Help with 84 crossfire
Thread Starter
Instructor
Joined: Jul 2013
Posts: 217
Likes: 0
From: Hoxie Kansas
Help with 84 crossfire
84 crossfire with 85k on it, auto
Motor idles rough, smells very gasy, when pushing on the throttle it dies or back fires on top the motor through the throttle bodies.
Car does smell like it has some old gas. Add some new gas.
Check the timing and it is perfect.
It does not look like the spray pattern for the gas is correct. But I am not sure. I watch a video on youtube and this one does not look like that one did.
The fan runs all the time when car is running. Where the relay for the fan is it looks like the wires have been cut and put back together. Their is a a spot where their are 2 wires going to only one.
Up front their are a few wires broke. They are for the cruse. That should be an easy fix. Does the cruse use vacuum?
I do have a vacuum line that I do not know where it goes. Its on the drivers side and up front toward the bumper it has a T in it and runs to the back of the motor.
thanks again for any help
Motor idles rough, smells very gasy, when pushing on the throttle it dies or back fires on top the motor through the throttle bodies.
Car does smell like it has some old gas. Add some new gas.
Check the timing and it is perfect.
It does not look like the spray pattern for the gas is correct. But I am not sure. I watch a video on youtube and this one does not look like that one did.
The fan runs all the time when car is running. Where the relay for the fan is it looks like the wires have been cut and put back together. Their is a a spot where their are 2 wires going to only one.
Up front their are a few wires broke. They are for the cruse. That should be an easy fix. Does the cruse use vacuum?
I do have a vacuum line that I do not know where it goes. Its on the drivers side and up front toward the bumper it has a T in it and runs to the back of the motor.
thanks again for any help
Last edited by wendal; Dec 21, 2013 at 08:00 PM.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
Just adding fresh gas to old gas does not work. The fuel needs to be all fresh.
You have to post photo's of what you see.
Checking the fuel pressure requires a special set-up and adjusting the fuel pressure requires a special tool and removing the plate that prevents you from adjusting the fuel pressure that the factory installed.
Your open vacuum line can be causing much of this. If more un-metered air gets into the system...then the fuel will be added causing it to run really rich. And like you suspect..if the fuel pressure is low...the idle can be rough if not go up and down and "hunt" for a smooth idle...which it will not be able to do.
DUB
You have to post photo's of what you see.
Checking the fuel pressure requires a special set-up and adjusting the fuel pressure requires a special tool and removing the plate that prevents you from adjusting the fuel pressure that the factory installed.
Your open vacuum line can be causing much of this. If more un-metered air gets into the system...then the fuel will be added causing it to run really rich. And like you suspect..if the fuel pressure is low...the idle can be rough if not go up and down and "hunt" for a smooth idle...which it will not be able to do.
DUB
Pro
Joined: Sep 2012
Posts: 610
Likes: 12
From: Seattle Wa
The throttle shafts are notorious for going bad on these cars. (Mine are, as we speak) To check them, grab ahold of one side, and try, and wiggle it. If it moves, they're bad. Also try checking/setting your TPS.
The vacuum line, if attached to the motor, needs to go somewhere, or be plugged if its sucking air. May be for emissions, that someone halfway removed. If thats the case, its a good idea to replace the PCV valve with an L shape, instead of the T. Depending on what all has been disconnected, you could be getting a leak at the vacuum canister. Using an L eliminates this, and other problems. h
The vacuum line, if attached to the motor, needs to go somewhere, or be plugged if its sucking air. May be for emissions, that someone halfway removed. If thats the case, its a good idea to replace the PCV valve with an L shape, instead of the T. Depending on what all has been disconnected, you could be getting a leak at the vacuum canister. Using an L eliminates this, and other problems. h
Racer
Joined: Aug 2013
Posts: 301
Likes: 0
When you checked the timing, did you unplug the est connector?(single wire connector between the brake booster and the wiper motor) If not - you will have set the timing too low. Just leaking at the throttle shafts shouldn't make it run that badly, although being out of sync will make the idle funky. The cooling fans on the 84 are not controlled by the ecm, there is a temp "switch" in the passenger side head and a pressure switch on the back of the a/c compressor that turns on the relay. Sounds like someone hooked the wires together so it runs anytime the key is on. It's an easy fix, and will keep your fan from wearing out prematurely. If everything else checks out ok, you may need to verify that the outer ring on the harmonic balancer has not slipped on the inner, making your timing mark off. I remember seeing a post showing that the mark should line up with the edge of one of the three "arms" on the center section, but can't remember who posted it.(had a picture)
Burning Brakes
Joined: Feb 2013
Posts: 1,173
Likes: 152
From: norway
When you checked the timing, did you unplug the est connector?(single wire connector between the brake booster and the wiper motor) If not - you will have set the timing too low. Just leaking at the throttle shafts shouldn't make it run that badly, although being out of sync will make the idle funky. The cooling fans on the 84 are not controlled by the ecm, there is a temp "switch" in the passenger side head and a pressure switch on the back of the a/c compressor that turns on the relay. Sounds like someone hooked the wires together so it runs anytime the key is on. It's an easy fix, and will keep your fan from wearing out prematurely. If everything else checks out ok, you may need to verify that the outer ring on the harmonic balancer has not slipped on the inner, making your timing mark off. I remember seeing a post showing that the mark should line up with the edge of one of the three "arms" on the center section, but can't remember who posted it.(had a picture)
Burning Brakes
Joined: Feb 2013
Posts: 1,173
Likes: 152
From: norway
84 crossfire with 85k on it, auto
Motor idles rough, smells very gasy, when pushing on the throttle it dies or back fires on top the motor through the throttle bodies.
