Refresh 1982 crossfire vette

[jac1892]

It ran better with the old E.C.M. a chip,not great, but better than the with E.B.L.

 

[Maniacmechanic1]

It ran better with the old E.C.M. a chip,not great, but better than the with E.B.L.

IF YOUR NOT A COMPUTER WIZ I.T. PERSON OLD EFI SYSTEMS TO TUNE ARE NOT USER FRIENDLY.
MODERN EFI TUNERS WILL NOT EVEN TOUCH EARLY EFI NO MORE.

ONLY 1996 LT1- LT4.
GM CHEVY TRUCK 1996-1999 SBC.
1997 UP IS ALL LS.
THEY MAKE ALL LS SWAP SO THEY CAN EFI TUNE IT.
DON'T KNOW EITHER ON OLD STUFF EFI TUNE.
I worked in a Race shop.
Chassis Dyno and 3 Master EFI tuners.
They looked at my 87 Corvette and said Let's LS3 Swap it so We can tune it for You !

 

[Loves302Chevy]

 

[Maniacmechanic1]

Did You Set The Battery Offset table to begin with and had the vehicle battery fully charged 100% ?
Did you set the Injector Offset rate in Milliseconds correct ?
Most important initial EFI setup 101.

If not done never get your car tuned correct .

Battery Offset must be checked again with engine running and alternator charging.
Need 13.6-14.4 V DC the computer reads back to You.

 

[jac1892]

Question guys, I'm still wrestling with this EBL flash in the malfunction code what does IAT LO mean I have the first on three lights flashing the middle green and the last solid yellow. Next what do I do to fix it. Then EST third light is on solid yellow. and how do I fix, plus what does it mean...thanks guys

 

[Maniacmechanic1]

Question guys, I'm still wrestling with this EBL flash in the malfunction code what does IAT LO mean I have the first on three lights flashing the middle green and the last solid yellow. Next what do I do to fix it. Then EST third light is on solid yellow. and how do I fix, plus what does it mean...thanks guys

IAT Low means the Air Intake Tempature sensor is not working.
It's a 2 wire sensor or Thermistor.
It could be left unplugged yet by accident.
Faulty sensor.
No +5 vdc signal voltage to it.
No outlet sensor voltage present back to the ECM computer.

 

[Maniacmechanic1]

Question guys, I'm still wrestling with this EBL flash in the malfunction code what does IAT LO mean I have the first on three lights flashing the middle green and the last solid yellow. Next what do I do to fix it. Then EST third light is on solid yellow. and how do I fix, plus what does it mean...thanks guys

EST is electronic spark timing control.
I am not familiar with EBL.
Sorry.

 

[Maniacmechanic1]

The early GM EST Electronic spark control is unique for parts I recall.
Came about 1976 or 1978 On the Buick Centurion or Regal with the Turbocharged Buick V6.
Also used on 1981 Trans Am with Turbo 301 engine.
Used on Last of C3 Corvettes also like yours.
Have to Google read.
May be on Grumpys archives . He snatched saved forum data posts.

 

[jac1892]

Guys, thanks, the knock sensor keeps counting and runs like crap any Ideas???

 

[Maniacmechanic1]

Guys, thanks, the knock sensor keeps counting and runs like crap any Ideas???

Yes. Bypass disconnect.
Shut it off with your EBL tuning software the Knock sensor.
I recall my friend Marc had similar issues with his 1982 Crossfire Renegade Intake C3 Corvette.
He is no.longer here on Grumpys.
He knew EBL.
He is on FB only now doing his own thing.

Have to read the spark plugs old school to check for tune detonation.
It's still 100 percent accurate that way.
Also buy and install a Wide Band O2 Oxygen sensor.

 

[jac1892]

Guys I have gas fouled plug, how do I fix it? Different heat range plug?

 

[Grumpy]

please post clear pictures of the fouled spark plus pictures of the other 7 plugs,
its valuable information related to what the engines doing

 

[Maniacmechanic1]

Guys I have gas fouled plug, how do I fix it? Different heat range plug?

Sounds silly but check for a hot spark 1st.
Pull #1 spark it wire off and install a spare new spark plug. Lay against Valvecover or header tube.
Crank over and make sure you have bright blue spark.
Yellow or Orange means a weak spark.

I had the Aftermarket Accel HEI Coil fail on 87 Corvette Recent. Lasted 170,000 miles.
Robbed one from an old Pontiac V8 HEI I had.
Bright blue spark again.
It was running poor erratic.
Bad ignition COIL for me.

