Disconerting stumble still present...
Thread Starter
Melting Slicks
Joined: Sep 2000
Posts: 2,710
Likes: 1
From: Green Bay WI
Disconerting stumble still present...
Well, I changed the fuel filter, air filter, plugs and plug wires and my engine stumble is still there. :( Last night I went WOT against a Suzuki GSXR 750 from a stop light and after a second, the engine cut out or bogged down (whichever you prefer). It caught right after the cutout and went right back to WOT. The only thing I haven't done is the fuel pump - do you think this could be the culprit? Also, does anyone know if any sensors could be causing this? TIA!
[Modified by cprgmr, 10:07 PM 6/12/2002]
[Modified by cprgmr, 10:07 PM 6/12/2002]
Le Mans Master
Joined: Feb 2002
Posts: 7,858
Likes: 2
Re: Disconerting stumble still present... (cprgmr)
Considering that you had the ASR switched off, seems like the Throttle Position Sensor or the Mass Air Flow Sensor might be suspects (?)
Someone with more knowledge than I should chime in.
1st sentence says you did the fuel filter. If not, I would change jsut for good measure, especially if it has not been changed for 25,000 miles or more.
Someone with more knowledge than I should chime in.
1st sentence says you did the fuel filter. If not, I would change jsut for good measure, especially if it has not been changed for 25,000 miles or more.
Thread Starter
Melting Slicks
Joined: Sep 2000
Posts: 2,710
Likes: 1
From: Green Bay WI
Re: Disconerting stumble still present... (Lone Ranger)
Considering that you had the ASR switched off, seems like the Throttle Position Sensor or the Mass Air Flow Sensor might be suspects (?)
Someone with more knowledge than I should chime in.
1st sentence says you did the fuel filter. If not, I would change jsut for good measure, especially if it has not been changed for 25,000 miles or more.
Someone with more knowledge than I should chime in.
1st sentence says you did the fuel filter. If not, I would change jsut for good measure, especially if it has not been changed for 25,000 miles or more.
Thread Starter
Melting Slicks
Joined: Sep 2000
Posts: 2,710
Likes: 1
From: Green Bay WI
Re: Disconerting stumble still present... (Red 86 4+3)
Is this bog happening when you first give it the gas, or is it when it shifts gears?
[Modified by cprgmr, 6:52 AM 6/13/2002]
Racer
Joined: May 2001
Posts: 320
Likes: 0
From: TX
Re: Disconerting stumble still present... (cprgmr)
Does this sound like your problem? Floor it, the engine revs, hits about 4000 rpm, drops to 3600 and then goes to redline? This is what is happeneing to me.
My Opti went about 2 months ago and when it was replaced (under warranty) I was told my spark plug wires were bad. Since the ignition was bad, it fouled all my spark plugs. I think it also fouled my O2 sensors. I am getting a SES light occasionally. I have had the code scanned and one O2 sensor is definitely not reading correctly. It took me a while to change wires, so I am pulling the plugs again tonight to see if they are fouled again. If the plugs are not fouled, it is probably the bad O2 sensors causing the "stumble". I would recommend having your codes scanned, just to see if something is there. Also check your O2 sensors.
My Opti went about 2 months ago and when it was replaced (under warranty) I was told my spark plug wires were bad. Since the ignition was bad, it fouled all my spark plugs. I think it also fouled my O2 sensors. I am getting a SES light occasionally. I have had the code scanned and one O2 sensor is definitely not reading correctly. It took me a while to change wires, so I am pulling the plugs again tonight to see if they are fouled again. If the plugs are not fouled, it is probably the bad O2 sensors causing the "stumble". I would recommend having your codes scanned, just to see if something is there. Also check your O2 sensors.
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Instructor
Joined: Jan 2002
Posts: 172
Likes: 0
From: Garland TX
Re: Disconerting stumble still present... (cprgmr)
Just something simple ?? Pull your throttlebody and clean the back side of the butterfly also I cleaned the "valve body looking plate from the bottom" after a cleaning it seemed to run alot smoother('93 m6)also have you done the vac>/vent kit on your opti ? When I installed mine I noticed it had a bit aof a stumble at idle>
maybe not but maybe!
maybe not but maybe!
