A miss or stumble
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 9,600
Likes: 88
From: Springfield PA
Philly 'Burbs Events Coordinator
I did get a brief moment to look around Christmas eve. Last plug on the left may have a problem, I noticed just past the wire boot the porcelin was blackened, so maybe there's the problem. Went back up north on Tuesday and just got home but headed back up tomorrow through the New Year! Going to dig into it very early next year. If you'd be up to connect some evening next week let me know.
I think a lot of things can be ruled out (at least at first) since it is intermitent and only on the left, probably going to replace the plugs and wires.
The O2 is telling the ECM rich, can a computer tell even more?
Will check what you've suggested.
Was told a non burning cylinder could also give a lean code as the oxygen is unbruned as well.
And yes, I cleared the codes before rechecking.
Thanks for the help and input.
Do that yes. This way you will be able to see what the left O2 is telling the ECM.
Check the leads on the left bank and make sure they are good and firmly connected into the distributor, also check each of the left plugs and see what you see. There is a possibility one or more of the left plugs may not be firing during this time in which case the fuel wont burn, and the O2 will think its rich.
When you rechecked the codes, had you cleared them from the previous check?
Check the leads on the left bank and make sure they are good and firmly connected into the distributor, also check each of the left plugs and see what you see. There is a possibility one or more of the left plugs may not be firing during this time in which case the fuel wont burn, and the O2 will think its rich.
When you rechecked the codes, had you cleared them from the previous check?
Will check what you've suggested.
Was told a non burning cylinder could also give a lean code as the oxygen is unbruned as well.
And yes, I cleared the codes before rechecking.
Thanks for the help and input.
Last edited by Rex Ruby; Dec 27, 2006 at 09:01 PM.
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
It will tell you everything. If there is a problem with one or more cylinders not firing and dropping the fuel out the exhaust, youre likely to see the left O2 drop below temp and be too cool to function, which the laptop with Data Master can tell you. You cant tell this just by looking at the codes.
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 9,600
Likes: 88
From: Springfield PA
Philly 'Burbs Events Coordinator
Got back into it a few days ago and replaced the plugs and wires.
Runs a little better, no miss and no codes.
BUT it is still doing one of the issues I first described:
at low speed and steady gas pedal it will all of a sudden seem like a small boost in power and smoothness with the gas pedal in the same position.
At WOT she runs how she should.
Although replacing the O2 sensors, plugs and wires fixed the codes, there is still something malfunctioning.
I'm thinking I need to look at the EGR, OPTI and injectors?
Any tips on testing the EGR and injectors?
Any other suggestions?
Runs a little better, no miss and no codes.
BUT it is still doing one of the issues I first described:
at low speed and steady gas pedal it will all of a sudden seem like a small boost in power and smoothness with the gas pedal in the same position.
At WOT she runs how she should.
Although replacing the O2 sensors, plugs and wires fixed the codes, there is still something malfunctioning.
I'm thinking I need to look at the EGR, OPTI and injectors?
Any tips on testing the EGR and injectors?
Any other suggestions?
Heel & Toe
Joined: Sep 2006
Posts: 17
Likes: 1
I have the exact same symptoms.
I have also checked egr....looked for any vacuum leaks..replaced pcv...about to do plugs tommorrow.
The weird thing is it seems to be intermittent. At first I thought it was happening on closed loop....but it seems now whenever it feels like it.
Some days it runs perfect....others crap all day
Mine was throwing a code 65 right o2 sensor rich...replaced it...exactly the same prob.
Haven't checked tps iac and map yet....was gonna replace the plug wires....but think I will hold off and see if you guys come up with a solution here.
Thxs....will be watching for any new posts.
I have also checked egr....looked for any vacuum leaks..replaced pcv...about to do plugs tommorrow.
The weird thing is it seems to be intermittent. At first I thought it was happening on closed loop....but it seems now whenever it feels like it.
Some days it runs perfect....others crap all day
Mine was throwing a code 65 right o2 sensor rich...replaced it...exactly the same prob.
Haven't checked tps iac and map yet....was gonna replace the plug wires....but think I will hold off and see if you guys come up with a solution here.
Thxs....will be watching for any new posts.
Got back into it a few days ago and replaced the plugs and wires.
Runs a little better, no miss and no codes.
BUT it is still doing one of the issues I first described:
at low speed and steady gas pedal it will all of a sudden seem like a small boost in power and smoothness with the gas pedal in the same position.
At WOT she runs how she should.
Although replacing the O2 sensors, plugs and wires fixed the codes, there is still something malfunctioning.
I'm thinking I need to look at the EGR, OPTI and injectors?
Any tips on testing the EGR and injectors?
Any other suggestions?
Runs a little better, no miss and no codes.
BUT it is still doing one of the issues I first described:
at low speed and steady gas pedal it will all of a sudden seem like a small boost in power and smoothness with the gas pedal in the same position.
At WOT she runs how she should.
Although replacing the O2 sensors, plugs and wires fixed the codes, there is still something malfunctioning.
I'm thinking I need to look at the EGR, OPTI and injectors?
Any tips on testing the EGR and injectors?
Any other suggestions?
Heel & Toe
Joined: Sep 2006
Posts: 17
Likes: 1
Found it!
You guru's will probably get a good laugh 
After fiddling around with everything else for a few weeks...found it was the LEFT oxygen sensor...dah.
Teach me to be so cheap and only replace the right one.
Moral of the story...replace both
After fiddling around with everything else for a few weeks...found it was the LEFT oxygen sensor...dah.
Teach me to be so cheap and only replace the right one.
Moral of the story...replace both
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 9,600
Likes: 88
From: Springfield PA
Philly 'Burbs Events Coordinator
