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CrossFire tuning help needed

T

tak

Guest
Having problems with the 82 cross fire running rich. When you start it it dumps so many fumes out the exhaust it'll put you right out the garage. There are new plugs in it and the injectors are both squirting nice and even. Now there is an exhaust manifold gasket that is blown out (will be getting fixed soon), could this be throwing the computer off or is there something else I should be looking for ?

Thanks for all the help!!!
 

zachh

Well-known member
Joined
Aug 1, 2005
Messages
221
Location
virginia beach, va
Corvette
1979 black 'n' silver L82 1978 Trans Am Y88
A bad exhuast gasket would make it sound funny, and youd smell exhaust up by the engine. I dont think the computer is complex enough ( beings that its an 82) that the computer would be thrown off. My advice of things to check would be your timing (if its to far slowed it most likely wont burn all the fuel, or burn it late, which would make a smell) It would also probally run a little skiddish. Your best bet is probally the fuel pump. If its sending to much fuel, the car cant burn it all. It happened to my 79 so bad, I was driving and had pull over and take the t-tops out and stick my hed out the window. Also, i dont know much about the Crossfire Throttle Badies, but chack to make sure everything is adjusted correctly. An O2 sensoir might also be the problem.
Best Wishes
zachh
 

redvett

Well-known member
Joined
Dec 16, 2001
Messages
486
Location
AZ
Corvette
2001 Convertible
For starters fix the exhaust leak and replace the coolant sensor. The one with the black and yellow wires. It controls the ECM temp and the amount of fuel that goes to the engine.
 
T

tak

Guest
For starters fix the exhaust leak and replace the coolant sensor. The one with the black and yellow wires. It controls the ECM temp and the amount of fuel that goes to the engine.

I'll start by fixing the leak, but for everyone answering, the rich smoke is coming out the exhaust, also, it runs fairly smooth, just alot of exhaust smoke.
It doesn't appear to be oil smoke either but this weekend I'm going to check the valve seals just to be sure.

The car just really seems to be running VERY rich.

Thanks for helping!
 

tcolyer

Well-known member
Joined
Jun 4, 2002
Messages
87
Location
Springfield, TN.
Corvette
1982 Silver-Blue Coupe, 1986 4+3 Coupe
82 Crossfire

I would check oxygen sensor, coolant sensor and make sure you do not have intake leak (spray carb cleaner around top plate) Have you set the TPS voltage? If you have more troubles you can E-mail me direct @ tcolyer012@aol.com.

I have a 82 Crossfire myself & have done alot of work & modifications to it.

Terry Colyer
 
Joined
Jul 28, 2003
Messages
1,765
Location
Frankfurt/Germany
Corvette
1982 Collector Edition

Twin_Turbo

Well-known member
Joined
Jan 11, 2001
Messages
618
Location
Enschede, The Netherlands
Corvette
1982 Twin Turbocharged Red/Black
a leaking exhaust upstream of the oxygen sensor ()near cat) will create a false lean signal, that may very well be the cause of the overly rich situation.
 
T

tak

Guest
a leaking exhaust upstream of the oxygen sensor ()near cat) will create a false lean signal, that may very well be the cause of the overly rich situation.
The leak is at the exhaust manifold at the # 7 cylinder. I have noticed the wires at the coolant sensor are pulling out of the plug and have bare copper wire showing which is corroding and also the upper plenunm has oil around the 3 back bolts by the EGR vavle, and gasket lools to be leaking too. I quess I have a few spot to start at.

Any and all other suggestions still appriciated...This is my first Vette and I'll take all the help I can get with this CFI..

Thanks
 

jdp6000

Well-known member
Joined
Aug 23, 2004
Messages
646
Location
Aurora, Ontario, Canada
Corvette
1982 CROSSFIRE
Is the exhaust stock?

Sounds like you need to replace the coolant sensor. If you haven't replaced the O2 I would do that as well.

Check the EGR. Engine running push up on the diaphram...should make a change in engine idle if its working.

Jim
 
T

tak

Guest
Is the exhaust stock?

Sounds like you need to replace the coolant sensor. If you haven't replaced the O2 I would do that as well.

Check the EGR. Engine running push up on the diaphram...should make a change in engine idle if its working.

Jim
Yes, stock exhaust. EGR seems fine. I'm hoping replacing the intake gaskets and coolant sensor will fix it.
 

jdp6000

Well-known member
Joined
Aug 23, 2004
Messages
646
Location
Aurora, Ontario, Canada
Corvette
1982 CROSSFIRE
Every little bit helps. See what happens after you replace the CTS and intake gasket. Mine was doing what yours is doing. I also replaced those items among others. My problem turned out to be worn throttle plate shafts.

Keep something in mind. These cars are about air,gas, and temp. You throttle bodies are balanced from the factory at 6 inches of water (6 wg). Thats is so sensitive that you can not even detect that pressure with your finger. Imagine a small air leak in the intake gasket or throttle shafts. The O2 will pick up on that....to much air equals more gas being dumped.

You can check for throttle shaft wear. With the plates in the closed position wiggle the shafts. While wiggling the shafts place a finger on the plate, if the plate moves at all the shafts are worn. Its a common problem.

Also do yourself a favor. Don't mess with any of the settings at this time, i.e. TPS or on the TBI's.

Jim
 
T

tak

Guest
Thanks everyone on the suggestions on running problems....
Just an update, replaced the intake gaskets, timed the motor at 8* and she's running pretty good. I think it needs a new set of plugs, the fouled ones aren't cleaning up as well as I expected.
Tore the broken windshield out and found NO rust in the frame, as expected though. There isn't any in the kick panel area either. I quess it payed off when I decided to buy a rust free car over one that ran alittle better.

Tony
 

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