Car bogs, stumbles, misses, but only when hot.
07-26-2005, 10:08 PM
#122
Registered User
Join Date: Jul 2005
Posts: 5
Re: Car bogs, stumbles, misses, but only when hot.
same here my car is running crappy all the time now.... It started out just like Mrboss now it runs like crap all of the time.... I am going to change plug wires and plugs this time and pray for the best....
07-27-2005, 12:18 AM
#124
Registered User
Join Date: Nov 2004
Posts: 36
Re: Car bogs, stumbles, misses, but only when hot.
What's up man?, I replaced my opti-crap twice in two years. 
New opti-craps are very unpredictable. My 1994 Z28 did the exact same thing, after 20 minutes of running, it started backfiring and bucking. I purchased a delteg and my problem did not go away, 
but I had a bad optical sensor in my brand new opti-crap, so I put my old opti-crap back in and used the optical sensor with my new delteg and my problem is gone, three years running. 
If your optical sensor is bad you need to replace it, the delteg will not work with a bad sensor. But I highly recomend a delteg, you will not regret it, put it on and watch that baby revvvvvv. 
New opti-craps are very unpredictable. My 1994 Z28 did the exact same thing, after 20 minutes of running, it started backfiring and bucking. I purchased a delteg and my problem did not go away, but I had a bad optical sensor in my brand new opti-crap, so I put my old opti-crap back in and used the optical sensor with my new delteg and my problem is gone, three years running. If your optical sensor is bad you need to replace it, the delteg will not work with a bad sensor. But I highly recomend a delteg, you will not regret it, put it on and watch that baby revvvvvv.
07-27-2005, 02:28 AM
#125
Registered User
Join Date: Jul 2005
Location: NY
Posts: 74
Re: Car bogs, stumbles, misses, but only when hot.
I have the same problem, I just started this thread, http://web.camaross.com/forums/showthread.php?t=385511
Honestly this is an ideantical problem and we are not the first to have it, I think it is an issue people can't seem to solve. case in point here are archives from 2002 Identical problem with the LT1. http://web.camaross.com/forums/archi...-6172-p-1.html
Anyway here is my original post with info on what I have been doing with no positive results as of yet.
Hello this is my first post here so I will introduce my self before I burden you guys with my problem.
First off My name is Robert and I live in Farmingville, NY
I own a Black 94 Z28 (95K) with the Following mods
De-screened MAF
Tb by-pass
Fan Switch
Moroso CAI
Jet Air-Foil
Free Ram-Air
Flowmaster cat-back
Trans-Go shift kit
BMR Control Arms
BMR Torque arm
LT4 knock module
160 degree thermostat
Use only Mobile one synthetic
My car has been really great with plenty of HP but just recently it has been backfiring and has a real loss of power and horrible throttle response under 2500RPM. But only backfires when it warms up.
I have done a few things to try and fix this problem.
For example
Replaced All Plugs and wires (Used Di-electric grease)
Replaced Fuel Filter
Replaced Intake Air Temp Sensor
Replaced PCV
Replaced Air Filter (Oiled air filter as well)
Cleaned Throttle body with Carb Cleaner
Cleaned the Diodes in the MAF with Electronics cleaner
Used Octane booster
Used Fuel injector Cleaner
Checked Fuses and Battery
Disconnected battery for about 10 hours to reset the Computer
Disconnected the MAF and ran engine
Disconnected EGR Valve and ran engine
Well I'm still having the problem and every mechanic I talk to suggest replacing something different I don't want to have someone replace many expensive parts because they are not familiar with the LT1 engine. Some things I have been told to replace.
EGR Valve and Vacuum solenoid
O2 Sensor
Fuel Pressure Regulator
Map Sensor
MAF Sensor
Coolant Temp sensor
Ignition control module
Intake air control valve
If there is any way you can help it would be greatly appreciated.
Thank you,
Robert
Honestly this is an ideantical problem and we are not the first to have it, I think it is an issue people can't seem to solve. case in point here are archives from 2002 Identical problem with the LT1. http://web.camaross.com/forums/archi...-6172-p-1.html
Anyway here is my original post with info on what I have been doing with no positive results as of yet.
Hello this is my first post here so I will introduce my self before I burden you guys with my problem.
First off My name is Robert and I live in Farmingville, NY
I own a Black 94 Z28 (95K) with the Following mods
De-screened MAF
Tb by-pass
Fan Switch
Moroso CAI
Jet Air-Foil
Free Ram-Air
Flowmaster cat-back
Trans-Go shift kit
BMR Control Arms
BMR Torque arm
LT4 knock module
160 degree thermostat
Use only Mobile one synthetic
My car has been really great with plenty of HP but just recently it has been backfiring and has a real loss of power and horrible throttle response under 2500RPM. But only backfires when it warms up.
I have done a few things to try and fix this problem.
For example
Replaced All Plugs and wires (Used Di-electric grease)
Replaced Fuel Filter
Replaced Intake Air Temp Sensor
Replaced PCV
Replaced Air Filter (Oiled air filter as well)
Cleaned Throttle body with Carb Cleaner
Cleaned the Diodes in the MAF with Electronics cleaner
Used Octane booster
Used Fuel injector Cleaner
Checked Fuses and Battery
Disconnected battery for about 10 hours to reset the Computer
Disconnected the MAF and ran engine
Disconnected EGR Valve and ran engine
Well I'm still having the problem and every mechanic I talk to suggest replacing something different I don't want to have someone replace many expensive parts because they are not familiar with the LT1 engine. Some things I have been told to replace.
EGR Valve and Vacuum solenoid
O2 Sensor
Fuel Pressure Regulator
Map Sensor
MAF Sensor
Coolant Temp sensor
Ignition control module
Intake air control valve
If there is any way you can help it would be greatly appreciated.
Thank you,
Robert
Last edited by Netwrkengeer; 07-27-2005 at 02:30 AM.
07-27-2005, 06:53 AM
#126
Registered User
Thread Starter
Join Date: Jan 2003
Location: Cape Cod, MA
Posts: 257
Re: Car bogs, stumbles, misses, but only when hot.
Originally Posted by hammersz28
What's up man?, I replaced my opti-crap twice in two years. New opti-craps are very unpredictable. My 1994 Z28 did the exact same thing, after 20 minutes of running, it started backfiring and bucking. I purchased a delteg and my problem did not go away, but I had a bad optical sensor in my brand new opti-crap, so I put my old opti-crap back in and used the optical sensor with my new delteg and my problem is gone, three years running. If your optical sensor is bad you need to replace it, the delteg will not work with a bad sensor. But I highly recomend a delteg, you will not regret it, put it on and watch that baby revvvvvv.
New opti-craps are very unpredictable. My 1994 Z28 did the exact same thing, after 20 minutes of running, it started backfiring and bucking. I purchased a delteg and my problem did not go away, but I had a bad optical sensor in my brand new opti-crap, so I put my old opti-crap back in and used the optical sensor with my new delteg and my problem is gone, three years running. If your optical sensor is bad you need to replace it, the delteg will not work with a bad sensor. But I highly recomend a delteg, you will not regret it, put it on and watch that baby revvvvvv. 
07-27-2005, 08:11 AM
#128
Registered User
Join Date: Jan 2005
Location: tonawanda, ny
Posts: 128
Re: Car bogs, stumbles, misses, but only when hot.
Ok, this way help some of you with this problem, but not all of you (mrboss). My brothers Firehawk had the same symptoms. It would run and start awesome for about 10-15 minutes. then it would run like crap, suck gas like a pig, and not want to re-fire at all. It turned out to be the 11 dollar coolant temp sender on the front of the water pump. It was constantly telling the computer that the motor was cold. As soon as the motor was warmed up, the mixture would be WAY TOO RICH causing all of these problems. I would suggest a diagnostic check with a scanner with the motor warmed up. MrBoss, I see your coolant temps were normal, so I really can't help you out any.Sorry. For the others, I would replace this cheap part before spending big bucks on an opti, new cat, new plugs and wires, etc......