 

[Grumpy]

Brians correct in that you should check for a good strong ignition spark,
a defective ignition wire or a defective distributor cap might be a cause.
if a new plug fouls in the same cylinder you might have a failed valve seal or piston ring,
so its generally a good idea to do a leak-down test also

http://garage.grumpysperformance.com/index.php?threads/leakdown-compression-test.881/#post-56489

http://garage.grumpysperformance.co...han-assume-you-know-answers.13217/#post-68926

http://garage.grumpysperformance.co...ouble-shooting-rebuilding-hei-ignitions.2798/

http://garage.grumpysperformance.com/index.php?threads/verifying-your-real-advance-curve.4683/

http://garage.grumpysperformance.com/index.php?threads/ignition-wire-crimp-tool.2749/

http://garage.grumpysperformance.com/index.php?threads/changing-long-over-due-spark-plugs.10404/

 

[jac1892]

 

[jac1892]

photo 1516 is cyl #3
photo 1517 is cyl #5
photo 1518 is cyl #7

photo 1519 is cyl #2
photo 1520 is cyl #4
photo 1521 is cyl# 6
photo 1522 is cyl #8

 

[Maniacmechanic1]

photo 1516 is cyl #3
photo 1517 is cyl #5
photo 1518 is cyl #7

photo 1519 is cyl #2
photo 1520 is cyl #4
photo 1521 is cyl# 6
photo 1522 is cyl #8

Yeah it looks bad.
I see one spark plug looks Bridged fouled shorted out. Had to be running real bad.
Plugs will never cleanup right.
Need a new set.
What spark plugs are they ?
RCYJ12'S Champion?
They are Ok..have used Champions. They don't like being fouled out.
They work good for Racing Champions one the tune is correct hit real clean and smooth under load with correct AFR dialed in.
Autolite equivalent works better for Rough tuning in for me or ACCEL Copper core.
NGK spark plugs excellent too, favorite of drag racers with a huge array of heat ranges ultra cold for high boost or hot heat range for street driving duty what your doing.
Application specific again.

How was the ignition spark test?
A-ok bright blue hot spark ?
Appears white in bright daylight often
Bright blue at night or lights off in garage.

Bad tune yet...
Bad knock sensor..recall that happened to Marc One time on his 1982 Crossfire Vette.
He had a hard time finding the right one.
Another possibility is the fuel pressure regulator failed.
Hole in FP diagrhram.
It the highly polished tool steel seat is scored bypasses leaking fuel.
Aftermarket made in china.
Rough machined.
Polish with 600 grit sandpaper taped to a piece of glass.
Then go 1000 grit.
Then 2000 grit.
Will be 1-2 microns or RA smooth shine like a mirror.
Hardened seat built into center of Fuel pressure diaphragm.
Had to do the same on my 87 Corvette TPI years back.
China supplied. NOS GM Part long gone.
They hate us in the USA.

 

[jac1892]

I did the ignition test it look ok. The plug is a Champion rc9yc ,r the plugs u listed a high heat range than the rc9yc's?? thanks

 

[AutoWiz]

The injectors used for crossfire do not exist any more today. They are low impedence and a relic from the dawn of electronic fuel injection. The proper iac rubber block offs to use to sync the t.b.'s don't exist anymore today. And the death of Crossfire is in the blade shafts that ride right on the aluminum housing of the t.b.'s . These shafts wear out the housing and cause uncontrollable vacuum leaks that are not stable and change. The best way forward today with a crossfire is an edlebrock intake, an hei distributor with weights and a vacuum canister hanging off of it, and either a carb with a regulator OR a fuel injection kit like the F.A.S.T. 30400-kit. The fuel injection kits are nice because they give you a nice handheld with more accurate gauges than what is in your C4 now. But they are pricey. So expensive are they that I am a baller for being able to produce this picture..



2 of those kits went into c3 corvettes. https://www.digitalcorvettes.com/forums/showthread.php?t=292602
IF YOU went with FAST efi or any efi then you could keep your distributor because you can have electronic timing control from the efi unit. Most if not all aftermarket efi kits support timing control. Just stay away from FiTech.

 

[Maniacmechanic1]

I did the ignition test it look ok. The plug is a Champion rc9yc ,r the plugs u listed a high heat range than the rc9yc's?? thanks

12's are typical used in street high performance SBC here on Grumps.
Some Entry Drag Race heads too.
Manufactures do alot of water brake Dyno testing and on Street and tracks to determine what is the best baseline spark if to use.
I am going to go searching for Marc's old thread here..lots of good info on Crossfire.
He loves his. I talk to him on Facebook and He haves a ball driving his Crossfire C3.
Hot Rod Grand Touring Corvette he built.