Still have a problem! Opinions needed.
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 936
Likes: 3
From: Prattville, AL. My Dog Thinks I'm Cool!
Still have a problem! Opinions needed.
Hi all! I have a problem with my '92 that I can't figure out. When I accelerate slowly my engine feels/sounds like it is missing. As I continue to accelerate (without changing my throttle position) the engine will suddenly come to life and run fine, like turning on a switch. This only happens when the car is in closed loop. I have replaced the fuel filter, injectors (checked the fuel pressure it's ok), plugs, plug wires, opti-spark, waterpump, coolant temp sensor, intake air temp sensor, manifold absolute pressure sensor, throttle position sensor, O2 sensors. I've used two different scanner tools and EVERYTHING reads within factory spec. There are NO error codes. At wide open throttle this thing runs like a scalded dog. Any ideas?
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Have you checked for vacuum leaks?
Have you cleaned out the throttle body and the IAC path?
Check EGR function to make sure its not leaking or allowing exhaust gas to pass when it shouldnt.
Check the CCP is functioning correctly.
Have you cleaned out the throttle body and the IAC path?
Check EGR function to make sure its not leaking or allowing exhaust gas to pass when it shouldnt.
Check the CCP is functioning correctly.
Melting Slicks
Joined: Jun 2004
Posts: 3,032
Likes: 4
also stuff that wouldn't show upin the tests you did.
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 936
Likes: 3
From: Prattville, AL. My Dog Thinks I'm Cool!
1. Yes, no leaks 2.EGR has been removed and chip calabrated for it. 3. CCM is working fine
Last edited by pletner; Jan 3, 2007 at 12:08 PM. Reason: CCM instead of CCP
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Charcol canisiter purge. Connected to the right hand side of the throttle body under the PCV connection.
Did you remove the A.I.R. system as well?
Checked for exhaust leaks before the O2s?
Did you remove the A.I.R. system as well?
Checked for exhaust leaks before the O2s?
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 936
Likes: 3
From: Prattville, AL. My Dog Thinks I'm Cool!
I removed the A.I.R. system, I've checked for leaks before the O2's and I can't find any. What should I look for on the CCP?
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Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
The charcol canister is in the back of the car, on the right hand side. It connects to a solenoid which is located towards the front/right of the intake manifold, from there it connects to the throttle body on the right hand side. Pull that hose off at the throttle body and block both the hose and the fitting on the throttle body. If this makes some sort of radical improvement then look at diagnosing the system.
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 936
Likes: 3
From: Prattville, AL. My Dog Thinks I'm Cool!
He states that in his opening post mate.
Do you have a service manual??
The charcol canister is in the back of the car, on the right hand side. It connects to a solenoid which is located towards the front/right of the intake manifold, from there it connects to the throttle body on the right hand side. Pull that hose off at the throttle body and block both the hose and the fitting on the throttle body. If this makes some sort of radical improvement then look at diagnosing the system.
Do you have a service manual??
The charcol canister is in the back of the car, on the right hand side. It connects to a solenoid which is located towards the front/right of the intake manifold, from there it connects to the throttle body on the right hand side. Pull that hose off at the throttle body and block both the hose and the fitting on the throttle body. If this makes some sort of radical improvement then look at diagnosing the system.
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
If that leads nowhere id try the stock chip if you still have it.
The fact that everything reads within factory spec on a scan tool doesnt mean much at all really, its no indication that every system is functioning as it should. There is a fair few things that can work incorrectly and the sensors can still give readings within spec.
The fact that everything reads within factory spec on a scan tool doesnt mean much at all really, its no indication that every system is functioning as it should. There is a fair few things that can work incorrectly and the sensors can still give readings within spec.
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 936
Likes: 3
From: Prattville, AL. My Dog Thinks I'm Cool!
If that leads nowhere id try the stock chip if you still have it.
The fact that everything reads within factory spec on a scan tool doesnt mean much at all really, its no indication that every system is functioning as it should. There is a fair few things that can work incorrectly and the sensors can still give readings within spec.
The fact that everything reads within factory spec on a scan tool doesnt mean much at all really, its no indication that every system is functioning as it should. There is a fair few things that can work incorrectly and the sensors can still give readings within spec.
Racer
Joined: Oct 2006
Posts: 286
Likes: 0
From: Olympia Washington 91 Z07 Coupe, 6spd, Borla Exhaust, Perf. Ignition, K&N Filter
this will sound really stupid and im sorry if im just wasting your time
have you thought about the gas you are using, are you using 92 and is it a high quality gas, like shell, texaco or chevron? sometimes bad gas can really cause some temporary and permanent problems like bad acceleration and pinging, on hills and high altitudes
have you thought about the gas you are using, are you using 92 and is it a high quality gas, like shell, texaco or chevron? sometimes bad gas can really cause some temporary and permanent problems like bad acceleration and pinging, on hills and high altitudes
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 936
Likes: 3
From: Prattville, AL. My Dog Thinks I'm Cool!
this will sound really stupid and im sorry if im just wasting your time
have you thought about the gas you are using, are you using 92 and is it a high quality gas, like shell, texaco or chevron? sometimes bad gas can really cause some temporary and permanent problems like bad acceleration and pinging, on hills and high altitudes
have you thought about the gas you are using, are you using 92 and is it a high quality gas, like shell, texaco or chevron? sometimes bad gas can really cause some temporary and permanent problems like bad acceleration and pinging, on hills and high altitudes
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Im not sure if a 92 will run in closed loop with that unpluged though. If it stays in open loop, that explains why it makes a difference.
Mods are listed in his sig on first post.
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 936
Likes: 3
From: Prattville, AL. My Dog Thinks I'm Cool!
My IAT is in the stock location, I've checked the wiring and it's o.k. I think it's running in open mode with it unplugged, thats why it runs better.
Thread Starter
Burning Brakes
Joined: Jun 2003
Posts: 936
Likes: 3
From: Prattville, AL. My Dog Thinks I'm Cool!
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Start from the top and work through it all mate, check everything. If you can get a hold of a couple O2s that you know work, swap them out and see if that helps.
Check the coolant temp sensor.
Are you getting any smoke of any kind?
Check the coolant temp sensor.
Are you getting any smoke of any kind?