Colder plugs? 89A4
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From: altered state
St. Jude Donor '05
Colder plugs? 89A4
In an effort to help thwart detonation rather than get another set of rapidfire #5, picked up some Autolite #3926, supposedly a colder plug.
As a lot of you know I had a severe lean condition which seems to have been solved (find out on the dyno this week, but feels much better).....Sure the #5's are toast from all the detonation..I'll post pics after I take them out this afternoon, maybe there will be some carnage to look at
As a lot of you know I had a severe lean condition which seems to have been solved (find out on the dyno this week, but feels much better).....Sure the #5's are toast from all the detonation..I'll post pics after I take them out this afternoon, maybe there will be some carnage to look at
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St. Jude Donor '05
Guess what? These ARE NOT the plugs I originally installed! I put in Rapidfire # 5's when I bought it gapped at .040....
Had a compression test and some other work done last year (about 1000 miles) ago, looks like they replaced the plugs gapped at .055!!! WTF!!
Another reason to do it yourself...
As far as the coloring, doesn't look good. Opinions?
(new plugs getting gapped at .035 as per factory spec.)
Last edited by cv67; Dec 26, 2005 at 08:10 PM.
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St. Jude Donor '05
I did add some "sensor safe" octane boost to it last month after getting a tank of bad gas, only time I've used the stuff since Ive owned it. As far as the lean condition, it had a bad bog at 3200+ and pinged like a room full of windchimes... Heres a dyno sheet with the A/F ratio printout taken a few weeks ago....
Oil looks clean, same with coolant. Had block and radiator flushed a few weeks back, still looks clean.
Sun CR, I replaced the MAF, burnoff and power relays 2 days ago, car feels better.
Oil looks clean, same with coolant. Had block and radiator flushed a few weeks back, still looks clean.
Sun CR, I replaced the MAF, burnoff and power relays 2 days ago, car feels better.
Le Mans Master
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From: San Diego, Ca
Mine look like that when I've used Octane Boost so I'm going to say it's normal.
Your Charts don't make a whole lot of sense to me, but if the A/F is 18/1, Yikes!. Scan that puppy and see what the Integrator/BLM's are doing - look at a couple of cells too - not just at idle. A faulty MAF can cause it to run lean and now that you've replaced it, I'd want to see what the O2 is sensing and how it's adding or subtracting fuel.
Your Charts don't make a whole lot of sense to me, but if the A/F is 18/1, Yikes!. Scan that puppy and see what the Integrator/BLM's are doing - look at a couple of cells too - not just at idle. A faulty MAF can cause it to run lean and now that you've replaced it, I'd want to see what the O2 is sensing and how it's adding or subtracting fuel.
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St. Jude Donor '05
Would a dyno shop have the ability to do that? They were closed today. If they are open tomorrow and its not raining I'd like to take it back and at least have the A/F ratio checked again. Should I replace the 02 again? Newer Bosch in there now, no codes. Unfortunately I have no software nor the knowledge to work with it to find this stuff out....Looks like I may have to eventually though if I plan on keeping FI vettes.
What do you recommend?
What do you recommend?
Last edited by cv67; Dec 26, 2005 at 11:31 PM.
Le Mans Master
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From: San Diego, Ca
If they have a Scanner - yes. What's at the tailpipe though, isn't always what the Computer is seeing. The key is to find out why the ECM thinks it's perfect (14.8/1) - when it's not. Few, if any fuel problems (absent a specific code) are the fault of the O2 (though I'd hesitate to say that the Octane Boost didn't muck it up) If it's reporting a rich condition, then the ECM decreases injector pulse width to compensate for it and you get a lean exhaust. You need to find out why the 02 think it's rich or lean - the MAF is good starting point, but a scan will show if it's happy now and a tailpipe sniff will confirm all is well. If not, then use the 44 and/or 45 Charts (diagnostic aids) to find the culprit.
Le Mans Master
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How is the car running with the new plugs? If it seems to be running good if I were you I'd check it on the dyno already, you may have installed all the parts you need to correct your problem.
Did you replace that sensor today?
Did you replace that sensor today?
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From: altered state
St. Jude Donor '05
Hippy-They didn't carry it, said ordering its a lost cause. 
(The one between #6 and 8 cyl). I only got the drivers side done as far as plugs go, gotta do the rest in the morning. THis thing better be right, getting tired of messin with it.
(The one between #6 and 8 cyl). I only got the drivers side done as far as plugs go, gotta do the rest in the morning. THis thing better be right, getting tired of messin with it.
Melting Slicks
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From: Lufkin Texas
St. Jude Donor '05-'06
They don't really look that bad to me, except for being over gapped. According to a chart I have, I'd say yours look closer to normal than any of the others. They do look a little lean glazed but not bad.
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St. Jude Donor '05
'k, new plugs gapped at .035 and car runs worse, know at some point some wires have gotten a little close to the smog rails,perhaps in the course of removing them they got worse...Some were a little stiff like thye got heat damaged.. in OD has a sight surge (miss)...Putting wires on (again) tomorrow. If this thing isnt right I'm ramming it into a flippin' wall!
$
$ $
$
$ $
Le Mans Master
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Originally Posted by cuisinartvette
'k, new plugs gapped at .035 and car runs worse, know at some point some wires have gotten a little close to the smog rails,perhaps in the course of removing them they got worse...Some were a little stiff like thye got heat damaged.. in OD has a sight surge (miss)...Putting wires on (again) tomorrow. If this thing isnt right I'm ramming it into a flippin' wall!
$ $ $
$
$ $I've had problems with plug wiresw 1 & 3 crossing over each other down by the plugs and make sure you didn't put 5 on 7 an vice versa.
Le Mans Master
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Originally Posted by cuisinartvette
I'm going to wire it open full throttle and turn a hose on it.
Make sure you aim the hose directly at the Opti spark. I hear they like moisture.
P.S. If you don't have an Opti on your 89 I think you should mod it and put one on.
Put a 92 or 93 on, they work the best.
Le Mans Master
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From: The Motor City
Originally Posted by hippy
Make sure you aim the hose directly at the Opti spark. I hear they like moisture.
P.S. If you don't have an Opti on your 89 I think you should mod it and put one on. Put a 92 or 93 on, they work the best.
P.S. If you don't have an Opti on your 89 I think you should mod it and put one on.
Put a 92 or 93 on, they work the best.
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From: altered state
St. Jude Donor '05
Originally Posted by hippy
Make sure you aim the hose directly at the Opti spark. I hear they like moisture.
P.S. If you don't have an Opti on your 89 I think you should mod it and put one on. Put a 92 or 93 on, they work the best.
P.S. If you don't have an Opti on your 89 I think you should mod it and put one on.
Put a 92 or 93 on, they work the best.
