[pic] tell me what's wrong here
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,483
Likes: 4
From: middle TN
[pic] tell me what's wrong here
Yes I know I got spark problems with the retard. But I am a retard, seeing as how this is my first datalog. Graph shows about 10 seconds of a more or less steady cruise around 48 mph, then get on the gas and I get all kindsa knock and stuff. Is this indicative of an opti problem? Is there enough data shown to be able to tell anything?
(sorry for the bad colors...it's a screen capture that had to fit on a 3.5 floppy from the laptop)
(sorry for the bad colors...it's a screen capture that had to fit on a 3.5 floppy from the laptop)
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Is this sort of thing happening hot and cold? If you let it sit and idle for about 25-30 seconds then try to rev it up quickly, does it hesitate? If its only doing it after its up to working temperature id be looking towards O2 sensors. Can you do another log with the oxygen sensors on the graph?
Drifting
Joined: Apr 1999
Posts: 1,261
Likes: 6
From: Middletown New Jersey
Do you have any mods like RR's, headers etc.. Your knock count total is unbelievably high. I'm not very knowledgeable about Opti's but I wouldn't think that it is the issue.
What octane gas do you run?
What octane gas do you run?
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,483
Likes: 4
From: middle TN
Rick, what exactly do you mean about the O2 "pulling timing"? I was under the impression it's normal for O2 values to fluctuate wildly, within limits. BTW, no mods, run 93 octane, also idles pretty rough when cold or hot, open and closed loop. Idles 750 rpm hot...I'm thinking that's a bit high??
As luck would have it, I gotta leave for a couple days just as I was getting into this datalogging stuff!
Will pick up when I get back. Thanks for the replies.
As luck would have it, I gotta leave for a couple days just as I was getting into this datalogging stuff!
Will pick up when I get back. Thanks for the replies.
Racer
Joined: Jan 2002
Posts: 322
Likes: 0
From: ruston la
Originally Posted by Scooter 94
about 10 seconds of a more or less steady cruise around 48 mph, then get on the gas and I get all kindsa knock and stuff.
You say you get on the gas after cruising at 48 and it causes the knock. Other than the beginning and end, I see no change in throttle. Is it supposed to be there or did you word it wrong?
Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,483
Likes: 4
From: middle TN
Almost coasting would be a better way to say it. Very little throttle, then step on it some, and get the missing/knock. Seems to be getting worse, in other words, less and less throttle is required before it gets rough.
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Originally Posted by Scooter 94
Almost coasting would be a better way to say it. Very little throttle, then step on it some, and get the missing/knock. Seems to be getting worse, in other words, less and less throttle is required before it gets rough.
What have you cleaned?
What have you replaced?
What do your plugs look like?
Is your MAF nice and clean?
Is your IAT sensor clean and where it should be?
How old are the leads and are they all connected firmly?
Are all the connections to sensors clean and firmly connected?
Are the injectors clean and not leaking?
How old is the fuel filter?
How many miles on the car?
Is the car hard to start?
Just from what you have said so far it would be hard for anyone to call it distributor related, its sounds more engine management sensor related at this stage...
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Thread Starter
Drifting
Joined: Sep 2003
Posts: 1,483
Likes: 4
From: middle TN
The more I've had a change to study this stuff the more I see that it's impossible to make a good diagnosis based on one single data record (among 5 to 10 every second). I'm seeing some trends that may be important, but it's a huge learning curve for me.
Once I get a better handle on it (and time to tackle the problem in ernest) I'll start a new thread w/more info. Thanks for the replies.
Once I get a better handle on it (and time to tackle the problem in ernest) I'll start a new thread w/more info. Thanks for the replies.