a paperclip across pins A&B under the ashtray to go into code retrieve mode. Look at page 6E-25 to start.

 

I'll check everything this Saturday! Thanks for the help!

 

I'm very curious...can you explain how the front injector controls the rear one and how the front injector lost control or how it controls anything? Maybe you have the modded 82 CE injectors?

 

Quote:The front injector is the controller injector and controls the rear one......this I think is your problem....the front injector 'lost control'. Rebuild time! Old/schmootz/etc.

I'm very curious...can you explain how the front injector controls the rear one and how the front injector lost control or how it controls anything? Maybe you have the modded 82 injectors?

 

I don't have a modded TBI system....mine has 18k on it and runs like a top. The complete 'control (pressure) system' is covered very well in the SERVICE MANUAL.

However here is a 'cute' little article on the basics.

https://www.restore-an-old-car.com/1...el-system.html

unkahal

 

additionally....


Crossfire Corvettes is controlled by the computer.

Remove the air filter housing and start the car. Check that both injectors are firing at idle. If not, on the fuse box under the dash on drivers side, there are two fuses for the injectors, injector #1 and injector #2. Both are 3-amp fuses.

Or the fuel pressure regulator has debris or the fuel pressure compensator.

good luck Unkahal

 

I'd start with the fuel pressure- PUMP.

 

If it's at all important my right head light vacuum has a leak that I temporarily fixed with tape while parts get here but I don't think that would effect the fuel spray.

Shmaybe! The car has a MAF... Manifold AIR FLOW (sensor)....it's the little black box sitting near the top of the firewall in front of the driver. Huge vacuum leak...poor MAF operation.
This is one of the first designs of a MAF....most today use a hot wire and resistance in that wire....this uses manifold vacuum Diaphragm to back out a air flow calc.

End of story...Fix the vacuum leaks!

 

OK, still waiting to hear how the front injector controls the rear injector. Also, NO CFI car, 82-84 corvette, camaro, firebird or trans am has a MAF sensor, they are ALL MAP...jus sayin'. The ONLY thing that controls FP on a stock CFI motor is the rear TB via the FPR which increases the spring pressure on the bladder if you turn it in or compress it. The compensator side does nothing to do with the control of the pressure.

 

I also have this problem with the injector stopping (the front one), I placed an LED to check the current, when the injector cuts out the LED is off, so there is a problem with the power supply and no mechanical problem (I specify that the 2 injectors are new), I connected wires from the ecm to the injectors and I also connected a + 12v directly to the injectors to eliminate the problem of a faulty harness electrical... only one output has the problem (the front one), I tried to control the 2 injectors with a single output but it doesn't work... has anyone seen this problem? ? please don't ask if i replaced the fuel filter or if i filled the tank... thank you

 

Probably the ECM is bad for the injector drivers.

 

probably..... any solution for this??
the modification with an ECM of 84 is complicated??

 

The EBL is the answer for a stock motor, but you live in France.

 

I have containers leaving NY every month