07-27-2005, 09:06 AM
#129
Registered User
Join Date: Jul 2005
Location: NY
Posts: 74
Re: Car bogs, stumbles, misses, but only when hot.
Originally Posted by MRBoss429x
Isnt the optical snesor part of the opti? So if you put in a new opti, you ut in an optical sensor as well? Im a bit confused now.
So the delteq eliminates these issues.
On the other thread hammerz said he didn't see any increased performance other then a smooth and fast rev. which doesn't directly relate to HP.
07-27-2005, 09:20 AM
#130
Registered User
Thread Starter
Join Date: Jan 2003
Location: Cape Cod, MA
Posts: 257
Re: Car bogs, stumbles, misses, but only when hot.
Originally Posted by Netwrkengeer
Yes, but the problem with installing new opti's are they have a tendency to break quickly sometimes during the install, but in the originals the optical sensor seems to be ok forever, minus some carbon. So the problem the original Opti's have seem to be directly related to cap & rotor wear other issues include high voltage passing directly through the opti which causes internal arc-over and cross-firing. Well also factor in the fact that the terminal traces molded into the distributor cap are extremely close to each other.
So the delteq eliminates these issues.
On the other thread hammerz said he didn't see any increased performance other then a smooth and fast rev. which doesn't directly relate to HP.
So the delteq eliminates these issues.
On the other thread hammerz said he didn't see any increased performance other then a smooth and fast rev. which doesn't directly relate to HP.
07-27-2005, 02:00 PM
#132
Registered User
Thread Starter
Join Date: Jan 2003
Location: Cape Cod, MA
Posts: 257
Re: Car bogs, stumbles, misses, but only when hot.
Finally dove in to take a look. Does this look like coolant leaking from WP onto opti or oil? :
http://memimage.cardomain.net/member...46_44_full.jpg
http://memimage.cardomain.net/member...46_45_full.jpg
http://memimage.cardomain.net/member...46_44_full.jpg
http://memimage.cardomain.net/member...46_45_full.jpg
07-27-2005, 02:29 PM
#133
Registered User
Join Date: Jul 2005
Location: NY
Posts: 74
Re: Car bogs, stumbles, misses, but only when hot.
Looks like oil/carbon
That is pretty normal for these cars. It is how ever an issue because the 93/94 models do not have sealed opti units.
Although I don't think it is an issue large enough for concern. Your opti maybe bad from age but I wouldn't think it is due to the deposits.
That is pretty normal for these cars. It is how ever an issue because the 93/94 models do not have sealed opti units.
Although I don't think it is an issue large enough for concern. Your opti maybe bad from age but I wouldn't think it is due to the deposits.
07-27-2005, 07:38 PM
#135
Registered User
Join Date: Nov 2004
Posts: 36
Re: Car bogs, stumbles, misses, but only when hot.
What's up?, I know this may get a little expensive, but if you are going to keep your z, then I ask you to consider getting a delteg to go along with your new opti-crap, because from my experiences, you will have trouble with that new opti-crap. 
For some reason the new ones are not as good as the originals. As for as hp the delteg gives you smoother revs @ higher RPMS, which does make a difference. 
If you are not planning on keeping your classic LT1, then don"t worry about it. More than likely the optical sensor in your opti-crap is either being blocked by oil and carbon build-up or rust because its non-vented, that was my problem. I took my old opti-crap apart and boy was it NASTY.
For some reason the new ones are not as good as the originals. As for as hp the delteg gives you smoother revs @ higher RPMS, which does make a difference. If you are not planning on keeping your classic LT1, then don"t worry about it. More than likely the optical sensor in your opti-crap is either being blocked by oil and carbon build-up or rust because its non-vented, that was my problem. I took my old opti-crap apart and boy was it NASTY.