1996 C-4 Help!!!!
Thread Starter
6th Gear
Joined: Feb 2014
Posts: 6
Likes: 0
1996 C-4 Help!!!!
My 96 C-4 has been giving me some issues regarding stall out. My issue is last week I drove to work about 45 minutes, went to lunch and when it was time to return the engine would not start, or it trys to start and then die. I took it to the shop and consulted this forum, after which I had the ICM replaced since it was a problem that is somewhat common with this model. Today, I was experiencing this issue: The engine ran undriven for about 1 hr, I drove it to lunch and when I started it up it began doing the same thing; which is the idle which is 1000 rpm begins to dip and it gives teh impression of a stall beginning. The car runs after it starts moving but I am concern about this issue and seelk some advice as to what may be causing this issue. There are no indicator lights and there is no code for this problem.
Regard
xprtmdic
Regard
xprtmdic
Le Mans Master
Joined: Jul 2009
Posts: 6,381
Likes: 66
From: SF bay area C.A.
C4 of the Year Finalist
Have you checked your fuel pressure, when was the fuel filter replaced? I would not have suggested the icm since it didnt start cold.
Last edited by kimmer; Feb 28, 2014 at 12:58 PM.
Drifting
Joined: Mar 2012
Posts: 1,492
Likes: 61
From: New Jersey
First do you have a Factory Service manual - it is invaluable for repair and diagnosis. It has an entire section devoted to diagnostic procedures. If you already have it - go to section 6 of the engine portion of the manual for the diagnostic flow charts. Until then the following info from the manual should get you started.
At 110K miles there may be maintenance issues. First have you ever changed the oxygen sensors. The sensors are supposed to be changed at 100k. The pre-cat sensors can cause running problems.
Have you pulled the sparkplugs to check their condition. At 100k, they are due to be changed. Is the Fuel pressure regulator original. If so pull the vacuum line and check for fuel and fuel smell. Even if it is okay you should think about changing it. Are the spark plug wires original? Pull into a dark area and raise the hood to look for arcing from the wires. They may not be the problem but can contribute. Check all of the vacuum lines - they rot over time and can cause problems. Check and see if the EGR is sticking open. Check the vent lines for the opti cap - it may be a good idea to check the opti cap and rotor as per the manual. Check all engine grounds.
But use the FSM diagnostic flow charts to diagnose the problem. Good luck.
At 110K miles there may be maintenance issues. First have you ever changed the oxygen sensors. The sensors are supposed to be changed at 100k. The pre-cat sensors can cause running problems.
Have you pulled the sparkplugs to check their condition. At 100k, they are due to be changed. Is the Fuel pressure regulator original. If so pull the vacuum line and check for fuel and fuel smell. Even if it is okay you should think about changing it. Are the spark plug wires original? Pull into a dark area and raise the hood to look for arcing from the wires. They may not be the problem but can contribute. Check all of the vacuum lines - they rot over time and can cause problems. Check and see if the EGR is sticking open. Check the vent lines for the opti cap - it may be a good idea to check the opti cap and rotor as per the manual. Check all engine grounds.
But use the FSM diagnostic flow charts to diagnose the problem. Good luck.
Last edited by Silver96ce; Feb 28, 2014 at 02:40 PM.
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Instructor
Joined: Jun 2009
Posts: 109
Likes: 6
From: Scottsdale AZ
My 96 C-4 has been giving me some issues regarding stall out. My issue is last week I drove to work about 45 minutes, went to lunch and when it was time to return the engine would not start, or it trys to start and then die. I took it to the shop and consulted this forum, after which I had the ICM replaced since it was a problem that is somewhat common with this model. Today, I was experiencing this issue: The engine ran undriven for about 1 hr, I drove it to lunch and when I started it up it began doing the same thing; which is the idle which is 1000 rpm begins to dip and it gives teh impression of a stall beginning. The car runs after it starts moving but I am concern about this issue and seelk some advice as to what may be causing this issue. There are no indicator lights and there is no code for this problem.
Regard
xprtmdic
Regard
xprtmdic
sledge_78
.
Last edited by sledge_78; Feb 28, 2014 at 06:34 PM.
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
I have to agree with Sledge.
There is a multitude of things that can cause this kind of issue.
I noticed that you have just recently joined the forum. Which leads me to wonder if you also just recently purchased the car.
If this is the case, I might suggest doing the basic maintainence things first. Plugs, wires, PCV valve, air filter, check for vacuum leaks, etc. After you've done the basic tune up stuff, it may be clearer what the issue is, if it the tune up doesn't take care of it. It's amazing how an old worn out spark plug or wire can mess with a car.
