New User: L98 Engine Trouble
Thread Starter
Racer
Joined: Feb 2004
Posts: 445
Likes: 1
From: Atlanta GA
New User: L98 Engine Trouble
Good Evening All. I am pleased to be a new member of the Forum. I have an '89 that is lightly modified with around 60,000 original miles. Because of the computer chip I run only premium fuel. Over the past few months, I've noticed that under hard acceleration, I hear a pinging from 2,800 - 4,500 rpm. I only notice the noise at that rpm range and its especially prevalent in first and second gear. Is there an obvious cause of this? Are there any simple fixes that I could look into, or does it sound like the ole L98 is trying to get a foot into "Motor Heaven". Thanks for any responses!!
[Modified by Midnight89, 3:35 AM 2/4/2004]
[Modified by Midnight89, 3:35 AM 2/4/2004]
Thread Starter
Racer
Joined: Feb 2004
Posts: 445
Likes: 1
From: Atlanta GA
Re: New User: L98 Engine Trouble (Midnight89)
I haven't changed the plugs in the past five years. The stock plugs were replaced with AC Delco plugs about 6 years ago (40,000 miles). I guess it sounds as if its time to change the plugs.
Do you have a recommendation as to a particular brand and gap? Should I also pick up a new set of wires?
(The motor only has the basic mods: K&N filter and airbox, TPI Airfoil, MAF Mod, Throttle Body Plenum Spacer.)
Do you have a recommendation as to a particular brand and gap? Should I also pick up a new set of wires?
(The motor only has the basic mods: K&N filter and airbox, TPI Airfoil, MAF Mod, Throttle Body Plenum Spacer.)
Le Mans Master
Joined: Aug 2003
Posts: 9,884
Likes: 3
From: Magnolia Mississippi
St. Jude '03-'04-'05-'06-'07
Re: New User: L98 Engine Trouble (Midnight89)
:yesnod: Yea, think its probably about time for a plug change: AC Delco Spitfires, think gap is 045... as for wires MSD or any good brand... stay 8mm and you can use your current looms, 8.5 and you'll need new one.. and why not a new cap too... :thumbs:
Thread Starter
Racer
Joined: Feb 2004
Posts: 445
Likes: 1
From: Atlanta GA
Re: (Z-07 freak)
Thanks for all of the help everyone! I have changed the fuel filter about 2 years ago, but with as much as the car sits in the garage, I'm sure a change couldn't hurt. As for the plugs, I'll go pick up a new set of Delco Splitfire plugs and wires and will gap to 35 (as I am still using the stock ignition).
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Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
Re: (scorp508)
I agree with the replies above...also check the cap and rotor for wear or carbon tracking/burn marks,build up etc.I had laess than 15K on mine and it went south.
One last thing,be sure the EGR isnt sticking.While it may not be the problem,never hurts to check it.
:cheers:
One last thing,be sure the EGR isnt sticking.While it may not be the problem,never hurts to check it.
:cheers:
Thread Starter
Racer
Joined: Feb 2004
Posts: 445
Likes: 1
From: Atlanta GA
Re: (Bill's86Coupe)
Scorp508: would you prefer the Rapidfire over the Splitfire? I'll get the plugs and wires (I'll stick with 8mm just to make this easier), and Mid-America has the Accel Hi-Performance Distributor Caps for $30 (which is $30 well spent).
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: (Midnight89)
I don't think either will really make a huge difference. :) If you're interested in seeing what others have done I'll run down the list of what I run for ignition. A mostly stock engine is perfectly fine with stock replacement parts. :yesnod:
1. Conrad Cap & Rotor w/brass terminals (Got this cheap at autozone)
2. Conrad Ignition Control Module (About $15 at autozone too)
3. MSD HEI In-Cap Ignition Coil
4. MSD Low Resistance HEI Bushing
5. MSD Super Conductor 8.5mm plug wires.
6. AC Delco Rapidfire #5
1. Conrad Cap & Rotor w/brass terminals (Got this cheap at autozone)
2. Conrad Ignition Control Module (About $15 at autozone too)
3. MSD HEI In-Cap Ignition Coil
4. MSD Low Resistance HEI Bushing
5. MSD Super Conductor 8.5mm plug wires.
6. AC Delco Rapidfire #5
Instructor
Joined: Sep 1999
Posts: 197
Likes: 0
From: Ridgefield CT
Re: New User: L98 Engine Trouble (Midnight89)
I have never read anything good about splitfire plugs, go with the AC Delco Rapidfires. Also, I think the correct gap for Rapidfires is .045", the manual says.035" but I think that's for the regular AC Delco plugs, Rapidfires are a step up from regular plugs.
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: New User: L98 Engine Trouble (skidmark)
Also, I think the correct gap for Rapidfires is .045
Instructor
Joined: Sep 1999
Posts: 197
Likes: 0
From: Ridgefield CT
Re: New User: L98 Engine Trouble (Midnight89)
The ones I bought were gapped at .045" right out of the box, checked each one and didn't have to change any of them. It's been a while but I seem to remember emailing AC Delco and they told me to stay with .045" for the L98.
Le Mans Master
Joined: Jan 2003
Posts: 5,858
Likes: 7
From: Santa Maria CA
Re: New User: L98 Engine Trouble (Midnight89)
My 86 did the same before. It turned out to be the #1 spark plug. It had a hairline crack in the white glass like insulation that the boot slides over. Replaced the plug and the problem went away. :D
Safety Car
Joined: Feb 2001
Posts: 4,397
Likes: 0
From: Looks like I picked the wrong week to stop sniffin glue Orlando
Re: New User: L98 Engine Trouble (Midnight89)
I had an ignition miss problem awhile back. I noticed the stock ignition system seemed kind of weak. I replaced the plugs, wires, ignition module and coil. I couldn’t believe just the visual difference in the spark produced let alone the better all around feel of the engine.
Parts used were Holley Ignition module, Hypertech coil, MSD Wires, and NGK V-Groove plugs.
I have a set of NGK V-Groove in my Nissan Truck. Think they have been in there for about 6 or 7 years, and they still look brand new. I check them annually and they always look perfect, so needless to say that’s what I run in the vette.
Jus my 2 cents.
:cheers:
Parts used were Holley Ignition module, Hypertech coil, MSD Wires, and NGK V-Groove plugs.
I have a set of NGK V-Groove in my Nissan Truck. Think they have been in there for about 6 or 7 years, and they still look brand new. I check them annually and they always look perfect, so needless to say that’s what I run in the vette.
Jus my 2 cents.
:cheers:
Thread Starter
Racer
Joined: Feb 2004
Posts: 445
Likes: 1
From: Atlanta GA
Re: New User: L98 Engine Trouble (IBEAM700)
Thanks for the insight. I think that I've decided exactly what my "tune-up" will include. My lack of technical product knowledge has prompted me to pull together suggestions from several different people and I've come up with this combo:
1. AC Delco Rapidfire #5 plugs gapped at .045"
2. Conrad Distributor Cap and Rotor with Brass terminals
3. Conrad Ignition Control Module
4. Hypertech Coil OR Accel HEI Super Coil
5. Accel or MSD plug wires--8mm to avoid having to change the wire looms
6. AC Delco Fuel Filter (never hurts to change)
The combo seems as if it would work for me. Should be able to get it all for around $200-$250. I'm hoping this combo will not only solve the problem, but it would serve as a good compliment to any later electrical or performance additions (MSD 6AL).
My only concern is the Hypertech Power Coil. Mid-America claims that the coil requires a higher quality distributor cap and rotor to withstand the higher voltages. Will the Conrad suffice, or should I look into an Accel Hi-Performance Cap, or some other brand?
1. AC Delco Rapidfire #5 plugs gapped at .045"
2. Conrad Distributor Cap and Rotor with Brass terminals
3. Conrad Ignition Control Module
4. Hypertech Coil OR Accel HEI Super Coil
5. Accel or MSD plug wires--8mm to avoid having to change the wire looms
6. AC Delco Fuel Filter (never hurts to change)
The combo seems as if it would work for me. Should be able to get it all for around $200-$250. I'm hoping this combo will not only solve the problem, but it would serve as a good compliment to any later electrical or performance additions (MSD 6AL).
My only concern is the Hypertech Power Coil. Mid-America claims that the coil requires a higher quality distributor cap and rotor to withstand the higher voltages. Will the Conrad suffice, or should I look into an Accel Hi-Performance Cap, or some other brand?
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Re: New User: L98 Engine Trouble (Midnight89)
My only concern is the Hypertech Power Coil. Mid-America claims that the coil requires a higher quality distributor cap and rotor to withstand the higher voltages. Will the Conrad suffice, or should I look into an Accel Hi-Performance Cap, or some other brand?