Thread Starter
Melting Slicks
Joined: Sep 2000
Posts: 2,710
Likes: 1
From: Green Bay WI
Re: Disconerting stumble still present... (kkonen)
Does this sound like your problem? Floor it, the engine revs, hits about 4000 rpm, drops to 3600 and then goes to redline? This is what is happeneing to me.
My Opti went about 2 months ago and when it was replaced (under warranty) I was told my spark plug wires were bad. Since the ignition was bad, it fouled all my spark plugs. I think it also fouled my O2 sensors. I am getting a SES light occasionally. I have had the code scanned and one O2 sensor is definitely not reading correctly. It took me a while to change wires, so I am pulling the plugs again tonight to see if they are fouled again. If the plugs are not fouled, it is probably the bad O2 sensors causing the "stumble". I would recommend having your codes scanned, just to see if something is there. Also check your O2 sensors.
My Opti went about 2 months ago and when it was replaced (under warranty) I was told my spark plug wires were bad. Since the ignition was bad, it fouled all my spark plugs. I think it also fouled my O2 sensors. I am getting a SES light occasionally. I have had the code scanned and one O2 sensor is definitely not reading correctly. It took me a while to change wires, so I am pulling the plugs again tonight to see if they are fouled again. If the plugs are not fouled, it is probably the bad O2 sensors causing the "stumble". I would recommend having your codes scanned, just to see if something is there. Also check your O2 sensors.
Thread Starter
Melting Slicks
Joined: Sep 2000
Posts: 2,710
Likes: 1
From: Green Bay WI
Re: Disconerting stumble still present... (flubuyu2)
Just something simple ?? Pull your throttlebody and clean the back side of the butterfly also I cleaned the "valve body looking plate from the bottom" after a cleaning it seemed to run alot smoother('93 m6)also have you done the vac>/vent kit on your opti ? When I installed mine I noticed it had a bit aof a stumble at idle>
maybe not but maybe!
maybe not but maybe!
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
Re: Disconerting stumble still present... (cprgmr)
Is this bog happening when you first give it the gas, or is it when it shifts gears?
It never happens when I first take off at slow speed or at WOT - it's always a short delay and then it happens. I hadn't really thought about that, but it may be happening on the 1-2 shift (although only occasionally). I think this is the third or fourth time it's ever done it. Think it might be something with the TV cable?
[Modified by cprgmr, 6:52 AM 6/13/2002]
It never happens when I first take off at slow speed or at WOT - it's always a short delay and then it happens. I hadn't really thought about that, but it may be happening on the 1-2 shift (although only occasionally). I think this is the third or fourth time it's ever done it. Think it might be something with the TV cable?
[Modified by cprgmr, 6:52 AM 6/13/2002]
Melting Slicks
Joined: Sep 2000
Posts: 3,150
Likes: 1
From: Carlsbad, CA CA
Re: Disconerting stumble still present... (Red 86 4+3)
I am almost positive that it is your Opti.
This problem is common for the early LT-1s. I would check that before you spend anymore money trouble shooting the fuel system.
Paul
This problem is common for the early LT-1s. I would check that before you spend anymore money trouble shooting the fuel system.
Paul
Heel & Toe
Joined: May 2002
Posts: 17
Likes: 0
From: Mantua NJ
Re: Disconerting stumble still present... (cprgmr)
Your problem sounds loke lack of fuel to me. You can get a fuel pressure guage and monitor the fuel pressue during acceleration. I had a similar problem and changed the fuel filter. It helped a little but changing the "sock" filter on the fuel pump did the trick. $22 at Pep Boys.
Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
Re: Disconerting stumble still present... (MEBVette)
Pull your codes first to see if the ECM is trying to tell you something. You can alsways use the SWAG method (scientific wild a-- guess) if there are no codes. :lol:
[Modified by ittlfly, 4:52 PM 6/16/2002]
[Modified by ittlfly, 4:52 PM 6/16/2002]
Thread Starter
Melting Slicks
Joined: Sep 2000
Posts: 2,710
Likes: 1
From: Green Bay WI
Re: Disconerting stumble still present... (cprgmr)
Thanks for the replies guys - looks like I'll take a look at the codes (if any), fuel pressure and opti. I can't imagine that the opti went bad, it doesn't seem to have any problems 99% of the time I drive... :confused:
