1984 crossfire problem-diesels after shutoff
Thread Starter
3rd Gear
Joined: Nov 2008
Posts: 3
Likes: 0
1984 crossfire problem-diesels after shutoff
Help! I have an 84 with crossfire injection that diesels when it is shut off. The problem seems to be worse when the engine is cold, but still does it a little when warm. I have put in new injectors and regulators and still n o change. I installed a new ignition switch(it needed one, as the previous owner installed a secondary switch since the key switch wouldn't start it. I do know that the fan switch(between the six and eight cylinders) has been jumped out so that the fan runs all of the time. Does this send a signal to the ecm to control the fuel injectors? Any help would be appreciated.
Pro
Joined: Mar 2008
Posts: 552
Likes: 2
From: Dubuque Iowa
Could be a problem with your timing, but I will bet it has to do with here your idle is set.
It happens more when it is cold because the idle will be higher when you first start the car (like a choke on a carb.) Lower your idle and see how the engine resonds.
It happens more when it is cold because the idle will be higher when you first start the car (like a choke on a carb.) Lower your idle and see how the engine resonds.
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
So how do you adjust the idle on a CFI?
Pro
Joined: Mar 2008
Posts: 552
Likes: 2
From: Dubuque Iowa
I have had similar problems on other Non CFI engines and the problem was with the engine running too fast at shut off. I lowered the idle speed and no more dieseling.
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
Ride250s
Ok, so you don't know what your talking about when telling the OP to just simply adjust his idle. Unfortunetly its not that easy. Your offering misinformation. A CFI is not a carb setup.
Just like any other fuel injection system you have a IAC,TPS,CTS,MAP which all send information back to the ecm which in turn calculates the A/F and sends that info back to the injectors. This is where you get your idle from.
How do you adjust the idle on your 87?
Anyways to the OP
What is your RPM at cold start Idle?
RPM when warmed up?
According to the FSM if an engine is dieseling it may be due to leaky injectors or ignition switch. Seems the switch was already replaced.
Have you observed the spray from the injectors while the car is running? As you turn it off?
When you had the Tb's apart are all the o-rings / gaskets seated back properly? Have you observed fuel pressure?
Whens the last time you balanced the TB's?
I know a lot of questions but that information will help you find your answer sooner.
Ok, so you don't know what your talking about when telling the OP to just simply adjust his idle. Unfortunetly its not that easy. Your offering misinformation. A CFI is not a carb setup.
Just like any other fuel injection system you have a IAC,TPS,CTS,MAP which all send information back to the ecm which in turn calculates the A/F and sends that info back to the injectors. This is where you get your idle from.
How do you adjust the idle on your 87?
Anyways to the OP
What is your RPM at cold start Idle?
RPM when warmed up?
According to the FSM if an engine is dieseling it may be due to leaky injectors or ignition switch. Seems the switch was already replaced.
Have you observed the spray from the injectors while the car is running? As you turn it off?
When you had the Tb's apart are all the o-rings / gaskets seated back properly? Have you observed fuel pressure?
Whens the last time you balanced the TB's?
I know a lot of questions but that information will help you find your answer sooner.
Pro
Joined: Mar 2008
Posts: 552
Likes: 2
From: Dubuque Iowa
Ride250s
Ok, so you don't know what your talking about when telling the OP to just simply adjust his idle. Unfortunetly its not that easy. Your offering misinformation. A CFI is not a carb setup.
Just like any other fuel injection system you have a IAC,TPS,CTS,MAP which all send information back to the ecm which in turn calculates the A/F and sends that info back to the injectors. This is where you get your idle from.
How do you adjust the idle on your 87?
Anyways to the OP
What is your RPM at cold start Idle?
RPM when warmed up?
According to the FSM if an engine is dieseling it may be due to leaky injectors or ignition switch. Seems the switch was already replaced.
Have you observed the spray from the injectors while the car is running? As you turn it off?
When you had the Tb's apart are all the o-rings / gaskets seated back properly? Have you observed fuel pressure?
Whens the last time you balanced the TB's?
I know a lot of questions but that information will help you find your answer sooner.
Ok, so you don't know what your talking about when telling the OP to just simply adjust his idle. Unfortunetly its not that easy. Your offering misinformation. A CFI is not a carb setup.
Just like any other fuel injection system you have a IAC,TPS,CTS,MAP which all send information back to the ecm which in turn calculates the A/F and sends that info back to the injectors. This is where you get your idle from.
How do you adjust the idle on your 87?
Anyways to the OP
What is your RPM at cold start Idle?
RPM when warmed up?
According to the FSM if an engine is dieseling it may be due to leaky injectors or ignition switch. Seems the switch was already replaced.
Have you observed the spray from the injectors while the car is running? As you turn it off?
When you had the Tb's apart are all the o-rings / gaskets seated back properly? Have you observed fuel pressure?
Whens the last time you balanced the TB's?
I know a lot of questions but that information will help you find your answer sooner.
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Thread Starter
3rd Gear
Joined: Nov 2008
Posts: 3
Likes: 0
The timing is set at 6 btdc. The thermostatic air cleaner louvers move freely. I have yet to check if there is a vaccuum leak on the air cleaner or if the heat sensors are working or if they are even connected correctly to th louvers. I do know that the louvers are not closing when I start it up cold.