There is a multitude of things that can cause this kind of issue.
I noticed that you have just recently joined the forum. Which leads me to wonder if you also just recently purchased the car.
If this is the case, I might suggest doing the basic maintainence things first. Plugs, wires, PCV valve, air filter, check for vacuum leaks, etc. After you've done the basic tune up stuff, it may be clearer what the issue is, if it the tune up doesn't take care of it. It's amazing how an old worn out spark plug or wire can mess with a car.
Thread Starter
6th Gear
Joined: Feb 2014
Posts: 6
Likes: 0
It appears you have gotten some good advice so far. It also seems you are chasing the infamous rabbit by replacing things that have not fixed the problem. As you know, modern day cars have many sensors, any one of which could fail and send inproper signals or voltages up the chain of engine operations. Since you have already spent money trying to fix this problem by replacing parts without success, it may be time to have a trained technician with the proper OBDII scan tools and diagnostic equipment to identify the culprit causing the problem. The actual result may be something quite simple or not but at least you will know what is causing the problem. I don't always like this alternative, but I would concede at some point and do it, than to keep spending and replacing. Besides, the boss will get impatient if it continues to happen on your lunch hour.
sledge_78
.
sledge_78
.
Thread Starter
6th Gear
Joined: Feb 2014
Posts: 6
Likes: 0
I have to agree with Sledge.
There is a multitude of things that can cause this kind of issue.
I noticed that you have just recently joined the forum. Which leads me to wonder if you also just recently purchased the car.
If this is the case, I might suggest doing the basic maintainence things first. Plugs, wires, PCV valve, air filter, check for vacuum leaks, etc. After you've done the basic tune up stuff, it may be clearer what the issue is, if it the tune up doesn't take care of it. It's amazing how an old worn out spark plug or wire can mess with a car.
There is a multitude of things that can cause this kind of issue.
I noticed that you have just recently joined the forum. Which leads me to wonder if you also just recently purchased the car.
If this is the case, I might suggest doing the basic maintainence things first. Plugs, wires, PCV valve, air filter, check for vacuum leaks, etc. After you've done the basic tune up stuff, it may be clearer what the issue is, if it the tune up doesn't take care of it. It's amazing how an old worn out spark plug or wire can mess with a car.
I understand! Just thought I would get a few insights from corvette enthusiast.
I had the car for several years, while I was in between deployments, this is the first that I experience this problem.
All the recommendations was well received.
Thanks
xprtmdic
Thread Starter
6th Gear
Joined: Feb 2014
Posts: 6
Likes: 0
First do you have a Factory Service manual - it is invaluable for repair and diagnosis. It has an entire section devoted to diagnostic procedures. If you already have it - go to section 6 of the engine portion of the manual for the diagnostic flow charts. Until then the following info from the manual should get you started.
At 110K miles there may be maintenance issues. First have you ever changed the oxygen sensors. The sensors are supposed to be changed at 100k. The pre-cat sensors can cause running problems.
Have you pulled the sparkplugs to check their condition. At 100k, they are due to be changed. Is the Fuel pressure regulator original. If so pull the vacuum line and check for fuel and fuel smell. Even if it is okay you should think about changing it. Are the spark plug wires original? Pull into a dark area and raise the hood to look for arcing from the wires. They may not be the problem but can contribute. Check all of the vacuum lines - they rot over time and can cause problems. Check and see if the EGR is sticking open. Check the vent lines for the opti cap - it may be a good idea to check the opti cap and rotor as per the manual. Check all engine grounds.
But use the FSM diagnostic flow charts to diagnose the problem. Good luck.
At 110K miles there may be maintenance issues. First have you ever changed the oxygen sensors. The sensors are supposed to be changed at 100k. The pre-cat sensors can cause running problems.
Have you pulled the sparkplugs to check their condition. At 100k, they are due to be changed. Is the Fuel pressure regulator original. If so pull the vacuum line and check for fuel and fuel smell. Even if it is okay you should think about changing it. Are the spark plug wires original? Pull into a dark area and raise the hood to look for arcing from the wires. They may not be the problem but can contribute. Check all of the vacuum lines - they rot over time and can cause problems. Check and see if the EGR is sticking open. Check the vent lines for the opti cap - it may be a good idea to check the opti cap and rotor as per the manual. Check all engine grounds.
But use the FSM diagnostic flow charts to diagnose the problem. Good luck.