Car does smell like it has some old gas. Add some new gas.
Check the timing and it is perfect.
It does not look like the spray pattern for the gas is correct. But I am not sure. I watch a video on youtube and this one does not look like that one did.
The fan runs all the time when car is running. Where the relay for the fan is it looks like the wires have been cut and put back together. Their is a a spot where their are 2 wires going to only one.
Up front their are a few wires broke. They are for the cruse. That should be an easy fix. Does the cruse use vacuum?
I do have a vacuum line that I do not know where it goes. Its on the drivers side and up front toward the bumper it has a T in it and runs to the back of the motor.
thanks again for any help
Motor idles rough, smells very gasy, when pushing on the throttle it dies or back fires on top the motor through the throttle bodies.
Car does smell like it has some old gas. Add some new gas.
Check the timing and it is perfect.
It does not look like the spray pattern for the gas is correct. But I am not sure. I watch a video on youtube and this one does not look like that one did.
The fan runs all the time when car is running. Where the relay for the fan is it looks like the wires have been cut and put back together. Their is a a spot where their are 2 wires going to only one.
Up front their are a few wires broke. They are for the cruse. That should be an easy fix. Does the cruse use vacuum?
I do have a vacuum line that I do not know where it goes. Its on the drivers side and up front toward the bumper it has a T in it and runs to the back of the motor.
thanks again for any help
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Burning Brakes
Joined: Feb 2013
Posts: 1,173
Likes: 152
From: norway
Thread Starter
Instructor
Joined: Jul 2013
Posts: 217
Likes: 0
From: Hoxie Kansas
thanks for the help guys.
I will do some looking.
I did unplug a brown wire that had a white stripe on it. I was on the drivers side by the distributor. When plugged in it read about 8 degrees and when unplugged it was right on 6 degrees.
I was a bit confused on the vacuum line.
Does the cruse use vacuum?
I will do some looking.
I did unplug a brown wire that had a white stripe on it. I was on the drivers side by the distributor. When plugged in it read about 8 degrees and when unplugged it was right on 6 degrees.
I was a bit confused on the vacuum line.
Does the cruse use vacuum?
Thread Starter
Instructor
Joined: Jul 2013
Posts: 217
Likes: 0
From: Hoxie Kansas
I am not sure but I can not find where the cruse vacuum goes. The line goes from the unit above the battery then has a T, goes to the front the the motor with one side and Ts again. I think one side goes in to the cruse box in the bumper. Going back to the first T, the line going back to the motor. Where does it go? I can not seem to find any where to plug it in.
thanks again
thanks again
Burning Brakes
Joined: Feb 2013
Posts: 1,173
Likes: 152
From: norway
Racer
Joined: Aug 2013
Posts: 301
Likes: 0
On the cruise control vacuum, one vacuum line will go from the cruise control servo to the vacuum release switch on the brake pedal, and the other will hook to a "T" fitting, with one of the lines going to a vacuum accumulator (black plastic ball below driver's side headlight, and the other line will connect to the engine vacuum with a one-way check valve between the engine and the "T"
http://s790.photobucket.com/user/***...acuum.jpg.html
http://s790.photobucket.com/user/***...acuum.jpg.html
Racer
Joined: Aug 2013
Posts: 301
Likes: 0
This shows the cruise servo mounted below the headlight, but mine was mounted above the battery
http://s790.photobucket.com/user/***...ayout.jpg.html
http://s790.photobucket.com/user/***...ayout.jpg.html
Thread Starter
Instructor
Joined: Jul 2013
Posts: 217
Likes: 0
From: Hoxie Kansas
I am thinking that the cruse vacuum line goes to the can in the pumper and the round ball should go up their too. The other line I think is the one that goes to the break peddle?